At 0129 GMT on 22 December 2015 a SpaceX Falcon 9FT (Full Thrust) launch vehicle took off from the Cape Canaveral launch site in Florida. Aboard the rocket was a payload of Orbcomm commercial communications satellites, which was the first live launch since a launch failure earlier this year. However, their safe delivery using a second firing of the upper stage, did not steal the headlines. It was rather that after the first stage’s separation at a velocity of Mach 6 and at an altitude of 80km, the stage reversed course to blast its way back to Cape Canaveral. This reusable first stage was to attempt a landing at a disused pad location 10km away from the original launch pad. Using grid fins to control its attitude during its atmospheric passage at hypersonic speed, the Falcon 9FT reignited its central engine to decelerate itself to achieve a powered landing.
About nine minutes after lift-off the glowing centre engine could be seen over Florida as the rocket stage came down in a controlled descent, just as its sonic boom caught up with it. It landed successfully – this time not toppling over as it had done on previous mission attempts at landing on a barge at sea.
Comment by David Todd: Congratulations to the SpaceX team. This flight is the first step on what SpaceX leader Elon Musk believes will allow reusable technology to significantly reduce launch costs. This advance could effectively make most expendable rockets redundant if the economics of integration and assembly can be got right and a high flight rate maintained.
