12 June 2010

Ares 1-X vs Falcon 9: A Comparison

Posted by Ryan Anderson

Well, I’ve been a bad space blogger, and didn’t write anything about the spectacular successful launch of  SpaceX Falcon 9 rocket on June 4th. Considering the ongoing wailing and gnashing of teeth over the cancellation of Constellation in favor of using commercial rockets to send astronauts to the ISS, I thought it would be worth taking a look at how Falcon 9 compares with the Ares 1-X, which launched back in October. Both rockets were launched as test flights, and the final design of both was meant to send astronauts and small amounts of cargo to and from the space station.

Ares 1-X was a suborbital test flight, using the same solid rocket booster that the finished Ares 1 would have used, but with the fifth segment of the booster, the second stage, the crew module and the escape tower as mass simulators rather than the actual components which were not ready at the time of launch. Ares 1-X also borrowed its avionics package from a commercial Atlas V rocket. Falcon 9 was an orbital flight, using a completed launch vehicle but a Dragon mass simulator “qualification unit” (see comment below).

The Ares 1-X rocket reached an altitude of 46 kilometers and traveled about 240 km downrange. When the upper stage simulator separated from the booster, it began to tumble. The real Ares 1 would have had boosters on the upper stage that might have been able to correct for the spin. One of the three parachutes on the Ares1-X booster failed, causing the booster to crash into the ocean harder than expected.

Falcon 9 launched successfully and reached its expected 250 km low Earth orbit. The spacecraft rolled more than expected late in the flight, and the theoretically reusable first stage broke up in the atmosphere, due to parachute failure.

The final Ares 1 would have been able to launch a payload of 25,400 kg into low Earth orbit. The constellation program called for the development of a heavy-lift vehicle, the Ares V, but no prototypes of that rocket have been built or tested. With the impending cancellation of Constellation, there are no more Ares test flights scheduled.

Falcon 9 can launch 10,450 kg into low Earth orbit, and a Falcon 9 “Heavy” variant, which would use two additional first stages as side-mounted boosters, would be able to lift 32,000 kg to LEO. The heavy variant has not been tested. A second Falcon 9 test flight, with a fully operational Dragon capsule is slated for later this summer.

The Ares 1-X project cost a total of ~$445 million, and the Augustine commission found that it would likely cost $5 to $6 billion to develop the final Ares 1 rocket. They predicted a recurring cost of about $1 billion per flight of the Ares 1/Orion launcher and spacecraft.

I can’t find a number for the project cost of the Falcon 9 development and launch, but a SpaceX press release (which I admit is not the most neutral source…) said:

For less than the cost of the Ares I mobile service tower, SpaceX has developed all the flight hardware for the Falcon 9 orbital rocket, Dragon spacecraft, as well as three launch sites.

Per-launch cost for the Falcon 9 is predicted to be around $50 million for the normal booster and $78 million for the Falcon 9 Heavy.

So what does the successful Falcon 9 launch mean for the future of spaceflight? It’s too early to really tell, but SpaceX had a major victory with its successful launch. Falcon 9 is a fully operational vehicle that had a nearly flawless test flight. Later this summer, we will hopefully see a second successful launch, including an operational Dragon capsule. And I don’t know about you, but my jaw just about hit the floor when I saw the cost of Ares 1 alongside the cost for Falcon 9.

To put it in perspective, if the Augustine commission estimate of $1 billion per Ares 1 flight is correct, and if the SpaceX estimates for the Falcon 9 launch costs are correct, you could launch about twenty Falcon 9’s or twelve Falcon 9 heavies for the same price as one Ares 1 launch. Converting that to payload to orbit, $1 billion could get you 209,000 kg to LEO using Falcon 9’s, 410,000 kg using Falcon 9 heavies, or 25,400 kg on the Ares 1.

There have been some negative comments saying that SpaceX just proved that it can do what NASA did fifty years ago, namely launch cargo into LEO. But those comments ignore the fact that once the shuttle is retired, NASA can’t do that anymore, and wouldn’t be able to for many years and many billions of dollars. The way things are going, it looks likely that SpaceX or another commercial provider will be able to fill the gap in access to the ISS much quicker and for much less money than if NASA were to do it.

In any case, I will leave you with videos of both the Ares 1-X and the Falcon 9 launches. Both spectacular and beautiful: