Quote from: a_langwich on 05/25/2016 07:35 pmDo we know if the side GEMs fit on both the medium and the heavy? The heavy will be closer/close to the Stick?And do the side GEMs provide as big a benefit if the first stage is essentially fixed duration, no throttling? I've yet to see any drawings of the Heavy configuration. The first and GEMs stage will likely "throttle", via. propellant grain shaping. They will provide all the thrust they can muster at first, then probably tail off for Max-Q and toward the end-of-burn. See the SRB and GEM-60 thrust profiles below for examples. - Ed Kyle
Do we know if the side GEMs fit on both the medium and the heavy? The heavy will be closer/close to the Stick?And do the side GEMs provide as big a benefit if the first stage is essentially fixed duration, no throttling?
Quote from: edkyle99 on 05/25/2016 07:53 pmQuote from: a_langwich on 05/25/2016 07:35 pmDo we know if the side GEMs fit on both the medium and the heavy? The heavy will be closer/close to the Stick?And do the side GEMs provide as big a benefit if the first stage is essentially fixed duration, no throttling? I've yet to see any drawings of the Heavy configuration. The first and GEMs stage will likely "throttle", via. propellant grain shaping. They will provide all the thrust they can muster at first, then probably tail off for Max-Q and toward the end-of-burn. See the SRB and GEM-60 thrust profiles below for examples. - Ed KyleI guess my thought, and it was just a fuzzy guess, was that when you mounted SRBs to an Atlas V, the liquid engines could be throttled a bit to reduce the acceleration at inappropriate times (ie maxQ and near SRB burnout?). This throttling, then, would yield more fuel in the tank for later in the flight. I haven't actually checked...does the first stage of an Atlas burn any longer or stage any higher/faster when the solids are used? I guess it depends on whether the strap-ons are being used for a high energy mission or a heavy lower energy mission.The throttling you mentioned for SRBs is cast into the solid, so the first stage without an add-on must act exactly like a first stage with add-on(s). Unless you assume the burn profile is tailored each mission, which I wouldn't doubt is possible but do doubt could ever be cost-effective. And my question was, does this inflexible burn pattern limit the usefulness of the strap-ons? It seems like a slightly different burn pattern would be useful to take advantage of the strap-ons.
Quote from: a_langwich on 05/25/2016 07:46 pmIf that turns out to be the case (no pun intended, but there it is), I don't see this vehicle getting the economies of scale needed to compete.Nor do I really think it's a wise use of money to _start_ another EELV, when the existing two families are already going to be leaning heavily on commercial sales to keep their launch rate up.In addition to the upper stage being shared with other Blue projects, the economies of scale would come, eventually, from from sharing the booster segments with SLS. That would mean shared engineering, production, and launch processing resources and personnel. - Ed Kyle
If that turns out to be the case (no pun intended, but there it is), I don't see this vehicle getting the economies of scale needed to compete.Nor do I really think it's a wise use of money to _start_ another EELV, when the existing two families are already going to be leaning heavily on commercial sales to keep their launch rate up.
Quote from: a_langwich on 05/26/2016 03:49 amThe throttling you mentioned for SRBs is cast into the solid, so the first stage without an add-on must act exactly like a first stage with add-on(s). Unless you assume the burn profile is tailored each mission, which I wouldn't doubt is possible but do doubt could ever be cost-effective. And my question was, does this inflexible burn pattern limit the usefulness of the strap-ons? It seems like a slightly different burn pattern would be useful to take advantage of the strap-ons.All other OrbitalATK launchers including sounding rockets are commonly tailored for each mission. Surplus GS motors are not mission tailored and is only adjusted in OA's commercial made upper stages on those missions
The throttling you mentioned for SRBs is cast into the solid, so the first stage without an add-on must act exactly like a first stage with add-on(s). Unless you assume the burn profile is tailored each mission, which I wouldn't doubt is possible but do doubt could ever be cost-effective. And my question was, does this inflexible burn pattern limit the usefulness of the strap-ons? It seems like a slightly different burn pattern would be useful to take advantage of the strap-ons.
And didn't you indicate earlier that the CBS were steel casing Dark Knight 1.5x-length segments?
Quote from: edkyle99 on 05/25/2016 07:50 pmQuote from: a_langwich on 05/25/2016 07:46 pmIf that turns out to be the case (no pun intended, but there it is), I don't see this vehicle getting the economies of scale needed to compete.Nor do I really think it's a wise use of money to _start_ another EELV, when the existing two families are already going to be leaning heavily on commercial sales to keep their launch rate up.In addition to the upper stage being shared with other Blue projects, the economies of scale would come, eventually, from from sharing the booster segments with SLS. That would mean shared engineering, production, and launch processing resources and personnel. - Ed KyleYes, I think the Blue Origin upper stage will not be a problem on cost.SLS doesn't help much on costs, I think. In the timeframe of interest, SpaceX plans to be launching 30+ times a year, and ULA even plans 12-16 launches including commercial flights. In that context, 2 additional SRBs, or 4 if it's a busy year, isn't going to shift the cost curve. It may keep people busy where they would otherwise have been idled. I guess one assumption here is that Orbital-ATK employees would handle launch processing for SLS SRBs? In that regard, I can see why NASA might welcome the Orbital-ATK LV. If it shifts a cost curve, it would be on the SLS side, not the Orbital-ATK side. But I'm mystified by the Air Force support...they don't get anything but a billion-ish dollar bill, and then another launch vehicle to get pressured to support by throwing launches at it. Or, if DoD doesn't throw launches at it, Orbital-ATK adds another LV to its impressive collection of vehicles that haven't launched in a few years but are still available if anyone wants to order one.I still think, and I'm greatly in the minority here apparently, that the Air Force would do / have done better to fund the AR-1 the way Congress told them. Rather than developing this LV from scratch, Antares could easily be adapted into an EELV-competitor using an AR-1, and perhaps a BE-3 upper stage option. Commonalities with the CRS-2 hardware would have helped economies of scale. But that Humpty Dumpty looks sadly scrambled now.I wonder if the Air Force will try to modernize the Minuteman solids...there's a bit of talk about spending a fair amount sprucing up the aging deterrence weapons. Seems like a better use of Air Force-to-ATK money than this, IMO.
Quote from: russianhalo117 on 05/26/2016 04:30 amQuote from: a_langwich on 05/26/2016 03:49 amThe throttling you mentioned for SRBs is cast into the solid, so the first stage without an add-on must act exactly like a first stage with add-on(s). Unless you assume the burn profile is tailored each mission, which I wouldn't doubt is possible but do doubt could ever be cost-effective. And my question was, does this inflexible burn pattern limit the usefulness of the strap-ons? It seems like a slightly different burn pattern would be useful to take advantage of the strap-ons.All other OrbitalATK launchers including sounding rockets are commonly tailored for each mission. Surplus GS motors are not mission tailored and is only adjusted in OA's commercial made upper stages on those missionsSo you think the burn profile of the CBS would be changed if a mission involved add-on solids, or even between a heavy LEO with add-on solids vs a light, high-energy mission with add-on solids? A custom booster for each mission? That seems like the opposite of "Common".
My guess is that in the end one might be developed but not the other.
Isn't it more logical to make a heavy with a Castor 900-Castor 300 and BE-3UEN?
That will be less of a pencil rocket.
Let me first note that all this is speculation from my side.So the second stage is the one segment Castor 300; the first stage is either the two segment Castor 600 or the four segment Castor 1200. The Lockheed Martin and ULA Athena 3 concept would use a Castor 900, could a three segment CBM be a Castor 900?. Could the Castor 1200 be the same size as the SLS five segment RSRB?Isn't it more logical to make a heavy with a Castor 900-Castor 300 and BE-3UEN?That will be less of a pencil rocket. If it would be a composite casing I know the following about the production process.Most likely they will go for carbon fiber composite casing segments that are filament wound around a mandrel. This mandrel has to be segmented otherwise it can't be taken out of the produced casings. I think they design a mandrel system that can be assembled in four configurations:- Castor 300, single segment, on one side the nozzle on the other side the top bulkhead with igniter.- Lower segment, on one side the nozzle on the other side a segment connection interface.- Top segment, on one side the top bulkhead with igniter on the other the segment connection interface. - Middle segment, on both sides a segment connecting interface.With building blocks for 1) the nozzle, 2) top bulkhead and 3) a connection interface all configurations can be build on the same tooling. They only assemble the mandrel differently. I think Orbital ATK will make one or two winding machines for both the SLS and Solid EELV. The segments have different casting configurations, for this different casting molds are required. I don't know enough about the casting process to make a conclusion on how they will do this. I expect that Orbital ATK has used this technology on multiple projects already. I think they even configure different casing lengths with this method (Orion 50; Castor 120/30; GEM family). On development cost. The AR-1 development will cost at least 1 billion. All high power liquid high performance engine development programs have development costs above a billion dollars. I expect OrbitalATK can develop the CBS system for a lot less then 0,5 billion. And the cost of launching SLS will go down when it is developed and used. I read about Brazilian VS sounding rocket metal casing production and the development of the carbon composite S50 (German casing). The S40/ S43 casings took more than a month to produce, the composite S50 casings can be produced in about a week or so. This saves a lot of production costs. I think the same is true for the RSRM and CBS segments. I even expect the production of CBS segments to be a lot cheaper than the refurbishment of RSRM segments. The CBS can be produced using robots and without air supply systems. The insulation of the RSRM segments have to be removed and replaced by hand. Also the workers have to use external air supply because of the Chlorine oxides and hydrogen chlorides that have been produced during the burning of the AP propellant.I think the CBS development could earn itself back very quickly also when only SLS launches are taken into consideration. For AR-1 that has a doubtful use, because SpX is developing Raptor and BO is developing BE-4 on their own funding. I think it is certain it will not repay itself. I also hope (not my concern since I'm from Europe) that Nasa will take in consideration BE-4 and Raptor as replacement of the leftover RS-25 STS engines. When considering the billion dollar production restart program of RS-25 engines. I wonder what a billion dollar Big Fat Rocket COTS program can lead to. (sorry for being partially off topic )
Quote from: Lobo on 03/04/2016 06:16 pmBut, to consider. FH with all 3 cores recovered would probably only have a performance similar to a single core of this Orb-ATK LV. Performance that will require a heavy version of the Orb-ATK solid LV would probably require at least an expendable FH central core. So the price points might be single-core solid LV vs. FH with all 3 recoverd cores. Or tri-core solid LV vs. FH with expendable central core.We don't know the "recycle" time/economics yet. There have been recent hints that this might be quite different then we were led to believe with Shuttle. If "once in a blue moon" FH NSS launches w/o reuse from F9 payload business contributing, then a solid vehicle that is gradually produced/stacked economically might compete favorably. It gets around the "minimum number of launches" per annum issues that ULA has.Now, the part I completely don't buy is the hydrolox US. OA has no experience with LH - they chickened out of it before with Antares (which was wise in retrospect), and I can't see them outsourcing this need, much less having the launch frequency to "keep alive" a hydrolox US in house.Best I could see is sharing it with Antares, but once you'd have two LV (Antares LV + solid LV), there would be enormous pressure to have just one LV, so one would be back to all the same problems as before, which is why they didn't do a solid Antares nor a LH US for it.So all this seems to be is a backup LV paper concept for if ULA trips and falls flat on its face
But, to consider. FH with all 3 cores recovered would probably only have a performance similar to a single core of this Orb-ATK LV. Performance that will require a heavy version of the Orb-ATK solid LV would probably require at least an expendable FH central core. So the price points might be single-core solid LV vs. FH with all 3 recoverd cores. Or tri-core solid LV vs. FH with expendable central core.
The NGL 500-series drawings suggest the possibility for common segment lengths, all based roughly on the longest Shuttle SRB cylindrical segment casing that was part of the aft segment. Another factor consistent with this SRB-segment length are the supposed gross weights of the motors suggested by the Castor names, as discussed upthread. This does not tell me whether the segment casings are steel or composite, nor does it tell us if the propellant is PBAN or HTPB. I would not be surprised by any of these outcomes. - Ed Kyle
SpaceX ULA Orbital-ATKMEDIUM Falcon 9 Vulcan Centaur NGL-IntermediateHEAVY Falcon Heavy Vulcan-Aces NGL-Heavy
Third, he notes that in addition to LC 39B, Orbital/ATK is considering VAFB SLC 2 as a launch site.
Quote from: edkyle99 on 05/28/2016 02:00 pm Third, he notes that in addition to LC 39B, Orbital/ATK is considering VAFB SLC 2 as a launch site. Reading that article, it seems Liberty also planned to use LC-39B. Did that plan include using the (now SLS) MLP and CTs? But presumably stacked in a different high bay than SLS? Does not having an MLP handy (say, if the Orbital-ATK solid is being stacked and sent to the pad) interfere with stacking operations for the other rocket (SLS)? Would you stack the EELV off to the side, on top of one of the SLS SRB exhaust ports on the MLP, and then work to adapt the launch umbilicals to this location? Or just hang it over the larger middle opening? Presumably the Orbital-ATK umbilicals are integrated into the NASA mobile launcher? And either a milkstool or a separate set of upper stage umbilicals for the medium as compared to heavy?
still extant STS/Apollo platforms offer an alternative starting point
nor does it tell us if the propellant is PBAN or HTPB