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PKIDelirium
Veteran Member
 
Join Date: Oct 2005
 
2020-07-01, 10:02

They lost a couple flown-several-times-already boosters on Starlink missions earlier in the year, but Starlink was a trajectory they weren't fully used to, and other factors played into both. One of them lost the center engine from some alcohol used in the between-flight cleaning process had been left in part of the system, and without the center engine you can't steer correctly or fire the landing burn. It burned up during entry. The other one had rough seas in the landing area and self-aborted to hit the ocean so the droneship wouldn't be damaged.

By default, the grid fins keep them on a trajectory to deliberately miss the droneship or ground pad until the landing burn starts, so if there's a problem, they just hit the ocean. When the landing burn starts (or fails to start for whatever reason), that's when the booster's guidance computer commits to either correct that and target the pad/ship, or abort into the drink.
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