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SpaceX Sends Dragon To ISS But Falcon 9 Rocket Misses Landing Pad (cnet.com)
On Wednesday, SpaceX successfully sent a Dragon spacecraft to the International Space Station to deliver supplies, but unfortunately it wasn't able to recover the Falcon 9 rocket that launched with it. "The first stage of the Falcon 9 launch vehicle appeared to lose control as it approached Landing Zone 1 at Cape Canaveral," reports CNET. "The live feed from the rocket cut away on the SpaceX webcast, but video from people in the media area at the cape showed the Falcon 9 appearing to regain control before making an unplanned landing in the water rather than ashore at the landing area." From the report: Musk tweeted shortly afterward that cutting the live feed "was a mistake" and shared the full clip of the water landing from the rocket's perspective. The rocket took off from Kennedy Space Center in Florida at 1:16 p.m. local time, a little more than 48 hours after SpaceX sent another Falcon 9 to space from the West Coast on Monday. Dragon's flight to low-Earth orbit was supposed to happen Tuesday, but the mission was pushed back a day to replace some food being sent to the space station for experimental mice living there.
SpaceX had planned to land the first stage of the brand-new Block 5 Falcon 9 rocket at a landing zone ashore at Cape Canaveral, but as the rocket descended toward the cape, the live feed from the booster's onboard cameras appeared to show the craft going into some sort of uncontrolled spin. Musk tweeted that the problem was that a "grid fin hydraulic pump stalled, so Falcon landed just out to sea." Musk also tweeted that the pump that failed didn't have a backup because "landing is considered ground safety critical, but not mission critical. Given this event, we will likely add a backup pump & lines."
SpaceX had planned to land the first stage of the brand-new Block 5 Falcon 9 rocket at a landing zone ashore at Cape Canaveral, but as the rocket descended toward the cape, the live feed from the booster's onboard cameras appeared to show the craft going into some sort of uncontrolled spin. Musk tweeted that the problem was that a "grid fin hydraulic pump stalled, so Falcon landed just out to sea." Musk also tweeted that the pump that failed didn't have a backup because "landing is considered ground safety critical, but not mission critical. Given this event, we will likely add a backup pump & lines."
The more impressive thing is that it managed to splash down intact, under full control. Due to the stuck hydraulics for the grid fins, it was rolling at a fairly extreme rate. The rocket had already aimed at this spot in the water (it's designed this way) and was actually able to arrest the roll just prior to splash down. After splash down, it remained operational, despite falling onto its side, and successfully safe itself. Apparently it was still in communications and operational while bobbing away in the ocean.
For the uninitiated, the landing profile has the initial trajectory set with the booster aimed for a region away from the landing pad, be it the one on the ground, or the barge. This is in case of exactly a situation such as this, if something goes wrong during the landing process and the booster loses control authority, it will impact somewhere safe. It's only during the final landing burn (aka the hoverslam) that the booster side slips and changes its trajectory to land in the landing zone.
So yeah, the system worked exactly as designed, and is fail safe. All in all a successful failure.
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