The first launch of SpaceX’s Falcon Heavy rocket last week was a smashing success, but not everything went perfectly. While SpaceX was able to recover two of the three first stage boosters, the center core failed to land on the drone ship. CEO Elon Musk has provided a bit more insight on what went wrong with that part of the flight. It turns out to be a fairly simple fix.
The Falcon Heavy is composed of three Falcon 9 boosters. The side boosters used in the Falcon Heavy launch were previously flown and recovered. Several minutes after liftoff, they split off from the core and made their way back down to Cape Canaveral. In a truly stunning display of precision, the pair of rockets landed at LZ-1 and LZ-2 near launch complex 39-A at almost the same moment. Musk says these boosters won’t be flown again.
SpaceX ended its live broadcast on launch day without providing an update on the fate of the center core. That one disconnected from the second stage (complete with Tesla Roadster) a few minutes after the side boosters dropped off. The core was structurally reinforced to accommodate the side boosters, but it was otherwise a standard Falcon 9. The plan was for the core to execute three engine burns to fly down to the company’s drone ship for an ocean landing. SpaceX has successfully landed multiple Falcon 9 rockets on the ship in the past.
We learned several hours after the launch that the center core had indeed crashed, but only now do we have an explanation. According to Musk, the core didn’t have enough ignition fluid to light the two outer engines of the booster for its final approach to the ship. As a result, the rocket crashed into the sea about 328 feet from the ship going over 300 miles per hour.
Landing the center core was always going to be a greater challenge than the side boosters. It was going faster, and it reached a higher altitude before disconnecting from the second stage. In future launches, the center core just needs more ignition fluid to ensure it can relight its engines before landing.
SpaceX is confident it can keep recovering boosters from Falcon Heavy launches. It’s in the process of building a third drone ship, which will be its second on the east coast of the US. That will allow it to conduct dual ocean landings for the side boosters.