Crewed version of Cygnus? I thought their proposal was the Prometheus spaceplane?
Since the primary payload for this concept would likely be commercial spacecraft, not people, it is possible for Orbital and Scaled to develop a single engine version of Antares with wings, using an RD-8 based upper stage, likewise constructed by Scaled. This would be able to loft some GEO comsats at a reasonable price.
I still wonder about the Antares part. If they use the Ukranians, They halve 3.9m tooling (Zenit-2/Antares) and the 3m tooling from the Cyclone family. Depending on the size, they could use either. The only issue is that the latest changes required tooling and structural changes that SpaceX wasn't willing to invest on. Could the Ukranians do it? Would they have the necessary experience?
Since the primary payload for this concept would likely be commercial spacecraft, ...
Quote from: Danderman on 11/28/2012 03:32 pmSince the primary payload for this concept would likely be commercial spacecraft, not people, it is possible for Orbital and Scaled to develop a single engine version of Antares with wings, using an RD-8 based upper stage, likewise constructed by Scaled. This would be able to loft some GEO comsats at a reasonable price.Why RD-8?
RD-8 is about the same thrust level as the RD-58 that Blok-DM uses. For GTO launches, the standard configuration is an upper stage much smaller than the first stage, but very long burning (see Atlas V/Centaur for comparison).The comparison gets a little blurry when considering that the airplane is really the first stage, but the desirement for a "small" upper stage still holds.
Quote from: baldusi on 11/28/2012 12:14 pmI still wonder about the Antares part. If they use the Ukranians, They halve 3.9m tooling (Zenit-2/Antares) and the 3m tooling from the Cyclone family. Depending on the size, they could use either. The only issue is that the latest changes required tooling and structural changes that SpaceX wasn't willing to invest on. Could the Ukranians do it? Would they have the necessary experience?I'm dubious they would. Scaled Composites was already going to build roughly half of the Falcon Air's first stage anyway, so it would make sense for them to step in and build the structure for the entire first stage. Everything else on Antares (engines, avionics, upper stage) would probably make the transition easily enough.
Quote from: simonbp on 11/28/2012 08:35 pmQuote from: baldusi on 11/28/2012 12:14 pmI still wonder about the Antares part. If they use the Ukranians, They halve 3.9m tooling (Zenit-2/Antares) and the 3m tooling from the Cyclone family. Depending on the size, they could use either. The only issue is that the latest changes required tooling and structural changes that SpaceX wasn't willing to invest on. Could the Ukranians do it? Would they have the necessary experience?I'm dubious they would. Scaled Composites was already going to build roughly half of the Falcon Air's first stage anyway, so it would make sense for them to step in and build the structure for the entire first stage. Everything else on Antares (engines, avionics, upper stage) would probably make the transition easily enough.Also, nobody had (yet) made composite main tanks for a LV. And I'm pretty sure they would like to start with something smaller, like the LauncherOne. Not only do they lack the material and experience of Yuzhnoye, but they don't have the tooling for the job. The Ukranians do, and, they did designed their stages to be air transported on the An-225. I can't really think of a better team than Yuzhnoye/Orbital to design an air dropped LV.
If we assume for a while that the LV will be have two stages dropped, and looking at the thrust of 4 to 5 Merlin 1D, I would assume that they expected a total weight of around 220tonnes to 280tonnes. If we assume an 8:1 relationship between first and second stage, they could use RL10, HM7B, Vinci or LE-5B for H2, RD-8/RD-809 or RD-0124 for RP-1/LOX and even the AJ-10 for hypergolics. And that's assuming that they don't get into some new player, like XCOR.
Not only do they lack the material and experience of Yuzhnoye, but they don't have the tooling for the job. The Ukranians do, and, they did designed their stages to be air transported on the An-225. I can't really think of a better team than Yuzhnoye/Orbital to design an air dropped LV.
And I'm sure it's a great powerpoint rocket. But Scaled does know a thing or two about actually building aeroplanes and air launched rockets. And once they finish the Birdzilla, they'll have plenty of space capacity...
Updated article posted elsewhere but not here for some reason:http://news.yahoo.com/orbital-sciences-replaces-spacex-stratolaunch-project-231138310.htmlThe addition of the "chine" kinda has me wondering how the flight profile is looking. Might be a "recovery" asset or it might simply be for additional lift for the aero-turn.Randy
Quote from: RanulfC on 12/05/2012 09:02 pmUpdated article posted elsewhere but not here for some reason:http://news.yahoo.com/orbital-sciences-replaces-spacex-stratolaunch-project-231138310.htmlThe addition of the "chine" kinda has me wondering how the flight profile is looking. Might be a "recovery" asset or it might simply be for additional lift for the aero-turn.RandyI think it reduces the horizontal stabilizer surface area. Think of it as an ascending lifting body. IMO if you use chines than you basically need a new airframe design to replace the usual cylindrical rocket airframe.