Lowest Cost Orbital Launcher discussion

[Kaputnik]

Following the discussion about a 'SCUD class' launcher (http://forum.nasaspaceflight.com/index.php?topic=30646.0) I thought I would see if anybody had any thoughts on what it would take to produce a lowest cost micro-launcher.

The SCUD discussion revolved around using a SCUD missile topped off with various combinations of existing or new upper stages. The trouble with these stages is that they are specifically designed for spaceflight and carry large costs.

What I would propose discussing is the use of primarily ordnance-based stages to create a comparatively low performance vehicle.

I would expect that multiple stages will be essential due to poor overall performance of each stage. However if the objective is just to put a micro-sat into a very low orbit, perhaps this is possible.

Thoughts, anyone?

[R7]

Charles Pooley has some interesting ideas about really small LVs and payloads.

http://microlaunchers.com/

Build one for under £1000 and win £9,999.99!

http://www.n-prize.com/

[Kaputnik]

Hadn't heard of the N-prize before. Good luck to them!

Manual flight control is an interesting idea (from Pooley's site). I was thinking more along the lines of a smartphone-based avionics package. Are the accelerometers/GPS in a smartphone capable of the required degree of accuracy?

The other thing I considered was a spin-stabilised upper stage, probably based on high-powered solids as used in model rocketry. The burden of very precise attitude control, as well as the roll control itself, would then be on a lower stage.

[Ed LeBouthillier]

Following the discussion about a 'SCUD class' launcher  I thought I would see if anybody had any thoughts on what it would take to produce a lowest cost micro-launcher.

Let's start by asking what you think a microlauncher would be capable of.

Some people talk about payloads as small as the N-prize ( between 9.99 and 19.99 grams) but they sometimes go up to something as large as a few cubesats.

What kind of payload? What kind of orbit?

[Ed LeBouthillier]

Manual flight control is an interesting idea (from Pooley's site). I was thinking more along the lines of a smartphone-based avionics package. Are the accelerometers/GPS in a smartphone capable of the required degree of accuracy?

Commercial GPS, because of US law, will not be sufficient for a launch vehicle. There is a legal requirement that GPS systems stop providing position data when certain limits of velocity and altitude are reached (1000 knots and 60,000 feet altitude as I understand it). Many companies make available a GPS system which exceeds these limits but you have to  pay extra and sign certain contracts for them. Therefore, something other than a commercial GPS will be required.

The accelerometers in commercial phones usually have a lower-limit on accuracy, specifically their drift, that may preclude them from being accurate enough. However, there may be techniques that allow them to be used successfully (i.e. averaging data from multiple units).

[Kaputnik]

Let's start by asking what you think a microlauncher would be capable of.

Some people talk about payloads as small as the N-prize ( between 9.99 and 19.99 grams) but they sometimes go up to something as large as a few cubesats.

What kind of payload? What kind of orbit?

Well, at the most basic, just the final stage of the vehicle, into an orbit capable of surviving for more than one revolution. But in order to verify that this had been achieved, I can see the value in an N-prize style transmitter to allow detection of the vehicle.

[Kaputnik]

Manual flight control is an interesting idea (from Pooley's site). I was thinking more along the lines of a smartphone-based avionics package. Are the accelerometers/GPS in a smartphone capable of the required degree of accuracy?

Commercial GPS, because of US law, will not be sufficient for a launch vehicle. There is a legal requirement that GPS systems stop providing position data when certain limits of velocity and altitude are reached (1000 knots and 60,000 feet altitude as I understand it). Many companies make available a GPS system which exceeds these limits but you have to  pay extra and sign certain contracts for them. Therefore, something other than a commercial GPS will be required.

The accelerometers in commercial phones usually have a lower-limit on accuracy, specifically their drift, that may preclude them from being accurate enough. However, there may be techniques that allow them to be used successfully (i.e. averaging data from multiple units).

That's really interesting- I did not know this. I would have thought that a suitably skilled person could 'hack' a GPS receiver to overcome these limits- unless a conventional receiver is technical incapable of processing the data when in this sort of range.

What sort of accuracy might be required during ascent? Obviously I understand that delta-v will be lost rapidly if the vehicle is not following a precise path... but perhaps a few degrees either way is acceptable, assuming sufficient margin?

[edkyle99]

Thoughts, anyone?

I would start by looking toward widely produced propulsion elements, like the solid motors used in U.S. naval missiles or sounding rockets.  Spin stabilization during some phases of flight, like sounding rockets, might offer a way to simplify flight control. 

But no matter what, the final stage or stages will have to have guidance and good mass ratios, so that's where the money will be needed.

 - Ed Kyle

[Ed LeBouthillier]

That's really interesting- I did not know this. I would have thought that a suitably skilled person could 'hack' a GPS receiver to overcome these limits- unless a conventional receiver is technical incapable of processing the data when in this sort of range.

It's a project in itself, though. It could take months to do that. Paul Breed [http://unreasonablerocket.blogspot.com/] has been working on his own GPS but I don't know what progress he has made.

What sort of accuracy might be required during ascent? Obviously I understand that delta-v will be lost rapidly if the vehicle is not following a precise path... but perhaps a few degrees either way is acceptable, assuming sufficient margin?

I don't know the answer to that question, precisely. I've started working on doing an analysis of the lower bound for accuracy in the guidance system, but I don't have an answer yet.

It's got to be pretty accurate. One thing to think about is getting a launch license. One of the things that the FAA will want to ensure is that you don't damage any other orbital assets (other satellites). Therefore, they'll want you to prove that your system has accurate-enough capability to attain a particular orbit that you won't endanger any other orbital assets.

So, I think that the answer is that the guidance system has to be accurate enough to get to the particular orbit you want. Typical commercial vehicles specify their orbits by specs such as:

For 310 nautical mile orbital altitude:
Perigee Altitude +/- 10km
Apogee Altitude +/- 80km
Inclination +/- 0.15 degrees

with a 3 sigma dispersion (this is from Pegasus XL)

If this is what other people are saying they're getting, you'll probably need to be able to say similar things about where your vehicle will be going. Otherwise, there is a possible debris problem that you'll have to prove you won't create.

So, if you have to say that your vehicle will always enter into the orbit insertion windows +/- 10 km [6.2 miles] that'll dictate some aspects of the required guidance system accuracy.

I don't think  you'll be able to get a launch license unless you can give these kinds of figures. You won't be able to get approval to launch unless you can say, with some degree of certainty, that you won't cause "damage to the uninvolved public" or their assets in orbit. The issue of orbital debris mitigation has become very serious.

So, I am of the school of thought that believes that accuracy in guidance is part of your debris mitigation strategy.

But, I could be wrong on this.

Cheers,
Ed L

[Ed LeBouthillier]

I would start by looking toward widely produced propulsion elements, like the solid motors used in U.S. naval missiles or sounding rockets.  Spin stabilization during some phases of flight, like sounding rockets, might offer a way to simplify flight control. 

But no matter what, the final stage or stages will have to have guidance and good mass ratios, so that's where the money will be needed.

Mr Kyle is correct that one good approach is to use already-developed propulsion elements. However, they bring with them two major problems that you'll have to overcome:

1. Cost - they're very expensive. Most already-available motors will cost several million each.

2. Payload Acceleration - most solids produce very high thrust so that small payloads will experience very high g's (on the order of 80 g's to 100 g's).

Since "Lowest Cost" is the goal, it may be necessary to explore other alternatives.

Otherwise, if "lowest cost" includes spending 1 or 2 million dollars each for the motors for a stage, then they'll be suitable.

Cheers,
Ed L

[R7]

The accelerometers in commercial phones usually have a lower-limit on accuracy, specifically their drift, that may preclude them from being accurate enough. However, there may be techniques that allow them to be used successfully (i.e. averaging data from multiple units).

That's really interesting- I did not know this. I would have thought that a suitably skilled person could 'hack' a GPS receiver to overcome these limits- unless a conventional receiver is technical incapable of processing the data when in this sort of range.

What sort of accuracy might be required during ascent? Obviously I understand that delta-v will be lost rapidly if the vehicle is not following a precise path... but perhaps a few degrees either way is acceptable, assuming sufficient margin?

I fear the limitation is built into the GPS chips so hard to hack, and if you'd pull it off MIBs come knocking on your door. Space launch business is very sensitive so best to keep everything clean and use common sense.

This leads to the accuracy question. With poor few degree accuracy you might be able to launch something to some orbit but that would probably seriously upset the big guys. Especially if ISS would theoretically be in the harm's way. IMO best to aim for necessary accuracy to guarantee that you hit apogee well below ISS and perigee minimum for stable orbit. 100nm or 200km circular would be really nice. edit3: Also to guarantee that you are low enough to decay quickly. Don't wanna leave space debris, again upsetting big boys.

You need sub-degree accuracy from INS during powered flight. Mobile phones aren't sufficient. In fact do they even have gyros? Accelometers measure acceleration, gyros rate of angular chance. Some units have magnetometers, dunno if their accuracy is enough for crude INS angle measurement, doubt it.  AFAIK the successful amateurs like Armadillo have used COTS INS units in the five digit price. Bad for N-Prize and if you are outside US then ITAR comes in play. Hmm did Paul Breed use RC helicopter gyros or something similar?

There are relatively accurate MEMS units, even with accelometers/gyros for all 6 degrees of freedom, but because they are mechanical you have issues with vibration and acceleration, they affect the readouts. Fiberoptic gyros are nice, resistant and stable. There's at least one russian manufacturer where you might get a unit for four digit figure, but you need three units for proper INS.

A propeller head idea that might have a fighting chance would be to use cheap MEMS unit to boost out of most of the atmosphere and then use startracker. Hook up couple cams on the nose, connect to your controller and start computing. Startracker is nice because error is constant, gyros integrate the angle so error grows with time.

Spin stabilization of upper stages would be so Juno-I, von Braun would be proud. But again you'd have the accuracy issue, Juno wasn't exactly stellar in insertion precision, but back then any orbit was OK

edit: also forget your multicore android phone for guidance computer. Even the most basic 8bit ~20Mhz microcontroller flies hypersonic loops around what guided men to the LEO and Moon in the 60s. Simpler chip, smaller chip, less chance for errors by space radiation. IIRC 8bit Atmel AVRs have worked well on cubesats. Just forget highlevel programming crap, java etc fluff. Go old school and do some assembly. At least I would.

edit2:

I don't know the answer to that question, precisely. I've started working on doing an analysis of the lower bound for accuracy in the guidance system, but I don't have an answer yet.

I can't say actual minimum accuracy either for crude LV but recall some Apollo-documents that stated gyros rated for 0.05 degree rift per hour. So that's a start. Relatively simple orbital math would yield actual answers, but at least I gotta open astrodynamics book again for that 

[Ed LeBouthillier]

Well, at the most basic, just the final stage of the vehicle, into an orbit capable of surviving for more than one revolution. But in order to verify that this had been achieved, I can see the value in an N-prize style transmitter to allow detection of the vehicle.

Alright then, let's look at the N-prize as an example: 20 grams [0.71 ounces] to a 185 km circular orbit from an inclination of 25 degrees North (in other words you have to launch from somewhere which is in the Continental US, particularly Florida somewhere).

Does that sound good?

Cheers,
Ed L

[Ed LeBouthillier]

Well, at the most basic, just the final stage of the vehicle, into an orbit capable of surviving for more than one revolution. But in order to verify that this had been achieved, I can see the value in an N-prize style transmitter to allow detection of the vehicle.

Oh, one other issue, do you want to consider any possible design (i.e. including balloon launch) or do you only want to consider approaches for which you are likely to get a launch license?

There are a number of people that suggest balloon launch, but I think that the FAA requirements will preclude their use because of the large potential for damage to the "uninvolved public."

Ed L

[R7]

There are a number of people that suggest balloon launch

'Good' way to complicate things. And increases requirement for INS accuracy, it would have to keep running also during balloon ascend. Don't see how you could reset it while rocket wobbles here and there hanging from the balloon.

[Ed LeBouthillier]

'Good' way to complicate things. And increases requirement for INS accuracy, it would have to keep running also during balloon ascend. Don't see how you could reset it while rocket wobbles here and there hanging from the balloon.

Yeah, high altitude launch does have its benefits. It might be worth considering an air launch from a small aircraft. But the idea that the FAA will let you let loose a balloon, with at least several hundred pounds of flammables with a potential to go very wrong, seems highly unlikely.

Cheers,
Ed L

[R7]

It might be worth considering an air launch from a small aircraft.

Well better than balloon (did any X-Prize teams that went for balloon approach manage even one test launch? IIRC no) but you'd have the same INS problem. I'm thinking some crude homemade INS here, cheap, barely enough required insertion accuracy for brief few minutes powered flight. The plane would have to carry another unit with much greater accuracy to hand over coordinates to the rocket when launching. Or you have to get better unit for the rocket.

[Ed LeBouthillier]

Alright then, let's look at the N-prize as an example: 20 grams [0.71 ounces] to a 185 km circular orbit from an inclination of 25 degrees North (in other words you have to launch from somewhere which is in the Continental US, particularly Florida somewhere).

Oh, one other thing. I've done some "messing around" with small launcher designs in the past. I have them online here:

http://home.earthlink.net/~apendragn/atg/qp/

You may find something interesting there. I would caution that I don't consider some of these designs very good, as I've learned much since I wrote them, but they're still good background material in there....

Cheers,
Ed L

[Kaputnik]

Thanks for the input guys, really interesting.
One thing that this has highlighted, for me, is that the best route probably depends on where you are located globally. A US citizen has access to different materials and tools, and is perhaps bound by different rules, than someone located in a different country.
Given that this grew out of the Scud discussion, I was originally thinking ordnance-based. I would guess that in the right place in the world, if you talked to the right people, you could probably get your hands on some pretty powerful hardware. But I suppose talk of costs becomes meaningless when it is no longer an open market.

The star-tracker upper stage is perhaps similar to Pooley's horizon idea. But I assume that this is incompatible with spin stabilisation.

[Ed LeBouthillier]

Thanks for the input guys, really interesting.
One thing that this has highlighted, for me, is that the best route probably depends on where you are located globally. A US citizen has access to different materials and tools, and is perhaps bound by different rules, than someone located in a different country.

Yeah, I think it is the Outer Space Treaty which imposes obligations on governments:

    Article VI of the Outer Space Treaty deals with international
    responsibility, stating that "the activities of non-governmental
    entities in outer space, including the Moon and other celestial
    bodies, shall require authorization and continuing supervision
    by the appropriate State Party to the Treaty" and that States
    Parties shall bear international responsibility for national space
    activities whether carried out by governmental or
    non-governmental entities.
    - Wikipedia [http://en.wikipedia.org/wiki/Outer_Space_Treaty]

So, this section obligates all signatory governments to the same thing, but each implements the regulations for its citizens differently.

Given that this grew out of the Scud discussion, I was originally thinking ordnance-based. I would guess that in the right place in the world, if you talked to the right people, you could probably get your hands on some pretty powerful hardware. But I suppose talk of costs becomes meaningless when it is no longer an open market.

The Iranian Safir launcher [http://en.wikipedia.org/wiki/Safir_rocket] is a perfect example of a two-stage vehicle based on ordinance technology like the Scud and other ballistic missiles. The first stage is essentially a scaled-up Scud (by 140%, I think) and the second stage is based on the R-27 MRBM.

The star-tracker upper stage is perhaps similar to Pooley's horizon idea. But I assume that this is incompatible with spin stabilisation.

Well, if you have spin stabilization, you don't need guidance. The whole point with spin stabilization is to have a lower stage (i.e. Stage 2 of a 3 stage vehicle) provide the guidance and control, spin up the third stage, point it and release it in the proper direction. Spin stabilization precludes the need for guidance in the final stage. At least that's my understanding of it.

I've written some articles on this idea here:

http://orbitalaspirations.blogspot.com/

Look at the earlier articles for reference.

Cheers,
Ed L

[R7]

The star-tracker upper stage is perhaps similar to Pooley's horizon idea. But I assume that this is incompatible with spin stabilisation.

Well, if you have spin stabilization, you don't need guidance. The whole point with spin stabilization is to have a lower stage (i.e. Stage 2 of a 3 stage vehicle) provide the guidance and control, spin up the third stage, point it and release it in the proper direction. Spin stabilization precludes the need for guidance in the final stage. At least that's my understanding of it.

Spot on. You can also spin up before launch like Juno-I. Ignition and separation of the spin-stabilized stage is of course critical.

Yes horizon tracking is related, maybe high res line scan cameras.

[Kaputnik]

I quite like the idea of a spin-stabilised final stage. It seems like it would allow it be extremely small and simple. If the 'payload' is just a few grammes, and able to withstand high g-forces, then a decent amount of delta-v could be achieved with a modestly sized solid motor.

I imagine that some middle stage would still be required to bridge the gap between the GPS cut-off and the final spun stage.

[R7]

I imagine that some middle stage would still be required to bridge the gap between the GPS cut-off and the final spun stage.

That, or the spun section can be multi-stage. Juno-I had three spun stages. The spinning cylinder contains two and the top spike is third. All stages made of multiples of same rocket motor, 11pcs, 3pcs and last one 1pc. edit: some clarity, plus note that the spun bundle just ejected spent motors, no additional spinning after separation from 1st guided stage. Simple brute force but worked to put Explorers in orbit.

See http://en.wikipedia.org/wiki/Jupiter-C

[Ed LeBouthillier]

I imagine that some middle stage would still be required to bridge the gap between the GPS cut-off and the final spun stage.

The problem is ... if you can afford a launcher ... then you can afford the GPS without CoCom limations  [http://en.wikipedia.org/wiki/CoCom]. However, there are other GPS-like systems as well, Glonass [http://en.wikipedia.org/wiki/Glonass], for example, which may not have the same limitations....the EU is also working on their own system, as I recall and the Chinese have their own system. See [http://en.wikipedia.org/wiki/Satellite_navigation_system]


Cheers,
Ed L

[Kaputnik]

Maybe that's the way to go, then. I'm surprised that the spin stabilisation was sufficient to maintain attitude over such a long time, and including staging events. Interesting stuff.

[Ed LeBouthillier]

What I would propose discussing is the use of primarily ordnance-based stages to create a comparatively low performance vehicle.

When you say "ordnance-based" stages, what particular kind of ordnance are you thinking about? Are you thinking existing military missiles such as surface-to-air missiles?

Would something like the SA-2 missile [http://en.wikipedia.org/wiki/S-75_Dvina] be the kind of vehicle you're talking about? I know that their motors are available on the open market now. They might make a good first stage motor for (relatively) cheap.

Cheers,
Ed L

[Solman]

 A strict interpretation of "lowest cost launcher" might include only the launch vehicle and not the entire system. In that case the lowest cost launcher could be a passive laser beam riding laser rocket.
 With the new 150KW Air Force laser for mounting on aircraft, a"Lightcraft" style launch vehicle heating air and then perhaps water carried aloft by the vehicle could perhaps be designed to passively ride the beam to orbit.
 Multiple lasers on multiple aircraft could perhaps work together to launch a small vehicle to orbit although this would likely require an active beam riding RCS increasing vehicle cost.
 This might be useful to provide a "quick look" from orbit anywhere in the world within a few minutes of a request. Since the lasers would still be used as a weapon system; the cost might be seen as little more than that required for the particular shot.

[Jim]

A strict interpretation of "lowest cost launcher" might include only the launch vehicle and not the entire system. In that case the lowest cost launcher could be a passive laser beam riding laser rocket.
 

no, it wouldn't.  It can't make into orbit alone, it needs an upperstage

[Robotbeat]

A strict interpretation of "lowest cost launcher" might include only the launch vehicle and not the entire system. In that case the lowest cost launcher could be a passive laser beam riding laser rocket.
 

no, it wouldn't.  It can't make into orbit alone, it needs an upperstage

BTW, there's a talk being given on this subject at my university on Thursday.

[Solman]

A strict interpretation of "lowest cost launcher" might include only the launch vehicle and not the entire system. In that case the lowest cost launcher could be a passive laser beam riding laser rocket.
 

no, it wouldn't.  It can't make into orbit alone, it needs an upperstage

 What Isp are you assuming? While I suppose you could design a laser rocket using air and water that would need a second stage but laser rockets can raise steam to a higher temp. than that of a H2-O2 chemical rocket in principle. This alone would insure SSTO but with air being used as propellant it seems well within the realm of possibility.
 Other propellant options exist as well such as ammonia and methane for even higher Isp.
 At any rate I'd love to see your assumptions and calculations.
 At any rate an upper stage would not raise cost of such a vehicle to a cost above that of the chemical options mentioned so far all of which require upper stages so your point is what exactly? The upper stage could also be a passive beam rider in principle couldn't it?

[RocketmanUS]

http://www.airlaunchllc.com/

What about the quick reach concept?

Multiple launch areas. The plan can be moved around so more customers than a fixed launch pad.

[Patchouli]

I fear the limitation is built into the GPS chips so hard to hack, and if you'd pull it off MIBs come knocking on your door. Space launch business is very sensitive so best to keep everything clean and use common sense.

GPS receivers are really nothing more then glorified radio receivers that receive position and time information from the satellites overhead.
The satellites broadcast their positions and the receiver computes it's position based on the delay of the signals.
It is entirely possible to implement your own GPS receiver with discrete devices and a FPGA.
There's nothing classified about the specification.

This would be devoid of speed and altitude the restrictions but mostly likely would be less accurate then an off the shelf unit.
It also would not be as compact.

Though it should be accurate enough enough to keep a rocket more or less on course enough to achieve orbit.
But your not going to do any rendezvous with it.
It might be less work to just get a space rated GPS as you're going to need clearance to launch anyway and reliability is an issue.
As for off the shelf gyro sensors though instead of cellphone units I'd use the ones used inside model aircraft and small civilian UAVs.
Even these probably would be more accurate then the mechanical gyros used on early launches.
If mass is not a problem the gyros in a recent aircraft auto pilot could be modified to work.

[Ed LeBouthillier]

A strict interpretation of "lowest cost launcher" might include only the launch vehicle and not the entire system. In that case the lowest cost launcher could be a passive laser beam riding laser rocket.

It should also be pointed out that laser propulsion is only theoretical at this time. The highest known altitude attained by laser propulsion is only hundreds of feet altitude (as I understand it). Therefore, there would be an extensive research cost to realize it to full practicality.

Therefore,

[R7]

A strict interpretation of "lowest cost launcher" might include only the launch vehicle and not the entire system.

Expensive self-delusion.

With the new 150KW Air Force laser for mounting on aircraft, a"Lightcraft" style launch vehicle heating air and then perhaps water carried aloft by the vehicle could perhaps be designed to passively ride the beam to orbit.

It's not passive because it needs to carry the propellant for exoatmospheric thrusting, and pump it to the reaction chamber (or whatever you call the section that does the heating using laser beam). AFAIK the studies so far have been spin stabilized test crafts going straight up (Lightcraft Technologies Inc). You'd need proper guidance to get into orbit.

Aircraft is expensive, powerful laser with pinpoint accuracy on an aircraft is expensive³. So much for low cost orbital launcher.

Multiple lasers on multiple aircraft could perhaps work together to launch a small vehicle to orbit although this would likely require an active beam riding RCS increasing vehicle cost.

expensive³ x multiple ...

[Jim]

 At any rate an upper stage would not raise cost of such a vehicle to a cost above that of the chemical options mentioned so far all of which require upper stages so your point is what exactly? The upper stage could also be a passive beam rider in principle couldn't it?

wrong on many counts.
The concept would require multiple lasers because a single one cannot maintain line of sight and the proper angles required.  That negates the principle of low cost, the laser stations have to be included.

Also, where are your calculations and assumptions for this unproven concept that makes it feasible much less viable?

[kevin-rf]

GPS receivers are really nothing more then glorified radio receivers that receive position and time information from the satellites overhead.
The satellites broadcast their positions and the receiver computes it's position based on the delay of the signals.
It is entirely possible to implement your own GPS receiver with discrete devices and a FPGA.
There's nothing classified about the specification.

This would be devoid of speed and altitude the restrictions but mostly likely would be less accurate then an off the shelf unit.
It also would not be as compact.

Years ago (early 90's) there was an excellent article in Circuit Cellars Ink on rolling your own GPS. I would use that a starting point. Though it's hard to argue with the single chip solutions available today.

Though I really question GPS accuracy being need for cheap low mass launchers. If away from populated areas (and populated overflight) gyro's and accelerometers are all you really need.

Though, my vision of this thread is taking the SS. Minnow out for a three hour tour, then lighting the candle very far from shore in a direction that doesn't overfly other stuff.

[edkyle99]

The star-tracker upper stage is perhaps similar to Pooley's horizon idea. But I assume that this is incompatible with spin stabilisation.

Poking around a bit, I've found mention of methods to detect star fields on a spinning spacecraft and use the resulting maps to determine orientation.  Horizon detection is easier, of course.

One additional thought:  perhaps this is where Gerald Bull and the likes of Project HARP fit - the idea of a Really Big Gun to serve, essentially, as a first stage.  Bull got something like a 100 kg projectile up to 180 km with a gun.  HARP fired around 1,000 projectiles up to 66 km.  All for a few million dollars.  And so on.

 - Ed Kyle

[Ed LeBouthillier]

Alright then, let's look at the N-prize as an example: 20 grams [0.71 ounces] to a 185 km circular orbit from an inclination of 25 degrees North (in other words you have to launch from somewhere which is in the Continental US, particularly Florida somewhere).

So, a 185 km circular orbit requires the following orbital velocity:

velocity = square_root( mu / r )

Where:

mu = the standard gravitational parameter [http://en.wikipedia.org/wiki/Standard_gravitational_parameter]

r = radius of orbit from center of Earth.

Using metric values:

velocity = square_root( 398,600.44189 / (6,378.1 km + 185 km)
velocity = square_root(398,600.44189 /  6563.1 km)
velocity = square_root( 60.73356 )
velocity = 7.79317 km/s [25568.14 feet per second]

An Eastward launch at the equator already provides about 0.463829 km/s [1521.358 fps].

The goal of the launch vehicle is to take the payload up to an altitude of 185 km [ 115 miles ] and ensure that it has a tangential velocity of 7.79317 km/s with negligible vertical velocity.

If it does this, it can be expected that the payload will stay in orbit for upwards of 200 hours or a little over a week [see Fundamentals of Astrodynamics, page 153 for orbital duration reference]. Of course, under some solar cycle conditions, it could be somewhat less or more.

[R7]

Though I really question GPS accuracy being need for cheap low mass launchers. If away from populated areas (and populated overflight) gyro's and accelerometers are all you really need.

You need gyros anyway, to keep the vehicle steady and have an idea for your orientation for roll control. Dunno if any real LV uses GPS for anything but nice-to-have backup to verify that INS has correct idea of your location. There have been papers about improving the accuracy of cheap MEMS gyro/accel system by mixing it's readouts with GPS using Kalman-filter. The math saturated my system

Poking around a bit, I've found mention of methods to detect star fields on a spinning spacecraft and use the resulting maps to determine orientation.  Horizon detection is easier, of course.

Horizon detection has it's quirks. To get accurate angles you need to look at several directions and do the trigonometry knowing your altitude. IR-detectors I suppose?

a gun.  HARP fired around 1,000 projectiles up to 66 km.  All for a few million dollars.  And so on.

Bad juju, but if you feel adventurous the gun is still there...

payload up to an altitude of 185 km [ 115 miles ]

If it does this, it can be expected that the payload will stay in orbit for upwards of 200 hours or a little over a week

The 185km originates from it being almost exactly 100 nautical miles. What did you use for ballistic coefficient for the 200hr estimate? Miniature things come down much faster than manned capsules etc.

[Ed LeBouthillier]

The 185km originates from it being almost exactly 100 nautical miles. What did you use for ballistic coefficient for the 200hr estimate? Miniature things come down much faster than manned capsules etc.

I used 185 km because it was what one of the posters had previously used as a goal orbit.

But, I didn't use a ballistic coefficient, I used the chart on page 153 of "Fundamentals of Astrodynamics," as I said in that post. It is a close-enough approximation. It gives an order-of-magnitude estimate of the duration of a flight. If you've got a better estimate then I welcome it. Besides, it's hard to get an estimate for something that hasn't even been designed yet.

You can find a PDF copy of that book floating around the internet, your local college library may have a copy or you can order it from Amazon for about $10. It's older but it's a pretty good book for general coverage of orbital dynamics theory.

[Ed LeBouthillier]

The 185km originates from it being almost exactly 100 nautical miles. What did you use for ballistic coefficient for the 200hr estimate? Miniature things come down much faster than manned capsules etc.

But, you're right. I checked the chart again and it is in nautical miles, not statute miles. The revised expected orbital duration based on that chart is about 50 hours, just over two days.

But, again, my whole point was not that it would be two days or one week. Many people that I talk to think that once something is in orbit that it's there for good. I was making the point that things in orbit decay and with an orbit of 185 km, one can expect things to decay pretty quickly (most especially for a small payload).

Cheers,
Ed L

[Solman]

A strict interpretation of "lowest cost launcher" might include only the launch vehicle and not the entire system. In that case the lowest cost launcher could be a passive laser beam riding laser rocket.

It should also be pointed out that laser propulsion is only theoretical at this time. The highest known altitude attained by laser propulsion is only hundreds of feet altitude (as I understand it). Therefore, there would be an extensive research cost to realize it to full practicality.

Therefore,

 The question posed in the OP was what the lowest cost launch vehicle would be, not what is the cheapest/fastest system to develop.
 That said, a laser rocket can be as simple as a teakettle and does not require pumps, etc. and if such a vehicle is designed as a passive beam rider it need have no moving parts at all. Passive beam riders were first patented for microwave propulsion in the late 50's. A laser rocket using this tech is itself about as simple in principle as could be. Laser rocket vehicles using active RCS could leverage the tech used to guide laser guided rockets and bombs almost directly.
 The example I'm sure you're referring to is the Myrabo "Lightcraft" test at AFRL which was conducted on a shoestring budget. I doubt the investment or time to develop this type of launch vehicle would be much but if you see a potential difficulty I'd love to hear about it.
 

[R7]

But, I didn't use a ballistic coefficient, I used the chart on page 153 of "Fundamentals of Astrodynamics," as I said in that post. It is a close-enough approximation. It gives an order-of-magnitude estimate of the duration of a flight. If you've got a better estimate then I welcome it. Besides, it's hard to get an estimate for something that hasn't even been designed yet.

You have to use ballistic coefficient to calculate drag effects. The FoA book chart assumed one for you, read last sentence on page 153. (emphasis mine, I have the book just didn't have it at hand earlier)

For circular orbits of a manned satellite about the size of the Gemini or Apollo spacecraft, Figure 3.1-1 shows the limits imposed by drag, radiation and meteorite damage considerations.

The rest of the book appears very light on drag effects. To calculate things accurately you need to know atmospheric model (densities at any altitude), spacecraft's reference area and drag coefficient. Add those to your flight model and integrate until you hit the point of reentry. Perpetual problem is that upper atmosphere properties fluctuate a lot.

Wiki has the basics, firearm enthusiasts are familiar with BC too.

http://en.wikipedia.org/wiki/Ballistic_coefficient

Some math

m = mass
A = reference area
C_d = drag coefficient
BC = ballistic coefficient

BC = m / (C_d * A)

Drag equation

rho = fluid density
v = velocity

F = 0.5 * rho * v² * C_d * A

Then apply the good old F = ma and BC to get deceleration due drag

a = 0.5 * rho * v² / BC

Higher BC -> lower deceleration and vice versa. This is why smaller objects decay faster.

[RanulfC]

Alright then, let's look at the N-prize as an example: 20 grams [0.71 ounces] to a 185 km circular orbit from an inclination of 25 degrees North (in other words you have to launch from somewhere which is in the Continental US, particularly Florida somewhere).

Oh, one other thing. I've done some "messing around" with small launcher designs in the past. I have them online here:

http://home.earthlink.net/~apendragn/atg/qp/

You may find something interesting there. I would caution that I don't consider some of these designs very good, as I've learned much since I wrote them, but they're still good background material in there....

Cheers,
Ed L

Ahh, that's why the name looked familar

Good stuff!

Randy

[Solman]

 At any rate an upper stage would not raise cost of such a vehicle to a cost above that of the chemical options mentioned so far all of which require upper stages so your point is what exactly? The upper stage could also be a passive beam rider in principle couldn't it?

wrong on many counts.
The concept would require multiple lasers because a single one cannot maintain line of sight and the proper angles required.  That negates the principle of low cost, the laser stations have to be included.

Also, where are your calculations and assumptions for this unproven concept that makes it feasible much less viable?

 Jim you asserted that a laser rocket cannot attain orbital velocity without being multi-stage. Extraordinary claim IMO requiring proof.
 As for multiple lasers being required - if true it would only mean more laser equipped planes at different locations - I would refer you to the "Parkin Launcher" as an example of beam propulsion that achieves orbit without multiple beam stations however. Anyway the vehicle geometry can allow for thrust to be on a different vector than the beam can't it?
 As for my assumptions being unproven there has been extensive work on beamed propulsion - google L. Myrabo.
 Also I referred to aircraft not ground based laser stations. If the Air Force deploys planes equipped with the new 150KW laser weapons they have already been developed and paid for and launching a nanosat would only involve costs associated with their use for that event.

[Ed LeBouthillier]

You have to use ballistic coefficient to calculate drag effects. The FoA book chart assumed one for you, read last sentence on page 153. (emphasis mine, I have the book just didn't have it at hand earlier)

No, I don't. If I don't care how long duration the orbit is beyond an order of magnitude. Several days to a week is all that I care about at this time. Later, I will do a longer duration examination.

I know that a 185 km orbit will be a short duration orbit (from a day to at most a week). I've seen that in other media as well.

To calculate things accurately you need to know atmospheric model (densities at any altitude), spacecraft's reference area and drag coefficient.

I don't want to calculate things accurately (yet). I don't care how long duration the orbit is right now. The specified goal was to put it in that orbit based on previous discussion. It's an input requirement; it's not subject to modification. That's the target orbit. To meet the goal of "being in orbit," it only has to last more than about 90 minutes (maybe about 3 hours at most).  We know that it will be short duration.

If you want to tell me how short of a duration, that'll be nice. If you say that a small payload at 185 km can't stay there for more than 3 hours, then the original requester can address that issue. Otherwise, it's not really important at this point.

[Ed LeBouthillier]

Ahh, that's why the name looked familar

Good stuff!

Cool, thanks. That stuff has its problems, but it's given me the opportunity to learn about this subject in greater detail.

I always welcome correction and guidance where I'm wrong.

Cheers,
Ed L

[RanulfC]

A "note" while I'm at it on "gun-launching" for small vehicles; A no longer availalbe website (haven't tried "wayback" yet so it might be there) was Glenn Olson's "alt.accel" site where he had a concept called "Amatuer Rocket Launch Assist" or ARLA. The idea was to "assist" an amatuer rocket launch with a ramjet stage. Many ways of getting up to ramjet speed were discussed (along with some good information on ramjet design itself) and the 'baseline' suggested method was using a high-pressure "air-cannon" design to deliver the initial "boost" to the vehicle.

He spec'ed out a bare-bones design for both a Mach-1 launch tube and a Mach-2 launch tube and while both were "do-able" for an amatuer group or solo effort the former of course was much easier (and cheaper) to construct than the latter.
(Though the latter actually had better performance modifiers overall)


Randy

[Solman]

A strict interpretation of "lowest cost launcher" might include only the launch vehicle and not the entire system.

Expensive self-delusion.

With the new 150KW Air Force laser for mounting on aircraft, a"Lightcraft" style launch vehicle heating air and then perhaps water carried aloft by the vehicle could perhaps be designed to passively ride the beam to orbit.

It's not passive because it needs to carry the propellant for exoatmospheric thrusting, and pump it to the reaction chamber (or whatever you call the section that does the heating using laser beam). AFAIK the studies so far have been spin stabilized test crafts going straight up (Lightcraft Technologies Inc). You'd need proper guidance to get into orbit.

Aircraft is expensive, powerful laser with pinpoint accuracy on an aircraft is expensive³. So much for low cost orbital launcher.

Multiple lasers on multiple aircraft could perhaps work together to launch a small vehicle to orbit although this would likely require an active beam riding RCS increasing vehicle cost.

expensive³ x multiple ...

 The Air Force may deploy laser equipped aircraft by 2015. If this happens these could in principle be used to launch nanosats couldn't they? If so then where is the expense and delusion?
 Also multiple planes could be used without increasing cost much since the planes are available and the lasers are capable of continuous operation and electrically powered. After a launch the lasers are still functional and have only used a small fraction of their operational lifetime.
 Beam riders arrange their geometry such that different segments of the beam power separate reaction chambers connected to nozzles angled such that if the rocket drifts off course thrust pushes it back to the center of the beam.
 While its true that active control (such as is required for every alternative launcher that has been mentioned on this thread) would increase cost, the basic tech has been developed for laser guided weaponry although RCS not fins would steer it.

[Ed LeBouthillier]

You have to use ballistic coefficient to calculate drag effects. The FoA book chart assumed one for you, read last sentence on page 153. (emphasis mine, I have the book just didn't have it at hand earlier)

If it helps you understand the approach that I'm taking, consider this a "spiral engineering" approach [http://en.wikipedia.org/wiki/Spiral_model]. I'm starting rough and working towards the details.

I know how to calculate drag and I understand the point you're making. However, if my memory serves properly, a 185 km orbit, while low, should be sufficient for one or two loops around the planet. That's all the level of accuracy that I care about at this time.

If you want to concentrate on the aerodynamic losses at orbit and the duration of orbit, feel free to post your results. I don't want to do that just yet.

[RanulfC]

Laser Launch comment hopefully before it gets ALL blown out of proportion

Solman; you want to read everything from Parkin, Kare, AND my Myrabo though you also need to keep in mind that the three authors each use a different "system" for propulsion. (Parkins is microwave, Kare is laser thermal, and Myrabo is laser thermal DETONATION)

Myrabo's "LightCraft" is a rather complex vehicle considering it has to have mirrored surfaces and complex focal planes. It also suffers from requireing the beam come from directly behind the vehicle and through the exhaust plume.
It's an "air-breather" for the most part but would require SOME on-board propellant for orbital insertion and an active control system to keep the vehicle centered in the beam. All models so far has been simple spin-stabilized with air pressure used to spin them up prior to launch.

Parkin's and Kare's "Heat-Exchanger" rockets on the other hand haven't actually been "test" flown at all though they should work quite well given enough laser power AND mulitple laser stations along the trajectory. Something you should note is that unlike the LightCraft they DO have on-board propellant (nominally Liquid Hydrogen has been suggested with "drop-tanks" carrying liquid Nitrogen for early boost) and are not designed for air-breathing flight.

Unlike the LightCraft, the HX rockets are designed so that one entire side is a "heat-exchanger" (for whatever beamed energy depending) which allows a greater capture area which can allow a wider beam spread somewhat. This avoids the need for a single, very high power pulsed beam such as is required by LightCraft and allows use of continous laser output systems such as diode lasers.

The "downside" is that this system still requires quite accurate beam pointing and usually multiple high-kilowatt lasers focused on the "target" to operate. The airborne lasers the USAF is currently talking about won't have the power or accuracy (and they would still have to be "ganged" to provide enough power which is difficult at best with multiple airborne aircraft) to perform as you're suggesting. In order to have the needed accuracy let alone power they would have to be "ground" based with dozens (at least) of lasers per site and at least three to four overlapping "sites" would be required for the system.

Payload is going to be limited even with a "full-up" system, (around 200kg maximum IIRC) and the laser system will be expensive to set up though maintenance and electical costs should make actual "operations" costs relativly cheap.

Unfortunatly it doesn't fit the OP's "requirements" at all.

Randy

[Kaputnik]

Interesting to see very different directions in this discussion.
Having started the thread, I realised quickly that the question is almost impossible to answer. I was starting from the assumption that some combination of high-power amateur rocket components, and reconfigured military hardware, coupled with consumer-grade electronics, would be the way to go. I am working on the assumption that, at least in certain parts of the world, it is probably possible for the right people to gain access to various types of ordnance at comparatively low prices- e.g. surplus or black-market. Of course, it would be almost impossible to put a price on this sort of equipment because of the nature of the marketplace. So perhaps it was a flawed assumption upon which to start the thread.

Having said that, Ed suggested earlier in the thread that SA-2 missile motors are widely and relatively cheaply available. Perhaps we could work forwards from that position and consider how these components could provide the starting point for an orbital vehicle? It would be helpful to get at least some idea of the likely costs involved.

[R7]

Perhaps we could work forwards from that position and consider how these components could provide the starting point for an orbital vehicle? It would be helpful to get at least some idea of the likely costs involved.

Yes it would help to know what toys to work with. And what payload range you had in mind?

Ed, I know you know the drag stuff, visited your pages, impressive stuff. Just thought it was in order to open up that stuff a bit more for others too. Size matters, a cube sat might stay up at 185km a day or so, N-Prize class 20 grams even less (unless it's a tungsten pellet ).

[Ed LeBouthillier]

Having said that, Ed suggested earlier in the thread that SA-2 missile motors are widely and relatively cheaply available. Perhaps we could work forwards from that position and consider how these components could provide the starting point for an orbital vehicle? It would be helpful to get at least some idea of the likely costs involved.

Well, the SA-2 missile motors have gone for about $12000 US on ebay. There is also a company in Eastern Europe that makes them commercially. So, they might be available for use in a small booster.

Knowing that price begins helping one understand possible costs for the first stage booster. If the motor is the most expensive single item, and most other parts add up to that cost, then you can see that a booster might *MIGHT* cost at a lower-bound estimate of about $25000. That's just for the first stage booster (of course there are a lot of 'if's in that chain of reasoning).

Otherwise, you're facing estimates produced by people like Armadillo Aerospace who say that they've spent about $2 million US on several Stig boosters (half of which they say is dedicated to labor costs) in the past 2 years. If they've produced about 4 or 5 vehicles, for $1 million, then you're talking about $250000 per stage.

So, we've got a broad price range with a lower estimate, using off-the-shelf ex-military hardware down towards $25,000 per booster, to a specialty-engineered vehicle costing about $250,000 per booster.

Now, some say you can go to smaller sizes and thereby reduce the costs below that. I am interested in exploring that idea, but I don't have any good estimates on that yet.

[Robotbeat]

Of course, a large portion of that cost is due to one-time engineering development. And just as much of the development (not per-unit) costs is developing a recovery method (which has saved a couple of their vehicles and allowed reflight in about half of their high-altitude launch attempts... though the recovery method is imperfect, to say the least... but they are definitely improving).

[Ed LeBouthillier]

Ed, I know you know the drag stuff, visited your pages, impressive stuff. Just thought it was in order to open up that stuff a bit more for others too. Size matters, a cube sat might stay up at 185km a day or so, N-Prize class 20 grams even less (unless it's a tungsten pellet ).

I know, you're right. Also, I apologize if I came off "testy."

I'm just hoping to cover some basic material before going into more detail. I want to post some links to online papers that others can review and learn from before we go around a little deeper.

I have found that there is a wide variety of knowledge levels on this subject and it helps to review some of the basics so that more people are up to speed before covering complications.

Seriously, my hope in having this discussion is that more people will know how to figure these things out for themselves. I've spent a few years researching and looking into small boosters and I think I've learned a few things that I think would be good if more people knew.

On the other hand, there's also a lot that I need to learn still....I really do welcome corrections. My apparent testyness wasn't that you were correcting me, but that we couldn't focus on more general issues before getting into "the problems...."

Cheers,
Ed L

[Ed LeBouthillier]

Of course, a large portion of that cost is due to one-time engineering development. And just as much of the development (not per-unit) costs is developing a recovery method (which has saved a couple of their vehicles and allowed reflight in about half of their high-altitude launch attempts... though the recovery method is imperfect, to say the least... but they are definitely improving).

That's absolutely true.

I have come to shy away from reusability because it does add complications to the overall task. But, maybe to get a launch license, you may have to have something to control the descent a bit. That may go away if you launch out at sea, though. I don't know.

Cheers,
Ed L

[Robotbeat]

Of course, a large portion of that cost is due to one-time engineering development. And just as much of the development (not per-unit) costs is developing a recovery method (which has saved a couple of their vehicles and allowed reflight in about half of their high-altitude launch attempts... though the recovery method is imperfect, to say the least... but they are definitely improving).

That's absolutely true.

I have come to shy away from reusability because it does add complications to the overall task. But, maybe to get a launch license, you may have to have something to control the descent a bit. That may go away if you launch out at sea, though. I don't know.

Cheers,
Ed L

If you want to actually get your payload back, you need to learn how to do some recovery anyway. That's partly the motivation for Masten and Armadillo pursuing reusability so aggressively, since that's their early source of funding. Additionally, you simply aren't going to open up space (significantly more than today) without reusability, as much as it has gotten a bad rap. Armadillo plans to use their current reusable Stig platform (actually, an extension of it) as eventually a pop-up stage, using an expendable upper stage or two for orbit. This is a good near-term compromise between reuse and expend.

Also, I suspect a lot of the benefit of expendable is a vestigial remnant of the huge amount of funding for expendables as munitions. For instance, without the industrial base and even surplus motors for solids from the national security need for ICBMs, I highly doubt solids would be nearly as competitive as Ed Kyle (and other intelligent folk) think they are. There's a reason why Russia has focused on liquid rockets, and it's not because they just adore wasting as much money as possible.

[R7]

I apologize if I came off "testy."

Nonsense, none required. Good discussion. The reason I wanted the payload BC known is because had to recently torpedo an "advanced concept" on the Advanced Concept area. The concept was to have ring of dust circling at very low LEO, 150km abouts, and then have a suborbital vehicle collide with it and have the ring push it into orbit. Otherwise good, but small dust decays immediately from that altitude. Just wanted to make sure that the goal here is within practicality. Here to share and learn more.

Also get your spiral/agile development model well, I have some IT background.

[Jim]

The Air Force may deploy laser equipped aircraft by 2015.

No, the ABL program was cancelled.  Also, it was only a 5 second burst and not continuous firing.

[Jim]

A strict interpretation of "lowest cost launcher" might include only the launch vehicle and not the entire system.

Expensive self-delusion.

With the new 150KW Air Force laser for mounting on aircraft, a"Lightcraft" style launch vehicle heating air and then perhaps water carried aloft by the vehicle could perhaps be designed to passively ride the beam to orbit.

It's not passive because it needs to carry the propellant for exoatmospheric thrusting, and pump it to the reaction chamber (or whatever you call the section that does the heating using laser beam). AFAIK the studies so far have been spin stabilized test crafts going straight up (Lightcraft Technologies Inc). You'd need proper guidance to get into orbit.

Aircraft is expensive, powerful laser with pinpoint accuracy on an aircraft is expensive³. So much for low cost orbital launcher.

Multiple lasers on multiple aircraft could perhaps work together to launch a small vehicle to orbit although this would likely require an active beam riding RCS increasing vehicle cost.

expensive³ x multiple ...

 The Air Force may deploy laser equipped aircraft by 2015. If this happens these could in principle be used to launch nanosats couldn't they? If so then where is the expense and delusion?
 

Self evident

[R7]

The Air Force may deploy laser equipped aircraft by 2015.

No, the ABL program was cancelled.  Also, it was only a 5 second burst and not continuous firing.

I think Solman means HELLADS. Not that it matters much...

http://www.airforce-technology.com/projects/high-energy-liquid-laser-programme/

[Robotbeat]

Chemical lasers are sort of a dead end, operationally. Very hazardous chemicals, expensive and corrosive, and logistically difficult. Much better to just focus on developing solid-state lasers of some sort so you just need electricity (or, equivalently, diesel or jet fuel... much easier logistically). Chemical lasers for launch are a non-starter.

[RocketmanUS]

1st stage an unmanned jet ( multiple engines ) to mach 2.0 to 2.5.
2nd stage main engine to LEO.
Two small OMS engine ( two for redundancy ) to circularize and or place 2nd stage in customers needed orbit ( place ).
Use OMS for reentry burn so could be reused.
2nd stage should be small enough for recovery with payload mass up to around 250 kg ).

This would be vertical take off.
1st stage to land horizontal like a regular jet.

[Kaputnik]

1st stage an unmanned jet ( multiple engines ) to mach 2.0 to 2.5.
2nd stage main engine to LEO.
Two small OMS engine ( two for redundancy ) to circularize and or place 2nd stage in customers needed orbit ( place ).
Use OMS for reentry burn so could be reused.
2nd stage should be small enough for recovery with payload mass up to around 250 kg ).

This would be vertical take off.
1st stage to land horizontal like a regular jet.

I reckon a $25,000 SA-2 based system might come in a little cheaper...

[RocketmanUS]

1st stage an unmanned jet ( multiple engines ) to mach 2.0 to 2.5.
2nd stage main engine to LEO.
Two small OMS engine ( two for redundancy ) to circularize and or place 2nd stage in customers needed orbit ( place ).
Use OMS for reentry burn so could be reused.
2nd stage should be small enough for recovery with payload mass up to around 250 kg ).

This would be vertical take off.
1st stage to land horizontal like a regular jet.

I reckon a $25,000 SA-2 based system might come in a little cheaper...

Link please to specs and prices.

[Kaputnik]

Just referring to Ed LeBouthillier's information on the previous page.

Ed- are you referring to the SA-2's liquid or solid motor component?

[Ed LeBouthillier]

Just referring to Ed LeBouthillier's information on the previous page.

Ed- are you referring to the SA-2's liquid or solid motor component?

Liquid motor. They were available a few months back. Actually, it went for $3500 on ebay:

http://www.ebay.com/itm/7700-lbf-thrust-rocket-engine-land-speed-vehicle-rocket-dragster-museum-/180994010029?item=180994010029&pt=Motors_Aviation_Parts_Gear&vxp=mtr&hash=item2a24156bad&nma=true&si=U5iKkm%252FqNMebgcW9EK2nLILUzaI%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

But, I know that there are other vendors that offer it around $12,000.

here are some pictures of it:

http://bangshift.com/blog/ebay-find-a-soviet-liquid-propellant-rocket-engine-that-would-be-fun-to-use-until-we-killed-ourselves-with-it.html

[Ed LeBouthillier]

Link please to specs and prices.

I just posted a link to the ebay sale. Here's a link to the commercial company:

http://www.edepro.com/ProductsLiquidPropellantTRM3500.html

They have highly detailed specs online for their version which are extremely similar to the original soviet missile....

Cheers,
Ed L

[Solman]

The Air Force may deploy laser equipped aircraft by 2015.

No, the ABL program was cancelled.  Also, it was only a 5 second burst and not continuous firing.

I am honestly surprised to see you unaware of the HELADS program.

[Solman]

A strict interpretation of "lowest cost launcher" might include only the launch vehicle and not the entire system.

Expensive self-delusion.

With the new 150KW Air Force laser for mounting on aircraft, a"Lightcraft" style launch vehicle heating air and then perhaps water carried aloft by the vehicle could perhaps be designed to passively ride the beam to orbit.

It's not passive because it needs to carry the propellant for exoatmospheric thrusting, and pump it to the reaction chamber (or whatever you call the section that does the heating using laser beam). AFAIK the studies so far have been spin stabilized test crafts going straight up (Lightcraft Technologies Inc). You'd need proper guidance to get into orbit.

Aircraft is expensive, powerful laser with pinpoint accuracy on an aircraft is expensive³. So much for low cost orbital launcher.

Multiple lasers on multiple aircraft could perhaps work together to launch a small vehicle to orbit although this would likely require an active beam riding RCS increasing vehicle cost.

expensive³ x multiple ...

 The Air Force may deploy laser equipped aircraft by 2015. If this happens these could in principle be used to launch nanosats couldn't they? If so then where is the expense and delusion?
 

Self evident

A rude, condescending and uninformed comment that is also wrong.
Also, an admission that your previous assertion that laser rockets require multiple stages to reach orbit was incorrect or a defense of your extraordinary assertion would be refreshing.

[Jim]

The Air Force may deploy laser equipped aircraft by 2015.

No, the ABL program was cancelled.  Also, it was only a 5 second burst and not continuous firing.

I am honestly surprised to see you unaware of the HELADS program.

No, HELADS is too low power and only short range.  And the USAF is no where close to deploying it in 2015.

[Jim]

Also, an admission that your previous assertion that laser rockets require multiple stages to reach orbit was incorrect or a defense of your extraordinary assertion would be refreshing.

No, I was correct.  They need a "stage" beyond the range of the lasers.   The concept of multiple lasers is absurd due to the logistics of basing the lasers.  Even more absurd than the ground based  missile defense laser concepts of the 80's.

[Solman]

Chemical lasers are sort of a dead end, operationally. Very hazardous chemicals, expensive and corrosive, and logistically difficult. Much better to just focus on developing solid-state lasers of some sort so you just need electricity (or, equivalently, diesel or jet fuel... much easier logistically). Chemical lasers for launch are a non-starter.

Google HELADS. Solid state 150KW liquid cooled electrically powered 5kg/KW laser weapons designed to be mounted on aircraft.

[Robotbeat]

Chemical lasers are sort of a dead end, operationally. Very hazardous chemicals, expensive and corrosive, and logistically difficult. Much better to just focus on developing solid-state lasers of some sort so you just need electricity (or, equivalently, diesel or jet fuel... much easier logistically). Chemical lasers for launch are a non-starter.

Google HELADS. Solid state 150KW liquid cooled electrically powered 5kg/KW laser weapons designed to be mounted on aircraft.

It's HELLADS, by the way. And yes, I knew about it.

[Solman]

Also, an admission that your previous assertion that laser rockets require multiple stages to reach orbit was incorrect or a defense of your extraordinary assertion would be refreshing.

No, I was correct.  They need a "stage" beyond the range of the lasers.

 HELLADS (thanks for the correction) operates at a power 150% of the 100KW ABM chemical laser and I have mentioned using multiple lasers so your point is what exactly?
 The LV in this case could have a very modest mass since the Isp can be high. A 10 lb. initial mass LV would be supplied with nearly 15 KW/lb. thrust and still accelerate by just one HELADS laser.
  As to the range required, acceleration can be high as well for such a craft if multiple lasers are used, so that range would be less of a problem. Lasers fired above most of the atmosphere by aircraft would have a very long range anyway wouldn't they?
 So no you are incorrect about the need for multiple stages because of range issues and as I previously pointed out multiple laser equipped aircraft could be spaced along the flight path anyway. A single stage could be used with multiple lasers so no need for multiple stages.
Also what is HELLADS's effective range? - I couldn't find that info and would appreciate the reference.
 If you were aware of it your previous comments are puzzling.
Jim you can just say you're wrong - its actually a sign of character and as Chris says "He who loves correction loves knowledge".
 I would add that basic politeness is a virtue.

[Solman]

The Air Force may deploy laser equipped aircraft by 2015.

No, the ABL program was cancelled.  Also, it was only a 5 second burst and not continuous firing.

I think Solman means HELLADS. Not that it matters much...

http://www.airforce-technology.com/projects/high-energy-liquid-laser-programme/

Thanks for pointing that out and yes I was referring to HELLADS.
The comment that it doesn't matter much seems a little harsh - do you think laser rockets will be developed? Do you think the concept of using HELLADS to accelerate small payloads to orbit is fatally flawed in some way?

[A_M_Swallow]

You only need flying lasers if the launch vehicles are going to many destinations.  A couple of destinations can be served by ground lasers at fixed locations.

[Robotbeat]

Also, an admission that your previous assertion that laser rockets require multiple stages to reach orbit was incorrect or a defense of your extraordinary assertion would be refreshing.

No, I was correct.  They need a "stage" beyond the range of the lasers.

 HELLADS (thanks for the correction) operates at a power 150% of the 100KW ABM chemical laser and I have mentioned using multiple lasers so your point is what exactly?
 The LV in this case could have a very modest mass since the Isp can be high. A 10 lb. initial mass LV would be supplied with nearly 15 KW/lb. thrust and still accelerate by just one HELADS laser.
  As to the range required, acceleration can be high as well for such a craft if multiple lasers are used, so that range would be less of a problem. Lasers fired above most of the atmosphere by aircraft would have a very long range anyway wouldn't they?
 So no you are incorrect about the need for multiple stages because of range issues and as I previously pointed out multiple laser equipped aircraft could be spaced along the flight path anyway. A single stage could be used with multiple lasers so no need for multiple stages.
Also what is HELLADS's effective range? - I couldn't find that info and would appreciate the reference.
 If you were aware of it your previous comments are puzzling.
Jim you can just say you're wrong - its actually a sign of character and as Chris says "He who loves correction loves knowledge".
 I would add that basic politeness is a virtue.

The ABL was in the Megawatt range, much more powerful than HELLADS.

[Ed LeBouthillier]

I reckon a $25,000 SA-2 based system might come in a little cheaper...

One other sample point is Paul Breed's statement that he could offer his vehicles for either $15,000 or $25,000 each (I'm sorry I forget the exact number). But, this does confirm that something of this scope could possibly meet this price range....

Cheers,
Ed L

[Ed LeBouthillier]

One other sample point is Paul Breed's statement that he could offer his vehicles for either $15,000 or $25,000 each (I'm sorry I forget the exact number). But, this does confirm that something of this scope could possibly meet this price range....

Here's Paul Breed's quote on prices for his vehicles:

    I had about 40 flights on the blue ball before it was destroyed.
    I could duplicate that vehicle for between 15 and 20K.
    I could duplicate a lower payload reusable lander using Fire
    Extinguisher tank age for ~5K

Just FYI

Ed L

[Robotbeat]

I want to see someone try a reusable, rail-launched, parachute and splashdown recovery, suborbital liquid rocket (doesn't have to get to the Karman line). It's within range of a concerted hobbyist effort (could be within FAA's amateur limit, which means less than 150km possible altitude and less than 200,000 lbf*s impulse). Doesn't even need active guidance. It'd let you focus almost entirely on recovery/reuse (in the supersonic regime). Bill on ARocket suggested it, and I think it's a great idea. EDIT:I reread what he wrote, and he didn't suggest my scheme, though he did inspire it by pointing out that most sounding rockets are rail-guided.... Japan's tiny orbital launch vehicle was rail-guided.

[RocketmanUS]

1st stage an unmanned jet ( multiple engines ) to mach 2.0 to 2.5.
2nd stage main engine to LEO.
Two small OMS engine ( two for redundancy ) to circularize and or place 2nd stage in customers needed orbit ( place ).
Use OMS for reentry burn so could be reused.
2nd stage should be small enough for recovery with payload mass up to around 250 kg ).

This would be vertical take off.
1st stage to land horizontal like a regular jet.

I reckon a $25,000 SA-2 based system might come in a little cheaper...

Using SA-2-
I don't think it would get much mass to orbit with it's low ISP ( ~221 ), at least not enough for a micro-sat.

Could cluster several around one. Center one stretched tank ( for added propellant to reach orbit after boosters separated ) and ground lit.

There was the concept of missiles fired from fighter planes to orbit to destroy satellites. Missiles would reach orbit but not orbital velocity as that was not needed.

http://en.wikipedia.org/wiki/Pegasus_%28rocket%29
Pegasus 443 kg to orbit with a good size fairing.
Cost estimates I've seen are around $30M.

A missiles I've seem prices around $1-2M.

What is the shelf life of the Rocket parts?
It might be cheaper to order a two staged launcher for air launch using the Merlin 1D and a small 2nd stage engine. That is if there were 100 orders over a ten year period ( at least 20 launches per year ). Would that not be safer than solids?

If the payloads are cheaper than the launcher then it could be cheaper to launch another if LOM.

For solids if they can load the propellant near the launch site for safety reduction of transport ( including mixing near site ). Plus low cost payloads and 20+ launches a year. Alaska or South Pacific launch. Also if the payload does not need to be placed in to tolerant of on orbit.

I think the key is many launches a year and using parts that are already in production. Except the tanks but made from the same materials as others in production.

[kevin-rf]

Just wondering, we recently had a Scud thread which needed a second stage, I wonder if the SA-2 motor could be used in a second stage?

Btw. Anyone have any scud cost estimates. Some quick google searches make me think scuds cost about $3 million. Just wondering when you start to get into the million ranges if cobbling together a bunch of solids would be a better approach.

[Ed LeBouthillier]

Using SA-2-
I don't think it would get much mass to orbit with it's low ISP ( ~221 ), at least not enough for a micro-sat.

That's not actually too bad of a sea level Isp for a booster.

With a Sea Level Isp of 221 s, I estimate the vacuum Isp at about 237 s.

Therefore, the average flight Isp will be about 233 seconds (just using a rule of thumb that I've found to be close enough).

It could be even better by welding on a bit of a nozzle extension.

With a thrust of about 7700 lbf, it'll work quite nicely for a small cubesat launcher, I think (although I'd have to do more analysis to be certain).

[Ed LeBouthillier]

Just wondering, we recently had a Scud thread which needed a second stage, I wonder if the SA-2 motor could be used in a second stage?

Btw. Anyone have any scud cost estimates. Some quick google searches make me think scuds cost about $3 million. Just wondering when you start to get into the million ranges if cobbling together a bunch of solids would be a better approach.

It probably has too much thrust and it works on poor propellants (not good enough Isp).

[Kaputnik]

Thanks for the links Ed. I hadn't realised that you were talking about the liquid engine on its own. But I suppose that does make sense since a fully loaded solid motor is not going to come up on eBay US...
Also, I had no idea that SAM engines would be as advanced as that- I would have assumed that they would be almost exclusively solid fuel, and that the few liquids would have been pressure-fed. I also did not expect to see a gimbal system.
The idea that you could get such an engine for $3,500 is amazing- hope whoever bought it doesn't blow themselves up...

[R7]

do you think laser rockets will be developed?

IMO unlikely to happen. Technical challenges are huge, and then you get geopolitical challenges. Laser strong and accurate enough to do the job would be an ASAT weapon whether you intended that or not.

LTI still has webpages but they've been very quiet. Shame, Tregenna Myrabo is hot 

Do you think the concept of using HELLADS to accelerate small payloads to orbit is fatally flawed in some way?

Yes. AFAIK it's kind of CIWS (see http://en.wikipedia.org/wiki/Close-in_weapon_system ) for future military aircrafts, shooting down incoming threats. Propelling a laser LV would require much greater range/accuracy.

On a general note I don't think laser propelled LV discussion belongs to this thread at all. AIUI the point of this thread was to try to create a concept of cheap LV using existing affordable engines/motors etc. Recommend you continue the laser propulsion discussion in dedicated thread (new or resurrect old, I'm sure it's been talked here many times).

[R7]

Also, I had no idea that SAM engines would be as advanced as that- I would have assumed that they would be almost exclusively solid fuel, and that the few liquids would have been pressure-fed. I also did not expect to see a gimbal system.

Actually the liquid design shows that the weapon system is not advanced, it's from 1957. The soviets used more complex liquid engines longer in military applications than the west (some still in use in Russia). Anything advanced by today's standards is solids because they make the perfect sense.

Are you sure it gimbaled in the original application? The SAM has large fins. I'd venture to guess the Serbian company may have added that later.

Ed, do you know what new TRM-3500 will cost? The ebay items looked as if stripped of any sensors, electronics. IRFNA as oxidizer, bit nasty. Maximum operation time 100 seconds, that's on the low side for booster.

[Ed LeBouthillier]

Ed, do you know what new TRM-3500 will cost? The ebay items looked as if stripped of any sensors, electronics. IRFNA as oxidizer, bit nasty.

No, I'm sorry I don't. But I do know that "used" motors pulled from missiles have been going for about 12K on ebay international (I think that the company is out of France). A brand-new motor will be substantially more, I would think.

Armadillo Aerospace said that they could offer their motor for about $50K US, just as a sample point. I think a brand-new SA2 motor would be about the same (at least).

Maximum operation time 100 seconds, that's on the low side for booster.

That's good enough. Especially for a small booster, it's main purpose is to get the upper stages out of the atmosphere. The Scud-based stage only burned for 68 seconds. Additionally, the max time may refer to the duration as designed for the missile, limited by the propellants.

Cheers,
Ed L

[Robotbeat]

Thanks for the links Ed. I hadn't realised that you were talking about the liquid engine on its own. But I suppose that does make sense since a fully loaded solid motor is not going to come up on eBay US...
Also, I had no idea that SAM engines would be as advanced as that- I would have assumed that they would be almost exclusively solid fuel, and that the few liquids would have been pressure-fed. I also did not expect to see a gimbal system.
The idea that you could get such an engine for $3,500 is amazing- hope whoever bought it doesn't blow themselves up...

V-2 was pump-fed, as are Scud.

[Robotbeat]

Except you want to test-fire it first. All modern engines for boosters can do much longer for test-fire purposes, etc. Ablative engines may be the exception.

[RanulfC]

The comment that it doesn't matter much seems a little harsh - do you think laser rockets will be developed? Do you think the concept of using HELLADS to accelerate small payloads to orbit is fatally flawed in some way?

Yes it is I'm afraid. You won't find an official "range" listed anywhere for HELLADS but it is explicit that it is for "surface-to-air" threats and the "danger" range for aircraft for such threats is UNDER 10,000ft. (Mostly "MANPADS" or short-range, passive guided missiles) Accuracy and power levels of the laser are going to limit actual enagement range to under a mile.

It doesn't actually say anywhere on the HELLADS site but the REAL "stopping-power" of the system is going to be in blinding IR seeking MANPADS rather than actually knocking out the projectile. Stopping artilliary and mortar rounds is going to take tracking and dwell time requirements up significantly over just flashing the IR seeker which is what the airborne HELLADS is going to do.

Laser propelled rockets MAY be developed at some point, but they are going to require sophisticated targeting and tracking services along with high power laser arrays that will NOT be airborne.

Randy

[Robotbeat]

...Do you think the concept of using HELLADS to accelerate small payloads to orbit is fatally flawed in some way?

Calculate the power needed to produce, say, 10kN of thrust (that's just one ton of force at lift-off... incredibly small) with, say, 1000s Isp (realistically, you won't get better than 600-800s because of losses).

Answer: about 50 Megawatts. That's about 300 times HELLADS. So yeah, I'd say that using HELLADS is pretty fatally flawed.

[RanulfC]

1st stage an unmanned jet ( multiple engines ) to mach 2.0 to 2.5.
2nd stage main engine to LEO.
Two small OMS engine ( two for redundancy ) to circularize and or place 2nd stage in customers needed orbit ( place ).
Use OMS for reentry burn so could be reused.
2nd stage should be small enough for recovery with payload mass up to around 250 kg ).

This would be vertical take off.
1st stage to land horizontal like a regular jet.

I reckon a $25,000 SA-2 based system might come in a little cheaper...

Maybe...

It really depends on the overall system if you're JUST going for low "intitial" cost then a one use SA-2 (or other expendable) based system probably would be the way to go. Doing it cheap but 'often' will probably take a different direction

I'll have to check further since I can't seem to find my ARLA file but I do believe that the calculated "cost" for a Mach-2 air-cannon launcher was around $30K dollars, so for a little over the cost of a single-use refurbished SA-2 motor "booster" you could start with a multiple use "booster" instead.

It really does depend on what you're "aiming" for... No pun intended, but there it is anyway

Randy

[Ed LeBouthillier]

It really depends on the overall system if you're JUST going for low "intitial" cost then a one use SA-2 (or other expendable) based system probably would be the way to go. Doing it cheap but 'often' will probably take a different direction

That's absolutely true. In one case you can build one and fly it and in the other, you have to begin considering an assembly line and logistics support and volume pricing on parts.

[Solman]

The comment that it doesn't matter much seems a little harsh - do you think laser rockets will be developed? Do you think the concept of using HELLADS to accelerate small payloads to orbit is fatally flawed in some way?

Yes it is I'm afraid. You won't find an official "range" listed anywhere for HELLADS but it is explicit that it is for "surface-to-air" threats and the "danger" range for aircraft for such threats is UNDER 10,000ft. (Mostly "MANPADS" or short-range, passive guided missiles) Accuracy and power levels of the laser are going to limit actual enagement range to under a mile.

It doesn't actually say anywhere on the HELLADS site but the REAL "stopping-power" of the system is going to be in blinding IR seeking MANPADS rather than actually knocking out the projectile. Stopping artilliary and mortar rounds is going to take tracking and dwell time requirements up significantly over just flashing the IR seeker which is what the airborne HELLADS is going to do.

Laser propelled rockets MAY be developed at some point, but they are going to require sophisticated targeting and tracking services along with high power laser arrays that will NOT be airborne.

Randy

 Thanks for the info.
Does it follow that it would have to be equipped with different optics if it were to have utility for launching then?
 Perhaps using this new liquid cooled laser could be adapted for the optics that were developed for the airborne ABM laser system? I believe that had the necessary range.
 Also I'm puzzled by your assertion that targeting would have to be developed as I believe it has been for the airborne laser ABM wasn't it?
 At any rate a passive beam rider would just follow the beam not the other way around. Also the kind of pinpoint targeting you mention is very similar to that used for laser guided rockets and bombs isn't it?
 Isn't your assertion that laser rockets will never use airborne lasers your opinion and not based on physics?
   

[Solman]

...Do you think the concept of using HELLADS to accelerate small payloads to orbit is fatally flawed in some way?

Calculate the power needed to produce, say, 10kN of thrust (that's just one ton of force at lift-off... incredibly small) with, say, 1000s Isp (realistically, you won't get better than 600-800s because of losses).

Answer: about 50 Megawatts. That's about 300 times HELLADS. So yeah, I'd say that using HELLADS is pretty fatally flawed.

 Why in the world would a laser rocket for launching a kilo or so to orbit need such a high power level? As I said, I'm talking about an initial mass of 10lb. or to be more accurate 5kg or so.

[Solman]

do you think laser rockets will be developed?

IMO unlikely to happen. Technical challenges are huge, and then you get geopolitical challenges. Laser strong and accurate enough to do the job would be an ASAT weapon whether you intended that or not.

LTI still has webpages but they've been very quiet. Shame, Tregenna Myrabo is hot 

Do you think the concept of using HELLADS to accelerate small payloads to orbit is fatally flawed in some way?

Yes. AFAIK it's kind of CIWS (see http://en.wikipedia.org/wiki/Close-in_weapon_system ) for future military aircrafts, shooting down incoming threats. Propelling a laser LV would require much greater range/accuracy.

On a general note I don't think laser propelled LV discussion belongs to this thread at all. AIUI the point of this thread was to try to create a concept of cheap LV using existing affordable engines/motors etc. Recommend you continue the laser propulsion discussion in dedicated thread (new or resurrect old, I'm sure it's been talked here many times).

 The OP said: "What I would propose discussing is the use of primarily ordnance-based stages to create a comparatively low performance vehicle."
 HELLADS could be considered "ordinance" couldn't it?
Of course its hardly "low performance"
 As for technical challenges, I just don't see that. A passive beam rider doesn't even have to have any moving parts or electronics.
 But thanks for the polite response and I'll take your advice on continuing discussion on this thread.

[Solman]

 One last thing - I want to acknowledge that Chris is of course correct about the airborne ABM laser being about a megawatt which is 6-7 times as powerful as HELLADS's laser and I had mistakenly said 100KW.
 Of course these new lasers could be ganged together to reach this power level and because they mass only 5kg/KW a wide variety of aircraft could loft such a system.

[RanulfC]

Thanks for the info.
Does it follow that it would have to be equipped with different optics if it were to have utility for launching then?

Seriously different optics would be needed.
Jodan Kare did a good study for NIAC that shows what's needed and you can read it here:
http://www.niac.usra.edu/files/studies/final_report/897Kare.pdf

The type and quality of optics you need are pretty much a large telescope.

Perhaps using this new liquid cooled laser could be adapted for the optics that were developed for the airborne ABM laser system? I believe that had the necessary range.

The ABL (Air-Borne-Laser, just FYI) used a large (the ball on the front) adaptive mirror system but at a MUCH greater power level and size. Such optics could and probably would be used for a laser launch system but they won't be "small" and there is the power issue. The new lasers would require multiple emmiters which simply could not be ganged together into a small enough space to fit the dozens needed in a single airframe. Again see the Kare report.

Also I'm puzzled by your assertion that targeting would have to be developed as I believe it has been for the airborne laser ABM wasn't it?

It was. It required a seperate aircraft (an AWACS) to track and report on the target as well as a pretty sophisticated optical tracking system mounted on the ABL aircraft itself. Again it's not something that is going to fit into a small aircraft frame.

At any rate a passive beam rider would just follow the beam not the other way around. Also the kind of pinpoint targeting you mention is very similar to that used for laser guided rockets and bombs isn't it?

Here's probably your biggest mis-conclusion; Of the laser launch concepts only two are anything close to the "beam-rider" you assume. The "original" laser launch system proposed to ablate a solid "propellant" attached to the base of a vehicle with high-powered, pulses of laser energy which would propell the vehicle to orbit. Each pulse would vaporize and expand the material from the propellant with the nano-second between pulses allowing the "target" area to clear before the next pulse arrived. LightCraft uses a similar concept but instead uses mirrored surfaces on the vehicle to focus the laser into heating and expanding air in a similar manner.

The difference is that the former actually is not effected as much by beam angle to the ablative propellant because all vaporization/expansion would occur at a 90-degree angle to the propellant/vehicle. In other words the "beam" could actually hit the propellant at a high angle and still propel the vehicle forward.

LightCraft requires the beam to be preciscly from behind or it doesn't work which highly limits the concept.

In both these concepts though the laser has to be BOTH very high powered AND rapidly pulsed for the concept to work. In most cases a "weapons" laser is NOT pulsed as this requires extra equipment and usually costs you power. The ABL and the HELLAD are both BEAM or continious lasers in that the laser is constant from start up to power off rather than fireing in descreet pulses.

The Kare laser launch (and similarly the Parkinson Microwave version) use the fact that continious lasers are cheaper and easier to make and use and then use a heat-exchanger to transfer the laser (micowave) energy into the propellant.

In this case the angle and 'pointing' of the laser beam become very accute issues with the need to ensure the maximum laser (microwave) energy possible falling on the heat-exchanger at all time. Tracking and pointing of the laser beam becomes very important and accuracy down to a very small scale is needed.

Guidance by reflected laser light is a different kettle of fish itself. In short the sensor detects the scattered laser light reflected from the target and the bomb/rocket describes a tight spiral around the point where the laser beam hits/reflects. Accuracy is no where near as tight as that which is required for launch purposes.

Isn't your assertion that laser rockets will never use airborne lasers your opinion and not based on physics?

Note that "I" didn't say "never" but said that laser launch would not use an airborne platform because of the number, power, and targeting/tracking systems needed

The problem is the scale. You COULD use a number of ABL aircraft for laser launch of small payloads. It would REQUIRE a "number" of them as well, probably about 5 of them, (6 would be better as a back up) which you will note is MUCH more powerful and capable than the HELLAD you were suggesting. In addition you would have to "launch" the vehicle to an where the ABL aircraft could "engage" it with it's laser. (Around 10,000ft) The ABL was designed to fire through relativly "clear" air at it's flight level and above it and not below it, nor at stationary targets. Once the vehicle got up there and was engaged by the first ABL it would have to be targeted by each in turn across thier range and the vehicle itself would have to have the capability of performing the orbital circularization burn.

So what the 'point' we are trying to make here is you're looking at several multi-million dollar per copy aircraft, (and their support aircraft and infrastructure) to try and launch a very small vehicle/payload into orbit misses the point of the original post. Yes laser launch is possible, but no it won't be "low-cost" in the sense meant in this thread.

Randy

[Robotbeat]

...Do you think the concept of using HELLADS to accelerate small payloads to orbit is fatally flawed in some way?

Calculate the power needed to produce, say, 10kN of thrust (that's just one ton of force at lift-off... incredibly small) with, say, 1000s Isp (realistically, you won't get better than 600-800s because of losses).

Answer: about 50 Megawatts. That's about 300 times HELLADS. So yeah, I'd say that using HELLADS is pretty fatally flawed.

 Why in the world would a laser rocket for launching a kilo or so to orbit need such a high power level? As I said, I'm talking about an initial mass of 10lb. or to be more accurate 5kg or so.

Sketch a picture of what the heck you're thinking about. By being vague and not stating exactly what you're talking about, not only is it trivial to misinterpret what you're talking about, but it's also unfalsifiable, which is even worse.

If you're talking about using a solar thermal rocket driven by a laser, you're still subject to all the other constraints of rocket flight plus more. If you're talking about using a laser to heat air, then you definitely need another rocket stage.

[Ed LeBouthillier]

Of course these new lasers could be ganged together to reach this power level and because they mass only 5kg/KW a wide variety of aircraft could loft such a system.

So can I get you to build one of these in the next year or two for under $50K?

You can't. These are fantasy systems. The *ONLY* technology we currently have to get to orbit is rockets.

Unless you can build one for under $50K (or even $100K, or $200K) within the next year or two, it's not relevant to the discussion here.

[Robotbeat]

Yeah, start another thread, Solman.

[Ed LeBouthillier]

Ed, do you know what new TRM-3500 will cost? The ebay items looked as if stripped of any sensors, electronics. IRFNA as oxidizer, bit nasty.

I'll start doing some figures for a small launcher using the TRM-3500 as the motor of a first stage (since we have a lot of technical specs on that). Although we don't currently have a quote for it, let's presume that we could get something like it as a military surplus SA2 missile motor.

I'll see if I can get a quote from the manufacturer; they might be interested that someone is considering using their product.

Cheers,
Ed L

[Robotbeat]

Edit your quotes.

[edkyle99]

I've looked at working backward from the smallest existing U.S. launchers (Pegasus and Minotaur 1). 

A three-stage ground launched Pegasus, essentially a "Taurus Lite" using Orion 50 and 38 inch diameter motors, would be able to boost about 250 kg to LEO, or 350 kg if a fourth stage like a Star 27H were added. 

Shrinking the rocket should cut costs, right?  Well, maybe, but in that spirit consider removing the Orion 50SXL first stage and flying just the Orion 50XL and Orion 38 stages, topped by a small third stage like Star 30 or even smaller.  This rocket, only weighing about 6 tonnes at liftoff, should theoretically be able to boost 100 kg to LEO.  There are problems, of course.  Orion 50XL is nominally an air-lit stage, g-forces would be high at the end of the third stage burn, and this would be a "stumpy" looking rocket, if that matters.

Another alternative would be to look at the "Orion 32" series motors in the ATK catalog.  These  motors, only 32 inches in diameter, were developed in 2006 for the projected Sea Launched Intermediate Range Ballistic Missile.  A three-stage rocket composed of Orion 32-7, 32-4 and 32-2 motors would be able to launch about 80 kg to LEO.  This rocket, using motors designed to be low-cost, would weigh about 8 tonnes at liftoff - about 60% as much as just one solid strap-on motor on a Delta 2 rocket.  It would stand less than 12 meters tall and would be 0.813 meters in diameter - still smaller than a Delta 2 GEM (see comparison image).  It would also produce some high-g loads, but that almost seems inevitable for such light payloads.

 - Ed Kyle

[RanulfC]

It really depends on the overall system if you're JUST going for low "intitial" cost then a one use SA-2 (or other expendable) based system probably would be the way to go. Doing it cheap but 'often' will probably take a different direction

That's absolutely true. In one case you can build one and fly it and in the other, you have to begin considering an assembly line and logistics support and volume pricing on parts.

Well, also someplace that will let you put in a 300-foot(+) long Mach-2 air-cannon with a lot of "empty" space down-range to the east

So...

Put aside the idea of a Trebuchet Launch Assist (TLA) or building a giant-composite-re-curve bow then I take it?

Randy

[Patchouli]

Going the other direction vs small with lots of stages what about going with a hydrogen lox booster that is single stage to orbit?

Maybe use a single J-2 engine or LCPE with an extendable nozzle like the RL-10B-2.

A similar concept that used a lower ISP pressure fed system.
http://en.wikipedia.org/wiki/Aquarius_%28rocket%29
The same concept with a turbo pump engine would have a much lower dry mass and much larger payload.
For orbit correction etc something really simple and cheap maybe a pressure fed hypergolic or hybrid stage.

This also could provide a good chunk of the delta V needed for orbital injection which would increase the payload.

[Ed LeBouthillier]

Going the other direction vs small with lots of stages what about going with a hydrogen lox booster that is single stage to orbit?

Yeah, there are a lot of approaches to this. To properly do this, I would say we would have to firm up our requirements and do a formal trade study and then select whichever best suits our needs. But that's a lot of work (some of which I've done in the past).

Maybe use a single J-2 engine or LCPE with an extendable nozzle like the RL-10B-2.

Do you have a quote on what an J-2, LCPE or RL-10B-2 might cost? I think they're fairly pricey.

A similar concept that used a lower ISP pressure fed system.

Yes, there's definitely a lot of benefit in that approach. On the other hand, looking at people like Armadillo and Unreasonable Rocket, we see that motor development is a job in and off itself. Sometimes they can take years to develop. At this point, I'm seeing how to minimize motor development (which I don't think is entirely possible, but which we should be able to minimize).

The same concept with a turbo pump engine would have a much lower dry mass and much larger payload.

Sure. I'm just thinking, at this point, that (conceptually) there are some off-the-shelf motors available from military surplus/decommissioning.

For orbit correction etc something really simple and cheap maybe a pressure fed hypergolic or hybrid stage.

Yeah, I definitely think that the upper stages can be pressure fed. I personally prefer something with a bit more oomph for upper stages than most hypergolics provide in a pressure-fed form. But, presuming one had access to and the money for nitrogen tetroxide + hydrazine it is pretty capable. But there are definite delivery and management problems with those.

On the other hand, something like hydrogen peroxide might be worth considering (say with Kerosene) for upper stages. Paul Breed has had pretty good success with using that and it is much more manageable than hydrazine and nitrogen tetroxide. He has even been able to 3D print the motors. So, access to the motors is quantifiable in terms of price.

[Kaputnik]

Certainly looks like there are multiple ways in which to skin this particular cat.
Obviously it's not my place to specify how people want to take this discussion, but I would suggest that we stick to the simplest of premises: what is the lowest cost method of putting an object in orbit. By definition, that object needs to be either large enough to be tracked, or contain a transmitter, otherwise it would be impossible to verify the achievement. An orbit is, by definition, a complete circumnavigation of the Earth. For simplicity, let's talk about a single shot attempt/vehicle.

In addition to the potential role of military surplus hardware, I'm curious about what role HPR motors could play in this, if any- presumably this information is freely available somewhere? Also, in some ways the building of a guidance system using consumer grade electronics is the most interesting part of the whole idea.

[Ed LeBouthillier]

Obviously it's not my place to specify how people want to take this discussion, but I would suggest that we stick to the simplest of premises: what is the lowest cost method of putting an object in orbit.

Actually, as far as I'm concerned, for the purposes of this discussion since you started it, you're the customer. You specify the requirements and I'll try to meet them.

Obviously, I have my own goals in this. I learn from and keep my skills up by trying to meet your goals.

By definition, that object needs to be either large enough to be tracked, or contain a transmitter, otherwise it would be impossible to verify the achievement. An orbit is, by definition, a complete circumnavigation of the Earth. For simplicity, let's talk about a single shot attempt/vehicle.

That sounds reasonable.

In addition to the potential role of military surplus hardware, I'm curious about what role HPR motors could play in this, if any- presumably this information is freely available somewhere?

I have actually looked at HPR motors quite a bit. For the most part, though, they're usually not good enough mass ratios. When they are good enough, their thrusts are usually so high that you need a payload able to survive greater than 80 g's. However, for this discussion, it is definitely worth considering unless you want to set an upper bound on what g's the payload has to endure.

Also, in some ways the building of a guidance system using consumer grade electronics is the most interesting part of the whole idea.

I'll try to develop a set of reasonable specifications on the guidance/control system using commercial grade components.

Cheers,
Ed L

[Patchouli]

Yeah, there are a lot of approaches to this. To properly do this, I would say we would have to firm up our requirements and do a formal trade study and then select whichever best suits our needs. But that's a lot of work (some of which I've done in the past).

I think the target payload should be Delta II class.

EELV class seems too big but Pegasus class seems too small.

The cost seems to scale non linearly a vehicle twice as big is not twice as expensive so just size things for the cheapest large cryogenic engine you can find.

Do you have a quote on what an J-2, LCPE or RL-10B-2 might cost? I think they're fairly pricey.

I heard the J-2X was about half the cost of a SSME which runs 41 million so LCPE should be cheaper.
The RS-25e though might be the same price as the J-2X making it almost cheap enough for a cheap rocket.

The main goal would be to beat Zenit in cost per kg.

[RanulfC]

Obviously it's not my place to specify how people want to take this discussion, but I would suggest that we stick to the simplest of premises: what is the lowest cost method of putting an object in orbit.

Actually, as far as I'm concerned, for the purposes of this discussion since you started it, you're the customer. You specify the requirements and I'll try to meet them.

IE: It's all your fault and we're blaming you

FYI: last quote I can find on an RL-10 was about six years ago at @$10-million each. For what it's worth...

And personally I'd like to see what we could come up with for a single CubeSat launcher either singly or repeatably...

Randy

[Robotbeat]

Obviously it's not my place to specify how people want to take this discussion, but I would suggest that we stick to the simplest of premises: what is the lowest cost method of putting an object in orbit.

Actually, as far as I'm concerned, for the purposes of this discussion since you started it, you're the customer. You specify the requirements and I'll try to meet them.

IE: It's all your fault and we're blaming you

FYI: last quote I can find on an RL-10 was about six years ago at @$10-million each. For what it's worth...

And personally I'd like to see what we could come up with for a single CubeSat launcher either singly or repeatably...

Randy

This is the sort of thing often talked about on ARocket and by folks like Paul Breed (of http://unreasonablerocket.blogspot.com ... look at the archives... he is the one who did the Blue Ball at the NGLLC VTVL contest)

[R7]

And personally I'd like to see what we could come up with for a single CubeSat launcher either singly or repeatably...

This. Ed just found a great baseline booster engine for mid-five digit cost, how about we forget J-2s and RL-10s from this thread 

[Ed LeBouthillier]

And personally I'd like to see what we could come up with for a single CubeSat launcher either singly or repeatably...

This. Ed just found a great baseline booster engine for mid-five digit cost, how about we forget J-2s and RL-10s from this thread 

For what it's worth, without intending to, this is pretty much what I've got so far. The reason is that the booster motor sort of sets the size for the booster, which then specs the upper stages it can carry.

Since the motor has a thrust about 7700 lbf, I like to have the booster weigh about half of the sea level thrust. Everything else kind of follows.
There are some difficulties with the 3rd stage. It's dimensionally small, but I'm still looking....

I'm still working out the weight details, though. I'll post something when I've got more realistic numbers....

Cheers,
Ed L

[RocketmanUS]

Certainly looks like there are multiple ways in which to skin this particular cat.
Obviously it's not my place to specify how people want to take this discussion, but I would suggest that we stick to the simplest of premises: what is the lowest cost method of putting an object in orbit. By definition, that object needs to be either large enough to be tracked, or contain a transmitter, otherwise it would be impossible to verify the achievement. An orbit is, by definition, a complete circumnavigation of the Earth. For simplicity, let's talk about a single shot attempt/vehicle.

In addition to the potential role of military surplus hardware, I'm curious about what role HPR motors could play in this, if any- presumably this information is freely available somewhere? Also, in some ways the building of a guidance system using consumer grade electronics is the most interesting part of the whole idea.

Surplus would run out, non sustainable.

If you want to go with solids then you need to be able to mix the ingredients on site and load them in their casings too.

Stick with a two stage, less LOM risks.

Need to launch when there will most likely be good weather based on history for the launch area.

Launch as many as possible within one to three week periods.

Use the cheaper heavier materials with higher thrust and more cheap propellant to keep cost down.

The diameter of the casings for this low mass to orbit launcher would fit on highway trucks for lower transport cost.

Launch pad(s) need to have quick turn around time ( hours, not days or weeks ).

Also have multiple mobile launchers to the pad for more than one launch per day.

All payloads need to be placed in their fairings ready to be attached to the launcher before the rest of the launcher is assembled.

The 1st , 2nd and fairing should be made to assemble and placed on the ML within hours.

So what solids offer cheap and easy to make?

For safety reasons for solids for example what would the ground blast area be for an Atlas V SRB be? ( radius )
So for safety the storage hangers and assemble buildings need to be able to handle such a blast that the surface surroundings would be safe.

Stages non reusable.

[Ed LeBouthillier]

Here's my first cycle of spiral development on a launcher using the SA-2/TRM-3500 motor. Since this motor is nitric acid/kerosene, I decided to make each stage use those propellants.

The hardest stage here currently is stage 2. My idea is that stage 3 contains the guidance and control (including attitude control) and that stage 2 is merely a booster. The weight budget is pretty tight on this stage.

On the other hand, the other stages are pretty straightforward with quite a bit of margin.

The diameter is 20" which is the same as Armadillo Aerospace's Stig B. The fineness ratio is about 20 to 1. There is no recovery system in this design.

If this design passes a first-pass design review by you guys, then we can delve into the details of each stage and begin cost estimation of each of them in greater detail.

I have to admit that I did this quickly (all today). I usually try to take more time and review everything myself over several days to a week. Because of that, it is highly likely I made at least one mistake. Hopefully it won't completely invalidate the design.

Cheers,
Ed L

[Robotbeat]

I'm not convinced sticking with just two stages is the minimum-cost solution. Two-stages works well at scale, but for the "lowest cost" orbital launcher, it's not going to work. Two-stage essentially guarantees the need for a pump, too.

[Patchouli]

What about cheating a little and making use of an aircraft as the first stage?
The ASM-135 ASAT could be modified to launch a cube sat.

[brtbrt]

What about cheating a little and making use of an aircraft as the first stage?
The ASM-135 ASAT could be modified to launch a cube sat.

I'm not sure it had the delta-v to go orbital. Wiki (http://en.wikipedia.org/wiki/ASM-135_ASAT) says 24,000 km/h =~ 7km/sec, a little short.

[Ed LeBouthillier]

I'm not convinced sticking with just two stages is the minimum-cost solution. Two-stages works well at scale, but for the "lowest cost" orbital launcher, it's not going to work. Two-stage essentially guarantees the need for a pump, too.

yeah, I looked at a 2 stager first but it requires either lower mass ratios, higher Isp or else the vehicle is too huge. Therefore, I went to 3 stages and it fit the intended 1st stage motor size.

[brtbrt]

I'm not convinced sticking with just two stages is the minimum-cost solution. Two-stages works well at scale, but for the "lowest cost" orbital launcher, it's not going to work. Two-stage essentially guarantees the need for a pump, too.

yeah, I looked at a 2 stager first but it requires either lower mass ratios, higher Isp or else the vehicle is too huge. Therefore, I went to 3 stages and it fit the intended 1st stage motor size.

Ed, would growing the first stage and increasing the number of engines on it make it easier? Go to 2 or 4?

[Ed LeBouthillier]

Ed, would growing the first stage and increasing the number of engines on it make it easier? Go to 2 or 4?

Well, the first stage is about max for 1 TRM-3500 (it can go just a bit heavier). If we have two engines, the cost of the stage will go up 50% (presuming everything else is the cost of one motor).

I didn't look at 4 stages, but the gain usually isn't worth the trouble. As RocketmanUS pointed out, there is an increased chance of Loss Of Mission (LOM) with more stages. The mass benefit from two stages to three is quite pronounced, the mass benefit from three to four is not all that significant. Beyond that, the mass benefits approach zero, especially when one considers increased complexity.

It might be worth considering going with two stages and using two TRM-3500's for the first stage. I'll look into that....it's hard to make a cost comparison without already having some basis for estimating the cost.

One place that is interesting is here:

http://rocketmoonlighting.blogspot.com/2012/04/3d-printed-rockets-cost-curve.html

This provides some kind of basis for estimating the cost of printed motor chambers....

Cheers,
Ed L

[Patchouli]

What about cheating a little and making use of an aircraft as the first stage?
The ASM-135 ASAT could be modified to launch a cube sat.

I'm not sure it had the delta-v to go orbital. Wiki (http://en.wikipedia.org/wiki/ASM-135_ASAT) says 24,000 km/h =~ 7km/sec, a little short.

Remember it was carrying an 80s era cryogenicly cooled infrared sensor.
Without that payload and some higher ISP solid propellants it might achieve orbit.
More info
http://www.astronautix.com/lvs/asat.htm

This is the best pic I could find but it shows the size of the seeker vehicle.

[RocketmanUS]

What about cheating a little and making use of an aircraft as the first stage?
The ASM-135 ASAT could be modified to launch a cube sat.

I'm not sure it had the delta-v to go orbital. Wiki (http://en.wikipedia.org/wiki/ASM-135_ASAT) says 24,000 km/h =~ 7km/sec, a little short.

Replace the 3rd stage payload  ( 30 lb ) with a 3rd stage propulsion stage might get up to 7 lb payload to orbit. ( ruffly estimated )

Could the jet handle a greater mass missile and still launch it or was that the maximum mass missile it could handle for this type of mission?

[Patchouli]

What about cheating a little and making use of an aircraft as the first stage?
The ASM-135 ASAT could be modified to launch a cube sat.

I'm not sure it had the delta-v to go orbital. Wiki (http://en.wikipedia.org/wiki/ASM-135_ASAT) says 24,000 km/h =~ 7km/sec, a little short.

Replace the 3rd stage payload  ( 30 lb ) with a 3rd stage propulsion stage might get up to 7 lb payload to orbit. ( ruffly estimated )

Could the jet handle a greater mass missile and still launch it or was that the maximum mass missile it could handle for this type of mission?

The F15 can carry up to 23600lbs but the limiting factor would be the center hard point which normally carries a 600 gallon drop tank.

[RocketmanUS]

What about cheating a little and making use of an aircraft as the first stage?
The ASM-135 ASAT could be modified to launch a cube sat.

I'm not sure it had the delta-v to go orbital. Wiki (http://en.wikipedia.org/wiki/ASM-135_ASAT) says 24,000 km/h =~ 7km/sec, a little short.

Replace the 3rd stage payload  ( 30 lb ) with a 3rd stage propulsion stage might get up to 7 lb payload to orbit. ( ruffly estimated )

Could the jet handle a greater mass missile and still launch it or was that the maximum mass missile it could handle for this type of mission?

The F15 can carry up to 23600lbs but the limiting factor would be the center hard point which normally carries a 600 gallon drop tank.

And the velocity and altitude with a given mass attached to the jet.
ASM-135 ASAT mass was 2,600lb.
So double or triple that mass could the jet be able to do the job?
I'm assuming the jet would be modified in that attachment area to be able to handle the added mass there.

[R7]

The F15 can carry up to 23600lbs but the limiting factor would be the center hard point which normally carries a 600 gallon drop tank.

The liming factor would be availability and cost of F-15 when trying to design lowest cost orbital launcher.

[Ed LeBouthillier]

Ed, would growing the first stage and increasing the number of engines on it make it easier? Go to 2 or 4?

One other point regarding going to 4 stages. As you add stages, each stage gets smaller. In the 3 stage vehicle, the third stage is almost about as small as normal construction techniques allow. If I actually optimized the stages for delta V, then the 3rd stage would become very difficult to build. If it were a 4 stage vehicle, it would probably be nearly impossible for "amateurs" to build. Likely, the cost for the stage would go up.

Cheers,
Ed L

[Ed LeBouthillier]

What about cheating a little and making use of an aircraft as the first stage?
The ASM-135 ASAT could be modified to launch a cube sat.

There are definitely a lot of advantages for air launching. The overall vehicle is a bit smaller and the "first" stage rocket (which is actually the second stage) can run at near-vacuum efficiency.

Of course, you don't need an F-15 to launch something like this, but it would still have to carry something weighing about 1500 lbs to high altitude.

For a "lowest cost" orbiter, you might be able to rent the vehicle. But I've always argued that you're going to need extra insurance because the person who owns the aircraft would be highly concerned about loss of the aircraft if you're carrying around lots of flammable rocket stages.

The reason that I didn't look at it (yet) is because we decided on the motor first. With that motor, there's hardly any reason to consider reducing the size of the first stage.....

[Robotbeat]

Ed, would growing the first stage and increasing the number of engines on it make it easier? Go to 2 or 4?

One other point regarding going to 4 stages. As you add stages, each stage gets smaller. In the 3 stage vehicle, the third stage is almost about as small as normal construction techniques allow. If I actually optimized the stages for delta V, then the 3rd stage would become very difficult to build. If it were a 4 stage vehicle, it would probably be nearly impossible for "amateurs" to build. Likely, the cost for the stage would go up.

Cheers,
Ed L

Amateurs aren't likely to get to orbit anyway. ATK has tiny, high mass fraction solid rocket motors:
Look at the STAR 4G, it weighs just a bit over 1kg loaded: http://www.ltas-vis.ulg.ac.be/cmsms/uploads/File/DataSheetSolidATK.pdf

[Ed LeBouthillier]

Amateurs aren't likely to get to orbit anyway.

What!!! Don't burst my bubble :-)

Seriously, I accept that. But it's something I want to consider anyway. Maybe we can lay the groundwork now for a future generation of amateurs.

Look at the STAR 4G, it weighs just a bit over 1kg loaded: http://www.ltas-vis.ulg.ac.be/cmsms/uploads/File/DataSheetSolidATK.pdf

Yeah, but people who deal with them say that they are VERY expensive. The impression I get is about a million a piece because they are "aerospace quality." But I haven't tried getting a quote myself.

My understanding is that they are far more expensive for that one stage than we want to consider for the whole vehicle.

Additionally, when I've done the math with their motors, the payload experiences g's higher than 80 (I may not have looked at that exact motor, but I've looked at a number of their motors.....

Cheers,
Ed L

[Lar]

The liming factor would be availability and cost of F-15 when trying to design lowest cost orbital launcher.

How much do they rent for?

Only a semi facetious comment, actually. Although in reality I don't think they are something you can pick up at your local Hertz counter.

[Robotbeat]

Mig jets might be more attainable and cheaper. There are some privately held ones, you may be able to rent it or something.

[R7]

Mig jets might be more attainable and cheaper. There are some privately held ones, you may be able to rent it or something.

Correct. US just sold Saudis 80+ F-15s for $~30B so those are pretty steep.

While back you could rent a back seat on Mig-25 Foxbat for about $20,000 and fly to ~90k ft and do mach 2+. Now they offer Mig-31.

http://www.incredible-adventures.com/edgeofspace.html

Those old Mig-25s might be 'cheap' grabs for buying, and they pack might performance. Interesting connection to F-15 which was developed to counter Mig-25.

[Lar]

Mig jets might be more attainable and cheaper. There are some privately held ones, you may be able to rent it or something.

Correct. US just sold Saudis 80+ F-15s for $~30B so those are pretty steep.

While back you could rent a back seat on Mig-25 Foxbat for about $20,000 and fly to ~90k ft and do mach 2+. Now they offer Mig-31.

http://www.incredible-adventures.com/edgeofspace.html

Those old Mig-25s might be 'cheap' grabs for buying, and they pack might performance. Interesting connection to F-15 which was developed to counter Mig-25.

Too bad Bob Lutz crashed his Mirage (that could be a faulty memory)  but maybe he'd let you use his L-39.. dunno how much the hardpoints could hold (if it even has any??? it's a trainer)

http://www.airportjournals.com/display.cfm?varid=0505007

or maybe talk to Don Kirlin? he has a MIG-29 or two apparently and does rent time on aircraft... But as of that article the MIG-29s are not flightworthy

http://www.wired.com/wired/archive/13.10/kirlin_pr.html

But ya, they'd want extra insurance.

[RocketmanUS]

Mig jets might be more attainable and cheaper. There are some privately held ones, you may be able to rent it or something.

The was one for sale on the pawn shop tv show ( Nevada pawn shop ).
Not much as it cost to keep it and has to be flown. I think it was about $5,000 per hour to fly. If it could do the job ( with some modifications to care the rocket ) then the price would not be bad.

[Ed LeBouthillier]

I tried to attach these files to an earlier message, but the forum software blocked them.

Here's a link to an OpenRocket [http://openrocket.sourceforge.net/] simulation and motor file of the first stage flight:

SIMUATION FILE
http://home.earthlink.net/~codemonky/data/lnchr_3stg_001/lnchr_3stg_001.ork

MOTOR FILE
http://home.earthlink.net/~codemonky/data/lnchr_3stg_001/lnchr_3stg_001.eng

Cheers,
Ed L

[Kaputnik]

Ed, would growing the first stage and increasing the number of engines on it make it easier? Go to 2 or 4?

One other point regarding going to 4 stages. As you add stages, each stage gets smaller. In the 3 stage vehicle, the third stage is almost about as small as normal construction techniques allow. If I actually optimized the stages for delta V, then the 3rd stage would become very difficult to build. If it were a 4 stage vehicle, it would probably be nearly impossible for "amateurs" to build. Likely, the cost for the stage would go up.

Cheers,
Ed L

That's an interesting point on the minimum size of a stage. What assumptions is this based on? Surely a spin-stabilised solid motor could be incredibly small and still be a viable stage?

[Ed LeBouthillier]

That's an interesting point on the minimum size of a stage. What assumptions is this based on? Surely a spin-stabilised solid motor could be incredibly small and still be a viable stage?

It's just called the "Minimum Gauge Problem." It will apply to small solids as well. The issue is just 2 things: 1) The availability of the materials at the guage/thickness you require 2) The techniques of constructing something from those materials.

Just think about it. If the math says that the optimal thickness of the pressurant tank is 0.005" thick, then how do you construct a tank (or pressure vessel) with material that thin. As your vehicle gets smaller, the math will call for increasingly thinner material in your pressure tanks or even combustion chambers. The math will essentially call for aluminum-foil thin material; it's quite difficult to weld something that small. Even brazing material that small is problematic and many construction materials add so much weight that they violate the optimal weight.

But, there are ways around these problems. Electroforming is one technique whereby you can produce very thin walled but functional pressure vessels.

Another aspect of this applies to electronics. Even assuming you can produce the pressure vessels with thin enough walls, then you have to fit all of your electronics into the vehicle stage. But, much of the off-the-shelf electronics isn't available in smaller sizes. The off-the-shelf AVR microcontroller, for example, has a minimum physical size that it is offered at. Often, that is already too large to meet the weight budget.

For example, in the Agena upper stage, the electronics and guidance section weighed 1.5% of the whole vehicle. Now, suppose we scale that down to a 4 lb vehicle, then the weight budget for electronics would be 0.06 lbs (27 grams, less than 1 ounce). That's not a lot of weight to put in a full guidance navigation and control system.

So, all of this is generally known as the "Minimum Gauge Problem."

[ChileVerde]

Correct. US just sold Saudis 80+ F-15s for $~30B so those are pretty steep.

This is totally OT, but I've been following JDAM costs for the past decade and have noticed that the US really soaks its buddies when it comes to Foreign Military Sales, to the tune of a factor of ~3 depending on circumstances.

Edit: Apparently the $30B deal included modernization of some 70 existing aircraft, so just dividing $30B by 80ish doesn't get at the unit cost to the Saudis of the 80+ new ones except as an upper bound.

[Ed LeBouthillier]

Here's my first cycle of spiral development on a launcher using the SA-2/TRM-3500 motor. Since this motor is nitric acid/kerosene, I decided to make each stage use those propellants.

OK, I started relooking at this design and I realized that I did something kind of crummy. I'm so used to doing pressure fed first stages that I forgot that I could seriously reduce the first stage Stage Mass Ratio (SMR) towards a much lower value.

Therefore, I'm doing another design iteration on this. It will likely either increase the payload significantly or else make stage 2 much easier to build.

[Ed LeBouthillier]

OK, I started relooking at this design and I realized that I did something kind of crummy. I'm so used to doing pressure fed first stages that I forgot that I could seriously reduce the first stage Stage Mass Ratio (SMR) towards a much lower value.

Here's the design using the TRM-3500 for the first stage motor and some as-yet unspecified upper stage motors. It's able to put a cubesat into a 185 km orbit. It is actually more capable, with more performance, and is likely also able to do polar orbits.

Because I readjusted the weights through the stages, it should be easier to build than the other one as well.

I had to expand the diameter of the payload shroud because stage 2 motor diameter was larger. Rather than go with higher chamber pressure, I just decided to increase the diameter.

I think that the weights are fairly realistic in that they would be buildable with standard technologies (i.e. welding) and use off-the-shelf pressurant tanks.

[Ed LeBouthillier]

Here's the weight breakdown that I used in this design.

                              LNCHR_3STG_002 Weight Breakdown

Stage 1
     Propellant Weight.......................................................2790.167 lbs
     Emtpy Weight.............................................................418.525 lbs
          Motor Weight (50:1 Estimate)....................151.740 lbs
          Pressurant System................................69.150 lbs
               4 X Luxfer T123C........63.6 lbs
               Helium...................5.55 lbs
          Fin Can.........................................54.104 lbs
               Fin Can Frustrum........23.064 lbs
               Fins....................31.04 lbs
          Propellant Tanks................................88.666 lbs
               Oxidizer Tank...........56.775 lbs
               Fuel Tank...............16.533 lbs
          Payload Shroud.................................143.952 lbs
               Nosecone................38.378 lbs
               26" Cylindrical bay.....76.062 lbs
               Frustrum................29.512 lbs
          Unallocated Weight..............................54.865 lbs

Stage 2
     Propellant Weight......................................................572.694 lbs
     Empty Weight............................................................97.358 lbs
          Motor Weight (80:1 Estimate)....................15.694 lbs
          Pressurant System...............................25.700 lbs
               5X Luxfer T71A..........21.500 lbs
               Helium...................4.200 lbs
          Propellant Tanks................................26.049 lbs
               Oxidizer Tank...........12.948 lbs
               Fuel Tank................3.770 lbs
          Unallocated Weight..............................29.915 lbs
Stage 3
     Propellant Weight.......................................................18.562 lbs
     Empty Weight.............................................................7.425 lbs
          Motor Weight (80:1 Estimate)....................1.204 lbs
          Pressurant System...............................1.786 lbs
               1X Luxfer P07B..........1.7 lbs
               Helium..................0.086 lbs
          Propellant Tanks................................1.166 lbs
               Oxidizer Tank...........0.450 lbs
               Fuel Tank...............0.131 lbs
          Unallocated Weight..............................3.270 lbs

[Bob Shaw]

Ed: Have you thought of adding a ring of small SRBs to the first stage? Cheap and cheery, but possibly having quite an impact on payload to orbit...

[Ed LeBouthillier]

Ed: Have you thought of adding a ring of small SRBs to the first stage? Cheap and cheery, but possibly having quite an impact on payload to orbit...

No, I haven't even begun to consider increasing the performance yet. I'm just trying to work out a basic design that is reasonable.

Cheers,
Ed L

[Robotbeat]

BTW, the Vanguard rocket is the smallest GLOW rocket to get anything to orbit, beating out Japan's Lambda 4S (most figures are wrong for L4S's GLOW, it's actually about 28000lb GLOW vs Vanguard's 22000lb GLOW).

Vanguard had 3 stages, first was kerolox, then hypergolic, then solid.

Lambda 4S had 5 solid stages (stage "0" were boosters, I count them as a stage).

Neither rockets were terribly successful, but we could likely do better nowadays if someone were very motivated and could afford a dozen development launches.

[Ed LeBouthillier]

BTW, the Vanguard rocket is the smallest GLOW rocket to get anything to orbit, beating out Japan's Lambda 4S (most figures are wrong for L4S's GLOW, it's actually about 28000lb GLOW vs Vanguard's 22000lb GLOW).

Actually, I have to admit that I made that statement first and it looks like I was wrong. We had a discussion here on NasaSpaceflight about it and I corrected my article.

http://orbitalaspirations.blogspot.com/2011/10/japanese-lambda-4s-launcher.html

The Lambda had a GLOW of 20721 lbs vs the Vanguard's 22796 lbs. So, the Lambda beats out the Vanguard in being the smallest by about 2000 lbs.

Sorry for the confusion I created. It was very difficult doing the research on something that was largely only documented in Japanese sources. the available English language sources were also difficult to interpret.

Ed L

[Robotbeat]

BTW, the Vanguard rocket is the smallest GLOW rocket to get anything to orbit, beating out Japan's Lambda 4S (most figures are wrong for L4S's GLOW, it's actually about 28000lb GLOW vs Vanguard's 22000lb GLOW).

Actually, I have to admit that I made that statement first and it looks like I was wrong. We had a discussion here on NasaSpaceflight about it and I corrected my article.

http://orbitalaspirations.blogspot.com/2011/10/japanese-lambda-4s-launcher.html

The Lambda had a GLOW of 20721 lbs vs the Vanguard's 22796 lbs. So, the Lambda beats out the Vanguard in being the smallest by about 2000 lbs.

Sorry for the confusion I created. It was very difficult doing the research on something that was largely only documented in Japanese sources. the available English language sources were also difficult to interpret.

Ed L

LOL, okay. You were the source, of course.

But even still the difference isn't that great. The Vanguard first stage is a pretty run of the mill affair, a pump-fed kerolox first stage (but with the turbine powered by peroxide decomp). But Vanguard had a full gimbaled engine first stage, not the thrust-vanes of Scud (or V2, for that matter).

If you run a gas-generator for the pump using the main propellants, that alone should grab you extra performance (no need for a separate peroxide tank and plumbing, plus higher Isp). Modern electronics are a lot better, cheaper, and lighter, so that'd help significantly. Perhaps to the point that two stages would be sufficient.

[Proponent]

Wasn't Lambda 4S's payload quite a bit larger than Vanguard's?  Encyclopedia Astronautica quotes about 60 lb to LEO vs. 20.  For that matter, what about Black Arrow?  Again per Encyclopedia Astronautica, it's GLOW was about twice Lambda 4S's, but its payload was about three times.  Payload fractions for Vanguard, Lambda 4S and Black Arrow were about 0.1%, 0.2% and 0.3%, respectively.  If scaled down, Black Arrow would no doubt become less efficient, but it might still give a lighter design than Lambda 4S, especially if we're talking about dry mass, which probably matter more than gross mass.

[Robotbeat]

They were comparable. Vanguard got at least a 22kg satellite into orbit.

And definitely when you scale down you have a non-linear relationship between GLOW and payload. The smallest rockets will have the worst ratio. But, if a modern version were developed, modern manufacturing techniques and miniaturization of avionics (MEMS gyros, GPS, etc) and modern alloys and/or composites should be able to improve things markedly. Pump-fed stages one and two should be able to do very well.

[Ed LeBouthillier]

Wasn't Lambda 4S's payload quite a bit larger than Vanguard's?  Encyclopedia Astronautica quotes about 60 lb to LEO vs. 20.

My understanding is that the payload of Lambda consisted of the empty stage 4 plus its actual payload. They were combined, not separated, as is normally done. [http://en.wikipedia.org/wiki/%C5%8Csumi_(satellite)]

If you consider the same thing for Vanguard, then Vanguard's payload to orbit was about 22 lbs plus the empty stage 3 which was 48.27 lbs for a total of about 70 lbs.

Ed L

[savuporo]

We have it on a good authority that one can't really do an orbital launcher with under $10M in development funding. That has to be amortized over a realistic number of launches.
Going rate for a cubesat launch is about $100K apparently. So, assuming your hardware, operations, range and insurance cost exactly nothing it will take 100 launches with paying customers to even come close to breaking even.
What i'm wondering is if the actual hardware cost, at least for an expendable system, would even play a first order role in closing the business case for a nanosat launcher.

[Robotbeat]

We have it on a good authority that one can't really do an orbital launcher with under $10M in development funding. That has to be amortized over a realistic number of launches.
Going rate for a cubesat launch is about $100K apparently. So, assuming your hardware, operations, range and insurance cost exactly nothing it will take 100 launches with paying customers to even come close to breaking even.
What i'm wondering is if the actual hardware cost, at least for an expendable system, would even play a first order role in closing the business case for a nanosat launcher.

Just so We're clear, he thinks there's no way to do it for less than a million. He says that less than $10M is very very difficult.

Your best bet is probably to rely most on existing solids of some sort.

[R7]

What would be expected range costs for nanosat launcher? Where would potential launch sites be?

The more remote the better, to a point, I guess. Could the costs be reduced to pretty much filing a NOTAM? Andøya in Norway comes to mind, might be a good place to do SSO/polar launches towards north without much risk/disturbance to anybody.

[Ed LeBouthillier]

We have it on a good authority that one can't really do an orbital launcher with under $10M in development funding.

I've never been good at listening to authority. I think we should prove them wrong. :-)

In fact, I already asked that authority, personally, and he has said that there are cheaper approaches than the way that they did it.

What i'm wondering is if the actual hardware cost, at least for an expendable system, would even play a first order role in closing the business case for a nanosat launcher.

Sure, that's a good question. I'm starting to work some of that out. I'm trying to get some of that posted here.

Anyway, even if it's true that "amateurs" will never do that, I would ask "what _CAN_ we do?"

Cheers,
Ed L

[Ed LeBouthillier]

What would be expected range costs for nanosat launcher? Where would potential launch sites be?

I don't think that there would be range costs. I do think that there will be insurance and it will be at least $25,000. That's based on reported values by Armadillo and Unreasonable.

The more remote the better, to a point, I guess. Could the costs be reduced to pretty much filing a NOTAM? Andøya in Norway comes to mind, might be a good place to do SSO/polar launches towards north without much risk/disturbance to anybody.

Sure, I don't think that one should use a formal range. A sea launch or launch from a place that places the flight almost entirely over the sea for the first stage or two would reduce the cost.

Additionally, a smaller vehicle will cost less, overall....

That's what I'm thinking....

Cheers,
Ed L

[Ed LeBouthillier]

OK, I've been delving into the details of stage 3.

Here's an image of the details a bit.

So far, the weight budget is looking good. After reaction control thrusters, it's looking like there is about 3 pounds for electronics (GNC, comms), pyro valve, one-way valves, regulator and batteries.

The reaction control thrusters I baselined are Moog 58-118. I'm not pretending we could afford to purchase these, but we might be able to duplicate them or find something similar cheaper. But as a proof-of-concept, the weights are realistic (based on off-the-shelf parts).

Cheers,
Ed L

[Ed LeBouthillier]

OK, I've been delving into the details of stage 3.

Doing a quick FMEA [http://en.wikipedia.org/wiki/FMEA] on the plumbing system, I thought that there were a few places that might be dangerous or mission ending events. Therefore, I've redesigned the plumbing a bit by adding a relief valve for overpressurization (failure or leakage of the regulator) as well as replaced the burst valves with pyro valves.

I think this would be a far safer design and one which would more likely fulfill the mission without too much weight penalty.

[Ed LeBouthillier]

So anyway, because we spec'd the TRM-3500 for the motor, this "microlauncher" is actually quite large. The first stage is, basically, as large as Stig B. The upper stages are quite large.

I have to admit, I'm pretty happy with the development of the 3rd stage. This has been one of the most reasonable approaches to the design of a 3rd stage, perhaps being the easiest third stage to build.

But, this was a worthy experiment to consider the use of this motor in cost reduction. We could begin to estimate costs from at the current level of detail, but I think that the original intent is to go smaller.

Is that correct, Mr. Kaputnik?

Do you want to consider a smaller launcher? What direction do you want to go? I think we should consider a smaller launcher before we start breaking things down for cost estimation.

[Robotbeat]

Helium tank should be carbon-fiber-overwrapped (makes it significantly lighter) and more round-ish. This is basically what everyone does, including amateur folk. It's not an expensive technology (amateur rocketeers sometimes use the carbon fiber tanks from paintball guns). Or, if you want to stick with metal, you can stick it in the liquid oxygen tank to reduce its mass. I don't know if you have a heat-exchanger system for the helium pressurant, but that would also reduce its mass significantly. As you diagram is right now, the helium tank looks to be quite massive.

[Ed LeBouthillier]

Helium tank should be carbon-fiber-overwrapped (makes it significantly lighter) and more round-ish. This is basically what everyone does, including amateur folk.

Sure, but I just used specs for off-the-shelf pressurant tanks. They are all stock Luxfer models. That makes it easy to estimate a price and availability. Higher performance is likely possible if it is custom-made. But, a "lowest cost" approach might suggest using off-the-shelf tank technology.

It's not an expensive technology (amateur rocketeers sometimes use the carbon fiber tanks from paintball guns). Or, if you want to stick with metal, you can stick it in the liquid oxygen tank to reduce its mass. I don't know if you have a heat-exchanger system for the helium pressurant, but that would also reduce its mass significantly. As you diagram is right now, the helium tank looks to be quite massive.

I don't explicitly have a heat exchanger in the design. I overcompensated and doubled the amount of pressurant. I think a heat exchanger would be a good idea. My thinking is that it could be added to the combustion chamber to extract some heat from there if needed. I didn't do a full thermodynamic joule-thomson effect analysis, but I kind of went with rule-of-thumb intuition based on previous analysis.

Yes, there is room for improvement in the pressurant system, though.

That's why I think this is a "pretty good" approximation of a design. There's room for improvement and there's margin for error.

Anyway, like I said, I would like to dive down in size to see what can be done with a smaller design. This first approach (perhaps actually the second iteration) was meant to establish a level of feasibility. Everyone can imagine the complexity and feasibility of a Stig-B first stage. We've even got some approximate quotes on their cost. I've tried to demonstrate the feasibility and complexity of the upper stages separately.

If we head down in size, things will get more difficult in some ways. I want to establish a level of feasibility and understanding so that we can begin to consider more difficult approaches as we scale down....

Cheers,
Ed L

[Ed LeBouthillier]

Helium tank should be carbon-fiber-overwrapped (makes it significantly lighter) and more round-ish. This is basically what everyone does, including amateur folk.

Also, one thing I should point out. The attitude control jets use the same helium supply as the propellant feed system. Therefore, more gas is needed. I'd rather reduce a bit of weight by putting that gas in a tank I need to have anyway. Otherwise, I'd need a separate tank, separate opening valve, separate regulator, presssure relief valve etc....

Again, I admit that I did not do a full analysis. There is room for improvement/optimization. But, remember, premature optimization is the root of all evil. At this point, the design is good enough and illustrates some particular points.

Ed L

[Ed LeBouthillier]

Here are some interesting papers related to scaling down launch vehicles:

1. How Small Can a Launch Vehicle Be?
John C Whitehead
[https://e-reports-ext.llnl.gov/pdf/321763.pdf]

2. A systems study of very small launch vehicles
Richard J. Francis Jr.
[http://dspace.mit.edu/handle/1721.1/9383]

3. A systems study of propulsion technologies for orbit and attitude control of microspacecraft
Adam P London
[http://dspace.mit.edu/handle/1721.1/10989]

4. Feasibility Study of European Launch System Dedicated to Micro Satellites
Paolo Baiocco and Amaya Espinosa
[http://articles.adsabs.harvard.edu/full/2004ESASP.571E..24B]

[Kaputnik]

But, this was a worthy experiment to consider the use of this motor in cost reduction. We could begin to estimate costs from at the current level of detail, but I think that the original intent is to go smaller.

Is that correct, Mr. Kaputnik?

Do you want to consider a smaller launcher? What direction do you want to go? I think we should consider a smaller launcher before we start breaking things down for cost estimation.

Apologies for being absent from the thread for a while- rather busy at work.

The intent wasn't really 'smaller' per se. Literally, I was asking, very simplistically, what would be the lowest cost route for getting something to orbit the Earth. Payload was implied only by virtue of the need to verify the achievement.

Just to respond to a question mooted up-thread: it was suggested that some form of cheap solid could be used for thrust at launch; Ed said that this sounded like an unnecessary upgrade. I would just like to explore the point by suggesting that a ring of solids used at launch could presumably allow a larger core stage.

Essentially, what I would propose is to take a ring of simple non-TVC solids, providing a good balance of impulse/$, with the core providing TVC, and sized so that upon SRM burnout the core velocity and T:W are adequate. The idea is to gain the maximum utility from a relatively small/cheap gimballed liquid engine, perhaps even allowing the vehicle to have only a single upper stage.
Of course, everything depends on what the cost of the solids would be.

[drbobguy]

I think the lowest-cost option would be a very small UAV, like the size of your fist.  It would have a tough center with magnets and/or some kind of thermite to bond to objects.  Then on the outside it would have helicopter blades.  Hide it near a launch pad somewhere in an inactive mode and then on the day of a launch activate it remotely and steer it to latch onto the upper stage of whichever launch vehicle you are going to piggyback on.

Parasitic launching!

[Ed LeBouthillier]

Apologies for being absent from the thread for a while- rather busy at work.

No biggie, we all have lives away from here (I hope).

Essentially, what I would propose is to take a ring of simple non-TVC solids, providing a good balance of impulse/$, with the core providing TVC, and sized so that upon SRM burnout the core velocity and T:W are adequate. The idea is to gain the maximum utility from a relatively small/cheap gimballed liquid engine, perhaps even allowing the vehicle to have only a single upper stage.
Of course, everything depends on what the cost of the solids would be.

So a single core stage which goes all the way to orbit, but which is lifted to where it can work by a ring of solids? Kind of like an R-7 [http://en.wikipedia.org/wiki/R-7_Semyorka]. Do you want two or more separate "stages" with the solids? For example, some delta launch vehicles with strap-ons lose them in stages.

I would point out, generally, that we haven't established any means of doing cost estimates so we have no basis for determining what is or isn't a "lowest cost orbital launcher."

[edkyle99]

Another alternative would be to look at the "Orion 32" series motors in the ATK catalog.  These  motors, only 32 inches in diameter, were developed in 2006 for the projected Sea Launched Intermediate Range Ballistic Missile.  A three-stage rocket composed of Orion 32-7, 32-4 and 32-2 motors would be able to launch about 80 kg to LEO.  This rocket, using motors designed to be low-cost, would weigh about 8 tonnes at liftoff - about 60% as much as just one solid strap-on motor on a Delta 2 rocket.  It would stand less than 12 meters tall and would be 0.813 meters in diameter - still smaller than a Delta 2 GEM (see comparison image).  It would also produce some high-g loads, but that almost seems inevitable for such light payloads.

 - Ed Kyle

Another possibility to consider is the U.S. Army SWORDS project, set to start flying, in some test form, perhaps in 2014.  Its goal is 25 kg to LEO for $1 million.  It is a LOX/Methane machine being developed by KT Engineering of Huntsville, Alabama.

 - Ed Kyle

[Ed LeBouthillier]

Another possibility to consider is the U.S. Army SWORDS project, set to start flying, in some test form, perhaps in 2014.  Its goal is 25 kg to LEO for $1 million.  It is a LOX/Methane machine being developed by KT Engineering of Huntsville, Alabama.

Yeah, there are two similar programs: MNMS and SWORDS. I haven't figured out why.

MNMS [http://www.dynetics.com/services/space/space-propulsion/smdccolsa-multipurpose-nano-missile-system-mnms]

SWORDS [www.smdc.army.mil/FactSheets/SWORDS.pdf]

Probably just inter-departmental bickering...or else different contractors trying suckle from the government teat....

Neither project will probably ever see the light of day, I'm guessing. But I hope I'm wrong.

Ed L

[cpooley]

After long absence, getting back in (hi, Ed).

I think the cost of a small launcher is 90% the cost of the infrastructure and culture in which it is developed.  One of my slogans is that the most expensive part of the first Microlaunchers rockets is the shop to do it in.  But if anyone is hired, then that will be.

So $1 million or $10 million will depend on who is doing it.

The cost can be in two categories:  the "nuts and bolts" --the bill of materials and direct assembly cost, then the operational costs of doing a launch.

They occur at different times and can be controlled separately.  For example no license or insurance to build the rockets.  That comes in to play when launching.

[Ed LeBouthillier]

Essentially, what I would propose is to take a ring of simple non-TVC solids, providing a good balance of impulse/$, with the core providing TVC, and sized so that upon SRM burnout the core velocity and T:W are adequate.

I've started looking at this a bit and it doesn't come together easily yet.

Are there any particular constraints on which liquid motors can be used? As I'm looking at it, the likely only way that the TRM-3500 will work is with a hefty nozzle extension....even then I'm not sure.

Ed L

[Kaputnik]

That's a good point- as we try to extend the range over which the core is used, its expansion ratio becomes non-optimal. Shame we can't just stick an SSME on there!

Do we have any likely candidates for cheap solids- or is that hoping for too much? Is there anything useful that could be brought in from the world of high-powered model rocketry?

[Ed LeBouthillier]

That's a good point- as we try to extend the range over which the core is used, its expansion ratio becomes non-optimal. Shame we can't just stick an SSME on there!

Hey, if you want to budget it into the design, I can design in an SSME. It doesn't cost *ME* anything to design it in ;-)

Do we have any likely candidates for cheap solids- or is that hoping for too much? Is there anything useful that could be brought in from the world of high-powered model rocketry?

Not off hand. My big problem right now is the central core and its overal efficacy. Once I have a core that seems to work, then I'll consider adding some solids to complement the core stage.

[deltaV]

Yeah, there are two similar programs: MNMS and SWORDS. I haven't figured out why.

MNMS [http://www.dynetics.com/services/space/space-propulsion/smdccolsa-multipurpose-nano-missile-system-mnms]

SWORDS [www.smdc.army.mil/FactSheets/SWORDS.pdf]

Probably just inter-departmental bickering...or else different contractors trying suckle from the government teat....

There's also a DARPA "ALASA" program: http://en.wikipedia.org/wiki/DARPA_ALASA_program . Two programs doing similar things can be helpful (see the F-35 program for the alternative) but three seems on the excessive side.

Both VirginGalactic and XCOR are planning small satellite launchers using their WhiteKnightTwo and Lynx aircraft respectively.