SpaceX finally launched the Intelsat 35e telecommunications satellite today atop a Falcon 9 rocket after two earlier attempts were aborted at T-minus-9 seconds.
Those two attempts, on Sunday and Monday, were called off by SpaceX’s computer system when the parameters it had didn’t match up with what it expected. But when the engineers checked, it turned out there was nothing wrong with the rocket.
The computer’s go/no-go parameters were tweaked to be more forgiving, SpaceX launch commentator John Insprucker said today.
This time, the countdown ticked past the 9-second mark and the Falcon 9 rose smoothly from Launch Complex 39A at NASA’s Kennedy Space Center in Florida at 7:38 p.m. ET (4:38 p.m. PT).
Intelsat 35e is the fourth of the Intelsat Epic next-generation high-throughput satellites. It’s designed to provide video and broadband data services via the C-band and Ku-band parts of the spectrum.
The satellite weighs nearly 15,000 pounds and is designed for geostationary orbit, more than 22,000 miles above Earth’s surface. It’s the heaviest satellite SpaceX has ever put in so high an orbit.
Because of the satellite’s weight and intended orbit, the two-stage Falcon 9 needed all the fuel it could muster. That meant there wouldn’t be enough left over to land the first-stage booster after ascent, as has become nearly routine. This time around, SpaceX didn’t even bother installing landing legs.
SpaceX’s billionaire founder, Elon Musk, said the Falcon 9 significantly surpassed the minimum requirements for getting Intelsat 35e into orbit:
Thanks @INTELSAT! Really proud of the rocket and SpaceX team today. Min apogee requirement was 28,000 km, Falcon 9 achieved 43,000 km.
— Elon Musk (@elonmusk) July 6, 2017
Today’s launch was the third Falcon 9 launch in less than two weeks. The two previous missions involved landings as well as launches: On June 23, a previously flown Falcon booster helped put the BulgariaSat-1 satellite into orbit, and touched down on an oceangoing platform in the Atlantic. Then, on June 25, a brand-new Falcon sent 10 Iridium NEXT satellites to orbit, with a booster landing as the capper.
Frequent launches and the reuse of rocket hardware are part of SpaceX’s strategy for reducing the cost of access to orbit, and eventually making spaceflight inexpensive enough to turn Musk’s vision of sending settlers to Mars into reality.
In March, Musk told reporters that he is aiming to cut the turnaround time between rocket launches to 24 hours by next year.