Author Topic: All Solid Motor Antares  (Read 27923 times)

Offline edkyle99

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All Solid Motor Antares
« on: 08/21/2015 02:29 PM »
This past Spring, several news reports indicated that ATK had made a proposal to Orbital (pre-merger) for creating an all-solid motor Antares launch vehicle.  This was an alternative to the ultimate RD-181 choice. 
http://aviationweek.com/blog/orbital-eying-atk-solid-propulsion-system-antares-first-stage-1

I had assumed that the proposal involved two solid motors stacked to replace the existing liquid first stage.  These would have been large, heavy motors, however - heavier even than STS SRB segments with which ATK has experience. 

A recent bit of information has indicated that at least one ATK proposal used three motors to replace the first stage.  These appear to have been roughly SRB diameter (probably a bit fatter than SRB), but likely composite case and a bit shorter than an SRB segment (which actually consisted of two steel segments joined at the factory before propellant loading).  There would have been two roughly equal-size motors for the first and second stages, with a bigger nozzle on the second stage.  The third stage would have been the same diameter, but about half as long.  A Castor 30XL would have been the fourth stage.  The rocket would likely have been about the same height as Antares 200 .

Such a design would have provided lighter weight motors to handle at the launch site.  The biggest motors would have had about as much propellant (perhaps a bit more) as the proposed Ariane 6 P120 motors, and so would have weighed less than an SRB segment.  My guess is that this proposal had some synergy with the proposed Stratolaunch motors.

My guess is that such a rocket would have been able to boost 8 tonnes or more to a 51.6 deg LEO.  My guess is also that the development time needed to create the new motors may have been a reason why the idea was not pursued, even after Orbital merged ATK.

 - Ed Kyle 

Offline hkultala

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Re: All Solid Motor Antares
« Reply #1 on: 08/21/2015 02:53 PM »
All-Solids would also mean no fueling on pad, so the transporter vehicle would have needed to be able to transport much heavier vehicle to the launch pad. Might have meant constructing a totally new launch pad.

Current antares is something close to 50 tonnes when transported to pad?

All-solid would be more than 250 tonnes?


Offline TrevorMonty

Re: All Solid Motor Antares
« Reply #2 on: 08/21/2015 03:11 PM »
A statement Orbital issued about RD180 domestic engine hearing, suggested they would have a domestic powered EELV by 2019. They praised Blue and it's engines in statement.
 My guess is solid 1st stage/ stages with BE3 upper stage. The only issue is large solids at Wallops,  which Jim says is a no go.

The BE3 US may even be supplied by Blue. They already have basis of a US in New Shepard, switch to BE3U and strip out all the reusability parts.

Offline edkyle99

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Re: All Solid Motor Antares
« Reply #3 on: 08/21/2015 09:34 PM »
All-Solids would also mean no fueling on pad, so the transporter vehicle would have needed to be able to transport much heavier vehicle to the launch pad. Might have meant constructing a totally new launch pad.

Current antares is something close to 50 tonnes when transported to pad?

All-solid would be more than 250 tonnes?
My guess is that once fully stacked it would have weighed more than 350 tonnes, maybe even 400-ish tonnes.    Still only 80% or so as heavy as a Falcon 9 v1.1.  It would had to have been stacked on the pad one piece at a time, as Minotaur is, ending the horizontal transport of an entire vehicle. 

 - Ed Kyle 
« Last Edit: 08/21/2015 09:36 PM by edkyle99 »

Offline ArbitraryConstant

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Re: All Solid Motor Antares
« Reply #4 on: 08/21/2015 11:46 PM »
My guess is solid 1st stage/ stages with BE3 upper stage.
Optional depending on launch? They already have the Castor 30.

How would it grow past Atlas V 401 territory?

Offline Space Ghost 1962

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Re: All Solid Motor Antares
« Reply #5 on: 08/22/2015 01:51 AM »
I had assumed that the proposal involved two solid motors stacked to replace the existing liquid first stage.  These would have been large, heavy motors, however - heavier even than STS SRB segments with which ATK has experience.

Why I discounted it when you brought it up, was both due to the launch site requirements (overpressure) and the difficultly in transport/assembly of such solids - the requirements to handle such push the limits of what you can do.

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A recent bit of information has indicated that at least one ATK proposal used three motors to replace the first stage.  These appear to have been roughly SRB diameter (probably a bit fatter than SRB), but likely composite case and a bit shorter than an SRB segment (which actually consisted of two steel segments joined at the factory before propellant loading).  There would have been two roughly equal-size motors for the first and second stages, with a bigger nozzle on the second stage.  The third stage would have been the same diameter, but about half as long

More believable but still difficult to bring off for same reasons. Thanks for bring up the topic though.

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Such a design would have provided lighter weight motors to handle at the launch site.  The biggest motors would have had about as much propellant (perhaps a bit more) as the proposed Ariane 6 P120 motors, and so would have weighed less than an SRB segment.

Please note the P120 motors are to be cast, like other solids (Vega, Ariane), near the launch site. Where would this happen around Wallops/CCAFS/VBG/other?

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My guess is also that the development time needed to create the new motors may have been a reason why the idea was not pursued, even after Orbital merged ATK.

Agreed. Also doubt they would have an easy time explaining to the MARS backers walking away from a still new, state financed LRE pad that would not work for such.

Might have meant constructing a totally new launch pad.

Absolutely. On "hard" ground, not swampland. Give up on horizontal integration too. And most optimal be something like is done for Vega/others/Kodiak. Also, consider transport to launch site.

My guess is that once fully stacked it would have weighed more than 350 tonnes, maybe even 400-ish tonnes.    Still only 80% or so as heavy as a Falcon 9 v1.1.  It would had to have been stacked on the pad one piece at a time, as Minotaur is, ending the horizontal transport of an entire vehicle. 

That light? Was my bottom number. Yes to assembly, and once you've assembled all such,  you might as well integrate the payload as well vertically.

My guess is solid 1st stage/ stages with BE3 upper stage.
Optional depending on launch? They already have the Castor 30.

How would it grow past Atlas V 401 territory?

Yes, the best growth option would be a LRE second stage, both for iSP for GSO/other, restartable for more than LEO, payload growth much like other enhanced US in scale to size of stage increase.

Think of Ariane 6 PPH for growth options / limitations / cost structures.

Offline TrevorMonty

Re: All Solid Motor Antares
« Reply #6 on: 08/22/2015 02:59 AM »
A new Canaveral pad would help with GSO missions plus be able to support solids.

Offline edkyle99

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Re: All Solid Motor Antares
« Reply #7 on: 08/22/2015 03:13 AM »
Please note the P120 motors are to be cast, like other solids (Vega, Ariane), near the launch site. Where would this happen around Wallops/CCAFS/VBG/other?
Motors would likely have been cast in Utah, just like the SRB segments, and Castor 30XL, etc..  They could have been rail transported, then transloaded for road or barge for the final run to the pad. 

Yes, road.  They drive the heavier SRB segments on roads on a special 12-axle transporter in Utah before lifting them onto rail cars. 

Wallops would have needed new infrastructure for this, of course.  It would have been easier if Orbital or ATK had specified KSC as the launch site.

I would still like to see such a rocket.  All-solid for CRS.  Replace Castor 30XL with a high energy stage and it's 6.5 tonnes to GTO.

 - Ed Kyle 
« Last Edit: 08/22/2015 03:20 AM by edkyle99 »

Offline Space Ghost 1962

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Re: All Solid Motor Antares
« Reply #8 on: 08/22/2015 04:00 AM »
Please note the P120 motors are to be cast, like other solids (Vega, Ariane), near the launch site. Where would this happen around Wallops/CCAFS/VBG/other?
Motors would likely have been cast in Utah, just like the SRB segments, and Castor 30XL, etc..  They could have been rail transported, then transloaded for road or barge for the final run to the pad. 

Yes, road.  They drive the heavier SRB segments on roads on a special 12-axle transporter in Utah before lifting them onto rail cars.

Having just been through I-80 in Utah and Wyoming, where its under significant repair/upgrade, I'm sure it won't be by road to Wallops ;)

Not all rail can accept such loads as you know. And you're talking segments not monolithic's. I'm very sure you won't see commercial segmented solids, due the hazards of assembly and health. You can waive these for national imperatives (in some cases just barely), but forget it in the "commercial world". EU has related issues too.

So we still have the weight issue as I see it.
 
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Wallops would have needed new infrastructure for this, of course.  It would have been easier if Orbital or ATK had specified KSC as the launch site.

Unlikely for the reasons Wallops was chosen in the first place.

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I would still like to see such a rocket.  All-solid for CRS.  Replace Castor 30XL with a high energy stage and it's 6.5 tonnes to GTO.

I can understand this. US has significant expertise here. And for any significant use of solids, weapons and unmanned launches make the best sense. All domestic. And with similar rational to Ariane.

Offline Lars-J

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Re: All Solid Motor Antares
« Reply #9 on: 08/22/2015 04:57 AM »
I would still like to see such a rocket.  All-solid for CRS.  Replace Castor 30XL with a high energy stage and it's 6.5 tonnes to GTO.

I can understand this. US has significant expertise here. And for any significant use of solids, weapons and unmanned launches make the best sense. All domestic. And with similar rational to Ariane.

I think a solution such as this only makes sense from a "if all you have is a hammer, every problem is a nail" kind of approach. It is not optimal.

And the US having significant expertise in solids is not the issue. More of it is not needed, if anything the balance should be shifted to developing liquid propulsion expertise. And fortunately such a shift *is* happening, even if OrbitalATK sadly is not a part of it.

Offline john smith 19

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Re: All Solid Motor Antares
« Reply #10 on: 08/22/2015 12:30 PM »
Looking at some of the pros and cons.

If you've already got a solid in the architecture adding a few more seems pretty simple, but then again going the other way sounds ok too.

It retains experience of building large solids which is vital to ICBM work  I asked on another thread about the idea of saving money by block casting SRB boosters in the Utah desert and storing them upright in big holes, ICBM style.  Another poster, who seemed pretty knowledgeable on the subject said that in fact civilian solids have a completely different composition to the ICBM mix and they would "slump." That makes such an argument quite doubtful. It's only a useful argument in Congress,and it does not seem to stand up to close inspection.

Solids can be more flexible than people might think. 10:1 throttling ratios have been demonstrated using a pintle in the nozzle. But they do have much higher vibration than liquids and unless you cast on site (as most of the Ariane segments are, by about 70 local workers) they are a PITA to transport across country.

They do make excellent weapon systems.

But if you're not building a weapon do you want something that's going to bigger and more difficult to move (unless you mfg on site you've moving a big block of explosive across country) than the equivalent stage + propellant for a liquid system unless you can buy it off the shelf and substantially reduce the development budget (but don't think you can eliminated development).
BFS. The worlds first Methane fueled FFORSC engined CFRP structured A380 sized aerospaceplane tail sitter capable of flying in Earth and Mars atmospheres. BFR. The worlds biggest Methane fueled FFORSC engined CFRP structured booster for BFS. First flight to Mars by end of 2022. Forward looking statements. T&C Apply So, you are going to Mars to start a better life? Picture it in your mind. Now say what it is out loud.

Offline edkyle99

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Re: All Solid Motor Antares
« Reply #11 on: 08/22/2015 03:26 PM »
Having just been through I-80 in Utah and Wyoming, where its under significant repair/upgrade, I'm sure it won't be by road to Wallops ;)

Not all rail can accept such loads as you know. And you're talking segments not monolithic's. I'm very sure you won't see commercial segmented solids, due the hazards of assembly and health. You can waive these for national imperatives (in some cases just barely), but forget it in the "commercial world". EU has related issues too.
As I understand things commercial launch vehicle solid motors already are being road-transported.  Castor 120's and probably 30(XL) motors are driven across country, as I expect are other solid motors.  Castor 30(XL) went not just to Wallops, but also to Arnold in Tennessee for development testing.

How do those AJ-60s and GEM-60s get to the Cape and Vandenberg AFB? 

For that matter, how did/do those higher-energy Peacekeeper and Minuteman missile motors get from builder to silo, and from silo to VAFB for test flights?  How do those Navy SLBMs get from their point of manufacture to submarine bases?   I suspect they are driving down our highways.

 - Ed Kyle

Offline Space Ghost 1962

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Re: All Solid Motor Antares
« Reply #12 on: 08/22/2015 06:15 PM »
I think a solution such as this only makes sense from a "if all you have is a hammer, every problem is a nail" kind of approach. It is not optimal.

It certainly isn't the optimal LV from the GTOW or dry mass fraction. It might be after a few hundred ELV launches gross cost optimal if cast on site and launched to order with optimal pad/facilities as a total cost solution where the design/fabrication costs are significantly shared with necessary weapons systems in the same firm.

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And the US having significant expertise in solids is not the issue. More of it is not needed, if anything the balance should be shifted to developing liquid propulsion expertise. And fortunately such a shift *is* happening, even if OrbitalATK sadly is not a part of it.

You are arguing with past doctrine established with the arrival of large solids starting with Titan/Minuteman. Appreciate the opinion but I don't wish to tilt at your windmills here (settled doctrine), find it rather tedious.

Even with Ed's best arguments for medium solids LV, you'll note he constantly evades the above mentioned necessary economic components to make the scheme work, which to me is irrational because it is terminal to the scheme actually functioning. But because he knows it was elided in the past, he can persist in a "non executable" scheme because circumstances (national security) in theory might change to allow such. Just like you, he has his "tilting at windmills", which I find equally tedious.

Worse is the HSF doctrine allowing crew missions on unstoppable solids, which I can't also dismiss, which are incompletely "made safe" by significant additional cost which cannot ever be recovered unlike in theory recoverable LRE stages might now be - a potentially pending doctrine on the edge of happening now that Ed cannot accept.

All the above is as crisp as I can put it without losing essentials. Pragmatics surround any choice of optimal.

It retains experience of building large solids which is vital to ICBM work  I asked on another thread about the idea of saving money by block casting SRB boosters in the Utah desert and storing them upright in big holes, ICBM style.  Another poster, who seemed pretty knowledgeable on the subject said that in fact civilian solids have a completely different composition to the ICBM mix and they would "slump." That makes such an argument quite doubtful. It's only a useful argument in Congress,and it does not seem to stand up to close inspection.

Much more to it than this but yes they are very different. The real cost sharing is off increased frequency of design/qualification/manufacturing/deployment because weapons systems turnover rate is too slow/costly in comparison. There is no cost sharing of inventory/tooling/etc because you cannot use them interchangeably. Its even worse than the uniqueness of spacecraft/launch vehicle design ala "Legos".

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Solids can be more flexible than people might think. 10:1 throttling ratios have been demonstrated using a pintle in the nozzle. But they do have much higher vibration than liquids and unless you cast on site (as most of the Ariane segments are, by about 70 local workers) they are a PITA to transport across country.

Yes, and with Ed I agree that solids beyond weapons systems do have a point. But I don't agree at all about the evasions WRT transport, to allow assembly in Utah. That has always been stark raving nuts to me.

Mind you the environmental issues WRT solids fabrication in French Guiana, which is NOT technically the same as in the EU, is also an evasion as well. But in theory one can have environmentally sound casting of solids, possibly involving automation, could occur, thus allowing component (non segments) transport for monolithic vehicle component local assembly.

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But if you're not building a weapon do you want something that's going to bigger and more difficult to move (unless you mfg on site you've moving a big block of explosive across country) than the equivalent stage + propellant for a liquid system unless you can buy it off the shelf and substantially reduce the development budget (but don't think you can eliminated development).

Not explosive but combustible, extremely hazardous, environmentally unsound to transport (unless monolithic but then limited in size). You'll never buy it off the shelf, doesn't work that way.

Deveiopment et al can be massively improved too.

Having just been through I-80 in Utah and Wyoming, where its under significant repair/upgrade, I'm sure it won't be by road to Wallops ;)

Not all rail can accept such loads as you know. And you're talking segments not monolithic's. I'm very sure you won't see commercial segmented solids, due the hazards of assembly and health. You can waive these for national imperatives (in some cases just barely), but forget it in the "commercial world". EU has related issues too.
As I understand things commercial launch vehicle solid motors already are being road-transported.  Castor 120's and probably 30(XL) motors are driven across country, as I expect are other solid motors.  Castor 30(XL) went not just to Wallops, but also to Arnold in Tennessee for development testing.

As you know Ed monolithic solids/motors. Please don't spar with me when you know the differences between handling of segments vs finished monolithic stages/motors.

Offline edkyle99

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Re: All Solid Motor Antares
« Reply #13 on: 08/22/2015 07:50 PM »
As I understand things commercial launch vehicle solid motors already are being road-transported.  Castor 120's and probably 30(XL) motors are driven across country, as I expect are other solid motors.  Castor 30(XL) went not just to Wallops, but also to Arnold in Tennessee for development testing.

As you know Ed monolithic solids/motors. Please don't spar with me when you know the differences between handling of segments vs finished monolithic stages/motors.
I thought we were talking about monolithic motors, which would have been used for a solid motor Antares. 

At any rate, rail would be cheaper than road transport regardless of motor type, and barge even cheaper.  KSC and VAFB can receive rail or barge directly.  Wallops cannot (the Antares first stage arrives in the Port of Wilmington and must be trucked on a 95 foot carrier trailer slowly down US 13 a distance of some 150-ish miles, in stages, at night probably).  In my opinion, Wallops was a bad idea for this project from the get-go, but that's probably for another thread.

I'm also not sure I understand your cost discussion in the same message.  Motors cast in Utah or where ever - how  is that different, cost-wise, than entire rockets or rocket stages or rocket engines being built in California or Alabama or Ukraine or Russia and then being shipped to one of the U.S. Coasts?

 - Ed Kyle
« Last Edit: 08/22/2015 08:42 PM by edkyle99 »

Offline Space Ghost 1962

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Re: All Solid Motor Antares
« Reply #14 on: 08/22/2015 10:30 PM »
...
I thought we were talking about monolithic motors, which would have been used for a solid motor Antares. 

As did I until it seemed you were introducing segments to the discussion to make possible transporting Utah castings to Wallops/CCAFS/VBG. Did I have that wrong? I'm sorry if I did. I hear the evasion often.

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At any rate, rail would be cheaper than road transport regardless of motor type, and barge even cheaper.  KSC and VAFB can receive rail or barge directly.  Wallops cannot (the Antares first stage arrives in the Port of Wilmington and must be trucked on a 95 foot carrier trailer slowly down US 13 a distance of some 150-ish miles, in stages, at night probably).  In my opinion, Wallops was a bad idea for this project from the get-go, but that's probably for another thread.
All agreed.

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I'm also not sure I understand your cost discussion in the same message.  Motors cast in Utah or where ever - how  is that different, cost-wise, than entire rockets or rocket stages or rocket engines being built in California or Alabama or Ukraine or Russia and then being shipped to one of the U.S. Coasts?

So why are the motors cast near launch site for Ariane? BTW, if you recall, Aerojet's proposal for large diameter motors involved casting near launch site. Because you avoid transportation costs and limitations on the scale of monolithics due to the means to integrate LV simply due to weight/bulk. Monolithics are much better behaved otherwise.

Likewise, one can do casting and final assembly near launch site for a monolithic motor, as part of the integration of large stacks like suggested in this thread for an all solid Antares. You scale the short range transport, just as in your above mentioned example for road transport of smaller solids to rail/other destination. This obviates the need to provide for the end to end rail transport of hazardous, heavy, bulky cargo that is atypical of more common rail cargo using the transport. Unlike Russia, the rules on such have greatly changed in thirty years, and the costs/risks are larger, if for no other reason, liability coverage/waivers. Not to mention EIS either.

This increases the costs of large (120t+) monolithic motors. Yes you could ship them by barge. Unfeasible from Utah. And as you just pointed out, unfeasible to Wallops end to end.

So lets say, somewhere other than Utah, likely adjoining a sea/ocean/waterway, you cast and barge to CCAFS/VBG. Your added costs are the new facility + staffing + EIS. Transport costs are negligible increases on top of that. However, OA might find this too much to stomach, although its cheap enough to me.

If you only have one launch site (Wallops), you'd put it nearby - costly, and arrange local transport to launch site with special roadway/transport. Then your issues are environmental and regulatory for Virgina - costly. Optional additional roadway/transport to Port Wilmington (very costly). Look at all the help with MARS from the State of Virginia - this would be more. For a LV that might not be "flyable" given flight risks of the already built up shoreline.

Agreed on Wallops being unsuitable for this in general for various reasons. However, counting on heavy solids at both simultaneously CCAFS/VBG (as they'd likely need to) isn't something I'd want to count on for my commercial LV either.

Offline edkyle99

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Re: All Solid Motor Antares
« Reply #15 on: 08/23/2015 01:23 AM »
...
I thought we were talking about monolithic motors, which would have been used for a solid motor Antares. 

As did I until it seemed you were introducing segments to the discussion to make possible transporting Utah castings to Wallops/CCAFS/VBG. Did I have that wrong? I'm sorry if I did. I hear the evasion often.
Monolithic motors of the proposed size could be transported by rail.  Each complete motor would weigh less than one SRB segment, which was of course rail-transported.  Of course the problem with Wallops would be the final bit from whatever railhead is used (there is a railroad a few miles inland that runs south from Wilmington I think, though it would need upgrading) to the launch pad.

 - Ed Kyle

Offline Space Ghost 1962

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Re: All Solid Motor Antares
« Reply #16 on: 08/23/2015 05:30 PM »
...
I thought we were talking about monolithic motors, which would have been used for a solid motor Antares. 

As did I until it seemed you were introducing segments to the discussion to make possible transporting Utah castings to Wallops/CCAFS/VBG. Did I have that wrong? I'm sorry if I did. I hear the evasion often.
Monolithic motors of the proposed size could be transported by rail.  Each complete motor would weigh less than one SRB segment, which was of course rail-transported.  Of course the problem with Wallops would be the final bit from whatever railhead is used (there is a railroad a few miles inland that runs south from Wilmington I think, though it would need upgrading) to the launch pad.

 - Ed Kyle

Carefully took the time to research this, from the total weight of each stage, to the actual rail passage, to final delivery to the Wallops pad. Turns out you are more right than you know on being able to deliver a complete all solid Antares as described in this thread. I can even tell you how long it will take, and the cost/insurance/waivers you'll need, as well as the routes and stops.

As a means to prove this, you can find ample evidence of other heavy cargo (in this case, M1-A1 Abrams tanks, they are about 70t each, two per car, six per train) across the routes:
Image of 140T Load on route

In short, yes, as long as they are composite not steel cased/supported stages/motors of the kind implied above. So I was wrong.

Also did the work on range safety for such at Wallops. The limiting factor are the linear charges to terminate flight of such a vehicle. It isn't even close.

So the primary issue is cost of a new launch site, facilities, and staff.

Offline Lars-J

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Re: All Solid Motor Antares
« Reply #17 on: 08/24/2015 11:10 PM »
I think a solution such as this only makes sense from a "if all you have is a hammer, every problem is a nail" kind of approach. It is not optimal.

It certainly isn't the optimal LV from the GTOW or dry mass fraction. It might be after a few hundred ELV launches gross cost optimal if cast on site and launched to order with optimal pad/facilities as a total cost solution where the design/fabrication costs are significantly shared with necessary weapons systems in the same firm.

That's a lot of IF's you have there. And if you need hundreds of launches to make it "gross cost optimal" compared to other non-solid or partially solid launchers (which would also presumably be able to lower their costs with hundreds of launches), isn't that already an admission of failure from a cost perspective?

Offline Space Ghost 1962

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Re: All Solid Motor Antares
« Reply #18 on: 08/24/2015 11:46 PM »
Spaceflight is the biggest collection of "if"s" ever.

Offline TrevorMonty

Re: All Solid Motor Antares
« Reply #19 on: 09/22/2015 09:25 PM »
The Ariane6 design maybe a better option for OA as it relies heavily on SRBs but also gets performance benefits of liquid booster.

OA could develop a Ariane 62 (5t GTO) equivalent with BE3 and their SRBs.
Booster would be 2x BE3 plus 4x60t SRBs. Use a BE3 powered upper stage for GTO missions or Castor for Cygnus ISS missions.

 Going to 6 x SRBs could take it to >7t GTO.

Using 60t SRBs makes transporting easier plus they may benefit from new Atlas and Vulcan SRB development.

 There are no prices for BE3 but I would expect it to be well <$5M.

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