Quote from: John Alan on 08/13/2017 12:50 amStop thinking of rockets as machines that you tweek performance on at all costs and only fly with nearly a full payload...Not feasible. Too much interaction between payload and vehicle.
Stop thinking of rockets as machines that you tweek performance on at all costs and only fly with nearly a full payload...
Quote from: Jim on 08/13/2017 01:01 amQuote from: John Alan on 08/13/2017 12:50 amStop thinking of rockets as machines that you tweek performance on at all costs and only fly with nearly a full payload...Not feasible. Too much interaction between payload and vehicle.It's plenty feasible, it's just makes no business sense.
Quote from: Jim on 08/13/2017 01:01 amQuote from: John Alan on 08/13/2017 12:50 amStop thinking of rockets as machines that you tweek performance on at all costs and only fly with nearly a full payload...Not feasible. Too much interaction between payload and vehicle.It's plenty feasible, it's just makes no business sense. If a company really wanted to accept miscellaneous payloads at the last minute it could be done. They could do analysis, testing, and qualification over a huge range of payload properties. They could design payload adapters that help decouple the critical loads, using active compliance if needed.
Although I'm not sure about a full-size ITS, the CommX launch requirements could justify a launcher bigger than FH all by itself, should later iterations of the satellites get bigger to concentrate their bandwidth footprint. The obvious thing that is missing is a far bigger shroud for a much lower density payload. Big antennae are fluffy, even when folded.If constellations get popular, you could generalize a bit. You only need one customer per launch if that customer is attempting to fill most of an orbital ring in one launch. But I can only think of two possible CommX competitors, OneWeb and the Chinese, and they're obviously going to want their own launchers. I see a future of three constellations, one American, one European, and one Chinese, each trying to poach customers from the other's continents, each with one or more governments trying to put a thumb on the scale to make their favorite win more business.Of the three, the Chinese have the largest domestic market.
Bezos doesn't want to be encumbered like ULA is. Bezos doesn't need to compete even with SX, he could do "gradatim ferociter" indefinitely.
That said, a tenfold or hundredfold reduction in cost that Musk wants to see is really hard to accomplish, maybe impossible.
But Blue is positioning itself to learn all of SpaceX' lessons and build a launch system that is as efficient or more so than what SpaceX has.
One advantage of a greatly oversized booster for the job is that you could keep G-loads down.
Quote from: Nomadd on 08/13/2017 11:06 pm One advantage of a greatly oversized booster for the job is that you could keep G-loads down.unrelated to vehicle size
One advantage of a greatly oversized booster for the job is that you could keep G-loads down. That might make it a lot easier to certify the payloads for the booster. Not sure what you could do for vibration or the relationship between vibration and number/types/throttling of engines. But, if they could come up with a service that's significantly lower G loading and vibration intensity in all axes, maybe from a shock absorbing platform, any payload designed for multiple launchers should be happy. Lots of things will be easier and faster when they don't always have to chase that last 10 percent performance wise.
Quote from: Jim on 08/14/2017 12:31 amQuote from: Nomadd on 08/13/2017 11:06 pm One advantage of a greatly oversized booster for the job is that you could keep G-loads down.unrelated to vehicle sizeI think the implication was that excess performance could be spent on lower acceleration during ascent / higher gravity losses? Which would depend on vehicle max performance vs. payload size, not overall vehicle size.
And again we are wandering away from the near term competition discussion and into a tech discussion on a LV that is many years away.
Irrelevant. Comments in this thread try to take us back/forward decades. Clearly the two years is "immediate future" i.e. obvious direction.
There is nothing disruptive about Tesla and nothing disruptive (yet) about SpaceX.