This one isn’t as speculative, anonymously sourced, or even controversial, just interesting.
Clark linked to an interesting article in Flight International about SpaceX’s plans for the Falcon 9. After mentioning the two heavy versions (ie the ones with strapons), they stated that:
However, development work for these will not start until a customer places an order.
“There is not a great amount of further development to be done [for the heavy versions],†says SpaceX chairman and chief executive Elon Musk. “We won’t spend that money until we have a customer. Then we will do aerodynamic analysis, separation systems, a few things like that.â€
He adds that development of the medium versions would include the attachment points for the heavy’s two strap-on stages and the analysis for the loading expected for heavy Falcon 9s.
Seems like a rather intelligent way of going about it. That way if nobody really wants that capability, SpaceX doesn’t have to waste money providing it, but if someone does, it can become quickly and readily available. If they get the three main Falcon designs (1, 5, and 9) flying reliably, and have done all the structural design work to make a Falcon 9 core, the amount of remaining technical risk for the Falcon 9 S5 or S9 is pretty minimal. Small enough that the risk of being the first customer isn’t that bad. Not only that, but SpaceX probably won’t even charge a premium for that development work–probably just the launch price.
The further mention that:
SpaceX will conduct a hold-down fire test of the Falcon 9’s first stage in the second quarter of 2006 and a fairing separation test in the fourth quarter.
SpaceX bought a 3Mlbf vertical test stand (the thing looks like a ten-story tall milk stool) from Beal Aerospace down near their other test facilities, and they could probably do a full duration test with all 27 engines. There are some weird aerodynamic effects that could happen due to the large number of engines interacting that couldn’t be effectively tested on the ground, but a full duration ground firing with all 27 engines lit could go a long way toward proving the reliability of the F9 S9 vehicle.
Jonathan Goff
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Why the figure of 27 engines for the Falcon 9-S9? Shouldn’t that be 81?
27=9×3
The base Falcon 9 has 9 Merlin mark 1 engines under it’s first stage.
The Falcon 9-S9 seems to have a Falcon 9 core, surrounded by 8 strap on falcon 9 first stage boosters.
81-9×9
should be “81=9×9” above.
Oh, I see. “9-S5” uses two extra falcon 5 first stages and “9-S9” uses two Falcon 9 first stages on the side.
Not as much fun…
Are you sure? Why would 8 engines and some fuel cost an extra $27 million?
Jsuros,
Are you sure? Why would 8 engines and some fuel cost an extra $27 million?
You’re confusing cost and price. Sure it may only cost SpaceX another $5M or so to do the launch, but they won’t be doing a bunch of them, and they need to recoup the extra development costs.
Or maybe they might just be trying to make a profit. Silly capitalists. 😉
~Jon
Adding two more booster coes to the sides of your rocket seems like a simple idea on the surface. In practice, it creates some problems that are hard to spot. Case in point: Delta IV Heavy. Who’d have forseen the cavitation problems that developed in the strap-on CBC’s?
Hopefully Delta IV’s woes will help SpaceX to be more alert to this seemingly-minute problems when they build the S5 and S9 variants of Falcon IX.
I stil wonder why how it all is supposed to be so much cheaper than the other companies.
Proabally because Mr. Musk has apparently designed for operational effiency first and performance second.
The big guys tend to do the opposite.