Quote from: llanitedave on 01/07/2015 03:59 pmYou'd get some awful drag losses for the first stage with that kind of design.it's not an "optimal" design. It's a stepping stone to their final LV that wouldn't require the tangential investment of a new diameter LV, with it's tooling, logistics, etc. But, it certainly would be powerful enough to overcome the additional drag, and it would be reusable so the only actual hit is a little extra fuel. So would it be an issue, really?Might look something like Little Joe, less the LAS and fins. Heheh.
You'd get some awful drag losses for the first stage with that kind of design.
Quote from: Robotbeat on 01/06/2015 11:46 pmit'd also cement SpaceX's domination of the launch industry. (BFR would leave an opening for a better-optimized RLV which could still compete in the high-revenue Ariane5/Proton market.)Let's see. What is SpaceX goal? Two options:1 - Sufocate all the competition, inviabilizing the development of any new comercial launch vehicle, and become a monopolist in word-wide non-governamental launches.2 - Advance the state of the aerospace technology, and enable large scale Mars colonization.I guess it is the second one, so I don't think that was a good argument.
it'd also cement SpaceX's domination of the launch industry. (BFR would leave an opening for a better-optimized RLV which could still compete in the high-revenue Ariane5/Proton market.)
So if 24 raptors is 39's limit, and President Shotwell said the pad's far to small for BFR, it's fair to suspect more than 24 raptors on the BFR first stage.
They dont need to equal the capasity of Falcon Heavy, there are no payloads that need anything close to the the full capasity of Falcon heavy.Even with only 5 engines it could lift _any_ commercial or goverment satellite and still be fully reusable.Though second stage with one raptor would then be way overpowered, but making second stage big and staging early might make reuse of first stage easier/more efficient.
Quote from: Lobo on 01/07/2015 04:07 pmQuote from: llanitedave on 01/07/2015 03:59 pmYou'd get some awful drag losses for the first stage with that kind of design.it's not an "optimal" design. It's a stepping stone to their final LV that wouldn't require the tangential investment of a new diameter LV, with it's tooling, logistics, etc. But, it certainly would be powerful enough to overcome the additional drag, and it would be reusable so the only actual hit is a little extra fuel. So would it be an issue, really?Might look something like Little Joe, less the LAS and fins. Heheh.Little Joe was suborbital, so that example undercuts your point. It kind of indicates that you can't actually find an orbital launcher that was short and fat.
Taking as much market share as possible is not the same as being a monopolist.Musk has always done everything he can to get as much market share as possible. That is necessary to fund Mars colonization.
At some point SpaceX is going to need to develop an upper stage engine.
Quote from: wannamoonbase on 01/08/2015 02:50 amAt some point SpaceX is going to need to develop an upper stage engine.SpaceX has developed a dedicated upper stage engine in the past, Kestrel.
What's the maximum number of engines that the SFR might cluster and still be able to land on a single central engine?Could one have a 13 raptor engine cluster?
Well, to be fair to Lobo, one could also say that the Space Shuttle stack was aerodynamically suboptimal as well, definitely short and fat compared to some other vehicles.