Seems like a better solution would be 9 BE-3's on first stage, with one BE-3 vacuum for second stage. All hydrolox, all the same engine, and reusable like the Falcon 9, it would be the Delta 9.
How about 7 BE-4 engines on a 7M diameter first stage? Reusable of course, a Vac optimized BE-4 on the second and a BE-3 third stage for when you need that extra ommph for deep space missions?
Quote from: M_Puckett on 05/18/2017 03:14 amHow about 7 BE-4 engines on a 7M diameter first stage? Reusable of course, a Vac optimized BE-4 on the second and a BE-3 third stage for when you need that extra ommph for deep space missions?About New Glenn as name.
We do not have the payloads to justify the SLS. It is obsolete in the sense that none of it is reusable; and wasteful in the sense that it throws away the most expensive portion that actually was intended to be re-used - the RS-25D. It has already cost way too much. Cancel SLS.Since it was pointed out to me that a restartable RS-25 would mean a drastic redesign, I was at a loss how to get them back for reuse. Then it dawned on me that the new BE-3 is restartable, and it exists today. So:Epsilon.Put out a new contract to build a bigger Hydrolox rocket. In my mind ULA would build and manage this vehicle. It would not be so big that the other launch providers cannot compete for payloads. Keep NASA (yes I know it's Boeing) out of the booster building business and get them building payloads.Epsilon would use the 27.5 ft tank tooling at Michoud, but shrink it back to a capacity more similar to the Shuttle ET. Big enough to run the following for the same 2.4 minutes that has become the sweetspot for booster return: 6 RS-25D's, surrounding 10 BE-3's.
Quote from: robert_d on 05/18/2017 02:11 amWe do not have the payloads to justify the SLS. It is obsolete in the sense that none of it is reusable; and wasteful in the sense that it throws away the most expensive portion that actually was intended to be re-used - the RS-25D. It has already cost way too much. Cancel SLS.Since it was pointed out to me that a restartable RS-25 would mean a drastic redesign, I was at a loss how to get them back for reuse. Then it dawned on me that the new BE-3 is restartable, and it exists today. So:Epsilon.Put out a new contract to build a bigger Hydrolox rocket. In my mind ULA would build and manage this vehicle. It would not be so big that the other launch providers cannot compete for payloads. Keep NASA (yes I know it's Boeing) out of the booster building business and get them building payloads.Epsilon would use the 27.5 ft tank tooling at Michoud, but shrink it back to a capacity more similar to the Shuttle ET. Big enough to run the following for the same 2.4 minutes that has become the sweetspot for booster return: 6 RS-25D's, surrounding 10 BE-3's.If you propose to put out a contract to build a LV, why do you specify its design? You should specify what performance and price you require.
Quote from: spacenut on 05/18/2017 02:26 amSeems like a better solution would be 9 BE-3's on first stage, with one BE-3 vacuum for second stage. All hydrolox, all the same engine, and reusable like the Falcon 9, it would be the Delta 9. Not big enough. Not in this HLV section anyway. Looking for something bigger than is flying now, but reusable. Big enough hopefully to get Orion up to LEO with margin. I had another post proposing using 2 RS-25 plus 3 BE-3's (for boostback) as my human rated Hydrolox EELV class vehicle.
If you propose to put out a contract to build a LV, why do you specify its design? You should specify what performance and price you require.
Quote from: gospacex on 05/18/2017 06:13 amIf you propose to put out a contract to build a LV, why do you specify its design? You should specify what performance and price you require.Exactly. Specifiying what hardware it should use is the same mistake the US Senate made with SLS. It did not get the alternative name "Senate Launch System" for nothing.
A project is lost when requirements dictate the design.
But I don't think a shuttle derived vehicle without the solid is politically viable.
Quote from: woods170 on 05/18/2017 12:12 pmQuote from: gospacex on 05/18/2017 06:13 amIf you propose to put out a contract to build a LV, why do you specify its design? You should specify what performance and price you require.Exactly. Specifiying what hardware it should use is the same mistake the US Senate made with SLS. It did not get the alternative name "Senate Launch System" for nothing.A project is lost when requirements dictate the design.Apollo had a very simple top-level requirement: put a man on the Moon. Not to make Saturn V.That is what is missing for NASA: one or two top level requirements. The rest is engineering and budget.