alt Hacker News> There was no indication in the recorded data that speed brakes or thrust reversers were deployed.
I don't know anything about flying. Is this normal? Doesn't sound like it, but I don't know why the pilots would not have used these things that sound useful.
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Take this with all the salt that random third-party guesses about a still-in-investigation event should be taken with -- think fully salt-cured ham -- but it looks like the landing was with a quartering tail wind, and the upwind (left) gear never really got weight on it; the wheel bogie needs to be straightened by weight against both the front and back wheels to register weight-on-wheel, and the auto-brake systems need positive weight-on-wheels from at least one redundant sensor on each of the three gear to engage. Came down hot, and basically skimmed with one wheel partially off the ground for some, most, or all of the way down the runway, preventing the braking systems from kicking in.
Someone who flew this exact airframe wrote that this plane "likes to float when empty, so if you’re not firm with putting it down, especially with those winds, it’ll just keep floating in ground effect."
https://www.reddit.com/r/aviation/comments/1w9jsrb/put_toget...
I'm not a pilot but from my understanding there's a lot of failsafes to ensure things that slow the plane down only trigger when the plane is actually on the ground. Considering that the left gear touched down at 0:19 and pilot called for TOGA at 0:15 they didn't stand a chance.
> I don't know anything about flying. Is this normal?
Not deploying thrust reversers is normal, not all situations require them. But brakes are terrible when the wings are still flying, so spoilers (if armed as they should) automatically deploy when all wheel sensors report the aircraft is on the ground, so that there will be more weight on the wheels and the brakes can work properly.
Depending on the plane they need the wheels to have sufficient weight on them first. Also strangely the flaps 30 and flaps 40 call outs do not match.
The lack of contact of the left wheels on the ground, which the Weight of Wheel sensor deployment depends on, as in both wheels being grounded, which the auto-speed brakes/thrust reversers depend on, worsened the whole situation as the crew seems to be unaware why they weren't losing speed after they'd 'landed'.
Every single thing they could do wrong at, they did.