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.
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?
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?
Quote from: Kaputnik on 02/17/2013 01:01 pmManual 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).
Thoughts, anyone?
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 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.
Quote from: Ed LeBouthillier on 02/17/2013 02:27 pmThe 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?
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).
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.
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.
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.
It might be worth considering an air launch from a small aircraft.
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).
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.
Quote from: Kaputnik on 02/17/2013 04:35 pmThe 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 imagine that some middle stage would still be required to bridge the gap between the GPS cut-off and the final spun stage.
What I would propose discussing is the use of primarily ordnance-based stages to create a comparatively low performance vehicle.
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.
Quote from: Solman on 02/19/2013 12:10 am 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
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.
A strict interpretation of "lowest cost launcher" might include only the launch vehicle and not the entire system.
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.
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?
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 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.
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.
a gun. HARP fired around 1,000 projectiles up to 66 km. All for a few million dollars. And so on.
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.
Quote from: Solman on 02/19/2013 12:10 am 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,
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.
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.
Quote from: Ed LeBouthillier on 02/17/2013 03:43 pmAlright 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
Quote from: Solman on 02/19/2013 01:51 am 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?
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)
To calculate things accurately you need to know atmospheric model (densities at any altitude), spacecraft's reference area and drag coefficient.
Ahh, that's why the name looked familar Good stuff!
Quote from: Solman on 02/19/2013 12:10 am A strict interpretation of "lowest cost launcher" might include only the launch vehicle and not the entire system. Expensive self-delusion.Quote 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.Quote 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 ...
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.
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.
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 ).
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).
Quote from: Robotbeat on 02/19/2013 08:20 pmOf 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
I apologize if I came off "testy."
The Air Force may deploy laser equipped aircraft by 2015.
Quote from: R7 on 02/19/2013 09:04 amQuote from: Solman on 02/19/2013 12:10 am A strict interpretation of "lowest cost launcher" might include only the launch vehicle and not the entire system. Expensive self-delusion.Quote 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.Quote 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?
Quote from: Solman on 02/19/2013 06:04 pm 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.
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.
Quote from: RocketmanUS on 02/19/2013 09:33 pm1st 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...
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?
Link please to specs and prices.
Quote from: Solman on 02/19/2013 06:04 pmQuote from: R7 on 02/19/2013 09:04 amQuote from: Solman on 02/19/2013 12:10 am A strict interpretation of "lowest cost launcher" might include only the launch vehicle and not the entire system. Expensive self-delusion.Quote 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.Quote 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
Quote from: Jim on 02/19/2013 09:14 pmQuote from: Solman on 02/19/2013 06:04 pm 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.
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.
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.
Quote from: Robotbeat on 02/19/2013 09:27 pmChemical 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.
Quote from: Solman on 02/19/2013 11:37 pmAlso, 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.
Quote from: Jim on 02/19/2013 09:14 pmQuote from: Solman on 02/19/2013 06:04 pm 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/
Quote from: Jim on 02/19/2013 11:40 pmQuote from: Solman on 02/19/2013 11:37 pmAlso, 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.
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....
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.
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.
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?
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.
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.
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...
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?
...Do you think the concept of using HELLADS to accelerate small payloads to orbit is fatally flawed in some way?
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
Quote from: Solman on 02/20/2013 12:11 amThe 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
Quote from: Solman on 02/20/2013 12:11 am...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.
Quote from: Solman on 02/20/2013 12:11 amdo 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 QuoteDo 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).
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?
Quote from: Robotbeat on 02/20/2013 02:32 pmQuote from: Solman on 02/20/2013 12:11 am...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.
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.
Quote from: RanulfC on 02/20/2013 02:33 pmIt 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.
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.
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.
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.
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).
Do you have a quote on what an J-2, LCPE or RL-10B-2 might cost? I think they're fairly pricey.
Quote from: Kaputnik on 02/20/2013 07:30 pmObviously 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.
Quote from: Ed LeBouthillier on 02/20/2013 07:42 pmQuote from: Kaputnik on 02/20/2013 07:30 pmObviously 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
And personally I'd like to see what we could come up with for a single CubeSat launcher either singly or repeatably...
Quote from: RanulfC on 02/20/2013 09:08 pmAnd 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
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.
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 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.
Quote from: Robotbeat on 02/21/2013 01:50 amI'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?
Quote from: Patchouli on 02/21/2013 02:29 amWhat 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.
Quote from: brtbrt on 02/21/2013 03:01 amQuote from: Patchouli on 02/21/2013 02:29 amWhat 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?
Quote from: RocketmanUS on 02/21/2013 04:39 amQuote from: brtbrt on 02/21/2013 03:01 amQuote from: Patchouli on 02/21/2013 02:29 amWhat 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.
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.
Quote from: brtbrt on 02/21/2013 04:07 amEd, 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.
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
The liming factor would be availability and cost of F-15 when trying to design lowest cost orbital launcher.
Mig jets might be more attainable and cheaper. There are some privately held ones, you may be able to rent it or something.
Quote from: Robotbeat on 02/21/2013 02:34 pmMig 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.htmlThose 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.
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?
Correct. US just sold Saudis 80+ F-15s for $~30B so those are pretty steep.
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.
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...
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).
Quote from: Robotbeat on 02/25/2013 01:04 amBTW, 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.htmlThe 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
Wasn't Lambda 4S's payload quite a bit larger than Vanguard's? Encyclopedia Astronautica quotes about 60 lb to LEO vs. 20.
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.
We have it on a good authority that one can't really do an orbital launcher with under $10M in development funding.
What i'm wondering is if the actual hardware cost, at least for an expendable system, would even play a first order role in closing the business case for a nanosat launcher.
What would be expected range costs for nanosat launcher? Where would potential launch sites be?
The more remote the better, to a point, I guess. Could the costs be reduced to pretty much filing a NOTAM? Andøya in Norway comes to mind, might be a good place to do SSO/polar launches towards north without much risk/disturbance to anybody.
OK, I've been delving into the details of stage 3.
Helium tank should be carbon-fiber-overwrapped (makes it significantly lighter) and more round-ish. This is basically what everyone does, including amateur folk.
It's not an expensive technology (amateur rocketeers sometimes use the carbon fiber tanks from paintball guns). Or, if you want to stick with metal, you can stick it in the liquid oxygen tank to reduce its mass. I don't know if you have a heat-exchanger system for the helium pressurant, but that would also reduce its mass significantly. As you diagram is right now, the helium tank looks to be quite massive.
But, this was a worthy experiment to consider the use of this motor in cost reduction. We could begin to estimate costs from at the current level of detail, but I think that the original intent is to go smaller.Is that correct, Mr. Kaputnik? Do you want to consider a smaller launcher? What direction do you want to go? I think we should consider a smaller launcher before we start breaking things down for cost estimation.
Apologies for being absent from the thread for a while- rather busy at work.
Essentially, what I would propose is to take a ring of simple non-TVC solids, providing a good balance of impulse/$, 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.
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 $1 million. It is a LOX/Methane machine being developed by KT Engineering of Huntsville, Alabama.
Essentially, what I would propose is to take a ring of simple non-TVC solids, providing a good balance of impulse/$, with the core providing TVC, and sized so that upon SRM burnout the core velocity and T:W are adequate.
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?
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....