So, if they replace 9 Merlin 1's with 1 Merlin 2 it wouldn't be called a Falcon 9 anymore correct?
Quote from: Aeroman on 02/23/2011 05:28 pmSo, if they replace 9 Merlin 1's with 1 Merlin 2 it wouldn't be called a Falcon 9 anymore correct?As 'Falcon-1' is already taken, I imagine that they would have to carry on calling it Falcon-9. They'll probably give it a variant designation like 'Falcon-9a' or something.
Please remember that one of the things that they changed from Merlin 1A(or B) to C was that they made their own turbopump.
How scalable are turbopump designs? I think very easy downscale (Rd-171 -> RD-180 -> RD-191), but very difficult upscale.
Elon already mentioned that they were looking at a cross-fed solution for multiple cores. I believe that was in the interview just after the second F9 launch.Assuming he means this for Falcon 9 Heavy, then there's no need to throttle down or leave out engines.Also keep in mind that Falcon 9 Heavy will probably be migrating from 27 Merlin 1s to 3 Merlin 2s.
Quote from: baldusi on 02/23/2011 07:27 pmPlease remember that one of the things that they changed from Merlin 1A(or B) to C was that they made their own turbopump. They have yet to do that
Quote from: baldusi on 02/23/2011 07:27 pmHow scalable are turbopump designs? I think very easy downscale (Rd-171 -> RD-180 -> RD-191), but very difficult upscale.Hmm, my impression was always that turbo-machinery likes to be big, but I wouldn't swear by that.AFAIK the (relative) ease of developing the RD-180 was due to the difficult problems of the engine development (oxygen rich, high pressure etc..) being already solved, and the ability to re-use the combustion chamber / nozzle designs with very little change.
Cross-feed seems to take it up to ... about a 20% performance boost.Suggests it would provide a neat boost to performance of F9H, although not sure what payload might need that.
By the way what's up with their website? They really need better website management.
I just simply don't see SpaceX developing the Merlin 2 without a big commitment from the government, such as a HLV contract.
And don't forget that Merlin 2 can be used on Falcon 9 to reduce cost and increase payload capacity, again helping SpaceX commercially.
Quote from: Dave G on 02/24/2011 01:16 pmAnd don't forget that Merlin 2 can be used on Falcon 9 to reduce cost and increase payload capacity, again helping SpaceX commercially.Are you sure about that? IIRC, Merlin 2 would cost $50M, which is the price of one Falcon 9. For F9H, this seems even worse..
In my mind, it's obvious that one engine will have less recurring cost than 9 smaller ones.
SpaceX is not going to have that kind of money to spend on Merlin 2. Unless you're suggesting SpaceX will take the long approach and shoot to have it ready by like 2025.
Quote from: Nate_Trost on 02/24/2011 01:57 pmSpaceX is not going to have that kind of money to spend on Merlin 2. Unless you're suggesting SpaceX will take the long approach and shoot to have it ready by like 2025.If SpaceX has to develop Merlin 2 on their own, it may take 5-15 years, depending on how much money they get from the IPO and other commercial business. So 2025 is not out of the question.If NASA uses a public/private partnership with SpaceX to develop the HLV, then Merlin 2 will obviously happen much sooner.Either way, SpaceX will develop Merlin 2.
OK, how big part of Merlin 2 price quote is the result of "NASA would want SpaceX to do it in a hurry"?Or from an other viewpoint, how much would developing M2 cost for SpaceX, if it is on a "slow but steady" development path?