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NASA Considers Apollo-Era F1 Engine For Space Launch System
MarkWhittington writes "A company named Dynetics, in partnership with Pratt & Whitney Rocketdyne, will perform a study contract for NASA to explore whether a modern version of the Saturn V F1 booster (PDF) could be used on the Space Launch System. These would be the basis for a liquid fueled rocket that would enhance the SLS to make it capable of launching 130 metric tons to low Earth orbit, thus making it capable of supporting deep space exploration missions in the 2020s."
I would LOVE to see the F1 back in action. Few things have inspired such awe in me as the launch of a Saturn V rocket and the five tremendous columns of fire atop which it strode.
"Tell me doctor, with all of your defenses, are there any provisions for an attack by killer bees?"
The F1 is a perfect example of a big dumb booster. It is cheap, especially so if you mass produce it. The Space Shuttle Main Engines are examples of non-stone age rocket design that uses advanced materials and tries to be reusable. Guess which one is cheaper to operate?
Here's a hint: the Russians like big dumb boosters for a reason.
Because it is good engineering practice to know what has been done before? We do not build things in a vacuum, but rather we build upon the successes and failures of others. By knowing what has failed in the past we can avoid those traps in the future and by knowing what has worked we can have a firm foundation upon which to improve.
Yeahbut....we wouldn't be basing the new F-1 type engine on the original F-1, we'd be using the F-1A.
The F-1A has 33 percent more thrust than the F-1.
9,189.60 kN for the F-1A versus 7,887 kN for the RD-171
But here is where the real difference comes in:
Lox/RP-1. Thrust to Weight Ratio: 115.71. for the F-1A
It's 82 for your Russian motor. Thus the advantage of using one combustion chamber compared to using 4.
Modern materials should lighten the F-1A and modern controls should improve efficiency and thrust even more to improve the thrust to weight ratio.
Why the Russians never use large combustion chambers and why you see 4 of them on the RD-171: They never solved the problem of combustion instability beyond a certain size. We did.
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BMO
Saturn V wasn't used to boost large payloads to LEO
On a lunar mission, the Saturn V would put the Command and Service Module, the Lunar Module, and a booster with enough fuel to put them both on a lunar trajectory, into LEO. That's a pretty damn large payload, the largest payload to LEO of any single vehicle ever produced. The fact that the payload eventually boosted itself the rest of the way to the moon isn't relevant to the vehicle's ability to put mass into LEO.
It is the nature of rocketry that any small mass in a high orbit will tend to get there by going through a period in which it is a large mass in a lower orbit. In a staged rocket, it is useful to think of each stage as its own vehicle, with all of the stages above it as its payload which it is capable of delivering to a certain point.
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