A week spent reviewing data has confirmed that the flight went really well, including the coast and restart. The mood here at SpaceX is just ecstatic! This is the culmination of six years of hard work by a very talented team. It is also a great relief for me, who led the overall design of the rocket (not a role I expected to have when starting the company). I felt a little sheepish receiving the AIAA award for the most outstanding contribution to the field of space transportation two weeks before this flight.
Orbit was achieved with the first burn terminating at 330.5 km altitude and 8.99 degree inclination. The goal for initial insertion was a 330 km altitude and a 9.0 degree inclination, so this was right on target! Accuracy far exceeded our expectations, particularly given that this was the first time Falcon 1 reached orbit.
The primary purpose of the second burn was to test the restart capability and then burn as long as possible. The upper stage coasted for 43.5 minutes and then burned for 6.8 seconds, which is 4 seconds longer than needed to circularize. Most of the burn was actually done sideways to avoid creating a highly elliptical orbit, hence a change in inclination to 9.3 degrees. The final orbit, confirmed by US Space Command, was 621 km by 643 km.
As an added bonus, we picked up several minutes of video and data from the upper stage when it passed over Kwajalein one orbit later, which showed the stage to be in good condition. You will see some eerie footage of the upper stage drifting in zero g at the end of the video clip below.
After one complete orbit, the SpaceX Falcon 1 Flight 4 vehicle passes over its launch site at the Kwajalein Atoll, and returns a view of the Earth.
While Falcon 1 was the world’s first privately developed liquid fuel rocket to reach orbit, I would like to acknowledge and express appreciation for the role of DARPA, the Air Force and the ORS Office of the Department of Defense. They played an important role as early “beta” customers of Falcon 1. There are many individuals in those organizations, as well as in NASA, NRL, FAA, USAKA/RTS, other departments of the US government and the private sector to whom we owe gratitude for their support and advice. You didn’t have to help, but you did, often at risk of career and credibility, so you have my deepest thanks.
The next flight of Falcon 1 is tentatively scheduled for March next year and will carry a Malaysian primary satellite, as well as US government secondary satellites, to near equatorial orbit. Flight 6 will probably be a Defense Department satellite in the summer and Flight 7 a commercial satellite mission in the fall. In 2010, I expect the launch cadence for Falcon 1 to step up to a mission every two to three months.
Below is a highlight reel of the Falcon 1 flight, including the restart and video footage from the upper stage when it does its first orbit back over Kwajalein. Some of this has not been show before, so there is something new even if you watched the live webcast.
–Elon–
Click the image below to view the highlight reel from the SpaceX Video Gallery:
Liftoff of Falcon 1, Flight 4 from the Kwajalein Atoll on September 28, 2008 (UTC).
