Laboratory planner by day, toddler parent by night, enthusiastic everything-hobbyist in the thirty minutes a day I get to myself.

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Cake day: July 31st, 2023

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  • Hydraulics and electric system are independent in commercial aircraft – hydraulic pumps are directly driven from the engines, as are electrical generators. Redundancy is provided via independent loops/buses from each engine. A bird strike on its own is unlikely to be energetic enough to sever one of those independent systems, let alone all four. Losing both engines could do it, – but again, they had enough thrust to attempt a go-around, so they weren’t a glider immediately after the bird strike. The 737 is an old-school design, too, so most critical components have full manual reversion – as long as you have airspeed and altitude enough to get to the runway, you can fly and land the plane just with cable controls and manual releases in the event of total electric and hydraulic failure.

    I did a bit of reading from other sources and this particular aircraft predates the requirement for battery backup of the FDR and CVR, and the APU does not start up automatically on a power failure, so the failure chain for that part of the incident isn’t as long as I initially thought. Still, lots of questions, and I think the simplest explanation so far is the aircrew panicking and making a survivable situation into a bloodbath.


  • Everything about this incident is just so fucking odd. That a bird strike could take out both engines isn’t unheard of (see US Airways Flight 1549) but I’ve heard reports that there was a failed emergency landing attempt before the one that we saw video of, so they clearly had thrust enough to stay in the air for a go-around, and from the video we saw they carried in a ton more speed than I would expect if there had been catastrophic damage to both engines.

    Except that the lack of landing gear suggests loss of hydraulic power from both engines… Except there is an emergency release that drops the gear on a 737 with just gravity, and there’s no evidence this was even attempted.

    Now it looks like some electrical systems, including power to the data recorders, died right at the start of the incident, which would require not just double engine failure but failure of the APU and backup battery systems. That just seems incredibly unlikely.

    Catastrophic electrical failure several minutes before the crash, though, would suggest that it wasn’t just a case of a panicked aircrew making a chain of bad decisions, which was my initial read of the situation and maybe the best fit for the rest of the circumstances.

    I just can’t think of a chain of events that could reasonably lead to all the failures in evidence while still allowing the aircraft to remain airworthy for two landing attempts.

    And then you get to the horrifying fact that a relatively new and modern airport had a giant concrete obstacle in what would be considered the Runway Safety Area at a US facility… Like, what the fuck? That seems like it’s designed to create this sort of a disaster.