Saturn V To Mars?

Saturn V To Mars?: Among the kerosene-fueled rocket engines NASA is considering as a powerplant for its planned heavy-lift Space Launch System (SLS) is the venerable F-1 engine that took 12 men to the Moon.

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Pratt & Whitney Rocketdyne, which owns rights to the massive engines built by its predecessor Rocketdyne, proposed it as an option to companies that have submitted risk reduction proposals to the U.S. space agency for a strap-on SLS booster.

The advanced booster would crank the lift capacity of the deep-space SLS up to at least 130 metric tons, from the targeted 70 metric tons after its first scheduled flights in 2017 and 2021. It's early days yet, to say the least, but the engine-maker had interest in the big old engine from some of the launch vehicle companies that submitted proposals, so it's on the table for the time being.

Rocketdyne built F-1 and F-1A variants of the first stage engine for the Saturn V Moon rocket, at 1.5 and 1.8 million pounds thrust, respectively. PWR has several F-1 turbopumps in stock, and the five flight engines built for the cancelled Apollo 18 mission are still around.

NASA will decide this summer what design options for the advanced booster that it wants to pursue,  and the F-1 has some advantages. It's still the most powerful rocket engine ever built, and Rocketdyne engineers in the 1960s solved issues like combustion stability that  would cost a fortune to recreate today.

The modern company also proposed the Russian-built RD-180 that it supplies under license to power the Atlas V, and a developmental engine designated the RS-84. Started for NASA's terminated Space Launch Initiative, that staged-combustion kerosene-fueled  engine develops about  1.05 million pounds thrust, as does the RD-180, but it didn't draw the attention from the booster bidders that the completed engines did.

PWR is already upgrading the upper-stage engine from the Saturn V for the SLS upper stage. Known as the J-2X, it is undergoing  tests on two different test stands at Stennis Space Center. As it has done with the J-2X, the company says it would upgrade the F-1 with modern manufacturing techniques to hold down production cost.

Current plans call for PWR to finish the J-2X development, and then put it on hold until NASA is ready to begin flying  the upper stage, probably in the late 2020s. If the advanced booster is also flying then with an F-1 powerplant, the two Saturn engines' basic designs would be 60 years old.

But then, the basic design of the internal combustion engine for motor vehicles is older than that. Like automakers, rocket makers don't see the need to reinvent the wheel.