SpaceX Conducts Full Thrust Firing of Falcon 9

Toren Altair sends us this excerpt: "Space Exploration Technologies Corp. (SpaceX) conducted the first nine engine firing of its Falcon 9 launch vehicle at its Texas Test Facility outside McGregor on July 31st. A second firing on August 1st completed a major NASA Commercial Orbital Transportation Services (COTS) milestone almost two months early. At full power, the nine engines consumed 3,200 lbs of fuel and liquid oxygen per second, and generated almost 850,000 pounds of force — four times the maximum thrust of a 747 aircraft. This marks the first firing of a Falcon 9 first stage with its full complement of nine Merlin 1C engines. Once a near term Merlin 1C fuel pump upgrade is complete, the sea level thrust will increase to 950,000 lbf, making Falcon 9 the most powerful single core vehicle in the United States. The Falcon 9 will launch SpaceX's spaceship Dragon with up to 7 humans from 2009 on." We discussed SpaceX when it won the NASA competition to provide low cost commercial transport to the ISS, and also when it launched an earlier design. Basic specs for Falcon 9 are available, as well as a more technical paper (PDF).

Re:So...only a year to go?

[AJWM]

Well no, because seven really is the upper limit. They just don't specify the lower limit.

And you don't need to use the operational launcher to test the lander, you can use something else. It's not like the Apollo program used a Saturn V (or even Saturn IB) to develop the Apollo capsule. For some of the drop tests they didn't use a rocket at all.

Re:Duh

[Anpheus]

They're talking about single point of failure. The space shuttle, for example, has a single point of failure: if either of the two engines fails, the whole thing fails. The result is that the overall reliability is the square of the reliability of the two engines. 99% reliable becomes 98.1% reliable. If it were the other way around, it would be the square root: 99.99% means it fails one in every thousand launches, as opposed to one in every fifty.

So what he's saying is, they can afford to have engines become nonfunctional (obviously not explosively so.) So even if each engine is only 80% reliable, if it only takes four to get to orbit, they can use nine, and get 99.9% reliability. If each engine is 99% reliable, you're talking way better than six sigma.