On 2020-01-20 3:28, Jeff Findley wrote:

Still, [the Falcon 9 first stage] looks to have been torn apart by
aerodynamic forces. The second stage was intact when it hit the ocean
(and created quite the fireball).
Interesting that the interstage seems to have stuck with the second
stage and not with the first stage, or so the videos of the falling
second stage seem to show.

The connection between the interstage and the second stage, which is
where the stages normally separate, seems to have been tougher than the
join between first stage and interstage, which is meant to be permanent.

There seemed to be a bulge at the lower end of the interstage, which
perhaps was the top bulkhead of the top propellant tank of the first
stage. So perhaps the split was the bulkhead coming loose from the tank
walls -- corresponding to the seam that failed in the recent Starship
"Bopper" test.

--
Niklas Holsti
Tidorum Ltd
niklas holsti tidorum fi
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