It will be interesting to find out if they mean that the cvr stopped recording, meaning it stopped adding data to the file. Or if it stopped recording more like the incoming data lines were cut.
I just don’t see catastrophic failure. How big were those birds? I’m going to hold any more comments till we see CVR FDR tapes are released if ever. So strange.
We have the following observations to support catastrophic failure:
But then you have to postulate what event occurred to cause multiple failures across several (seemingly) redundant systems. How does some mechanical failure cause loss of all FDR data as well as thrust/reversers/landing gear? Hard to know which way Occam's razor is swinging here.
Oh, absolutely the goal is to figure out what caused the multiple failures. What I'm saying is that occam's razor says that the simplest explanation is that there was a catastrophic failure of the plane itself. There a things that pilot errors can't explain.
There you go. More evidence that this won't end up being attributed to pilot error. Or, at least needs to be explained as a pilot error.
I have not watched that video yet. I'm not sure what is meant by "emergency backup power".
If the recorders are not on the BATTERY BUS then it makes complete sense. Loss of AC power would remove power from both recorders.
I guess that's why the requirement changed in 2012 and now they must have an internal backup power supply.
And you haven't mentioned the internal batteries in the flight data recorders that you mentioned earlier.
The requirement for internal backup power wasn't put in place until 2012. The accident airplane was apparently built in 2009.
Nah, it isn't. That loaded multi-tiered question is not what Occam's Razor answers, definitionally. The Razor in this case would be pilot error/incompetence, and bob's your uncle. Not *space-aliens (*compounded redundancy-defeating catastrophic system failures, incapacitations thrown in there for good measure). Let me say it again for the people cowering in the back: occam's razor is pilot error.
That’s why you tie the CB to your wrist with a string. That way, when you do something stupid and slap your forehead, the CB is pulled before you say, “I’m an idiot!”Yeah, if I’m lining up to land a crippled airliner, pulling the CVR breaker is the top thing on my mind.
I don't think so. Remember occam's razor is that the simplest explanation that explains ALL the data is the horse to beat. Not the globally simplest, even if that leaves some of the data out of the equation.
How does startle, or any other pilot error, explain the right engine thrust reverser?
Startle response to a bird strike that messed up the right engine.
I looked at a timeline this morning and noticed that four minutes is the report of the bird strike at 8:59 and the end of the event at 9:03. So the black box stopped getting data either at the moment of the bird strike or very soon thereafter. Juan pointed out in one of his videos that there was no battery backup for the black box in this version of the plane, so this suggests that something about the bird strike caused a major power issue.
My post just before yours assumes a bird strike at -7 minutes. I got that from a video report, maybe that was incorrect at the time, or I heard it wrong.
Yeah, I see multiple timelines at 4 minutes and others at more like 7. Kind of a fundamental thing to not have clear at this point. It's possible that one timeline starts at the pilot radioing in that they had a birdstrike and the other at the actual time of the birdstrike. If true, then the three minutes you point out could indeed provide useful data.
Possibly loss of both generators. Normally, that means both engines have failed but it seems as though the airplane flew a lot longer than it would have been able to if both engines had failed.
i am guessing they still had the apu available if they lost all gens. seems they were in a hurry to get on the ground and i can't imagine a reason to be so unstable short of a raging fire on board.
Panic on the part of the pilots? Panic is not a thing that makes sense very often. And especially if they hit a flock of birds and got one or more in the windscreen - Yikes. I've been driving a truck when I hit two birds one right after the other. The first one really woke me up, and then the second one...
A lot of yelling and swearing ensued to release the energy that sort of thing causes. I can only imagine it's much worse at 150+ knots, and the "get me the hell out of here right now" you get from the fight or flight can lead to very bad decisions.
The APU would have been off. It takes about 55 seconds to start the APU and put it's generator online.
Only if they switched it on. Could be another item that was forgotten in the ensuing panic/rush.
It pains me to say thos, but could this be a magnified and more tragic version of the Grumman that landed into the Cessna?
A bird strike? I'd hope not, that's what bird strike certification testing is there for. Could they have hit so many of them to take out a windshield? Still hard to believe. Take out both windshields? I'd say very slim chance.
It would have to be a really big bird. Bird strike protection is part of the certification standards.
They didn't have time to get to that point in the checklist where they'd start the APU and put it online. With the timeline we have at this point, they would have been busy flying the teardrop pattern and landing. They didn't even have enough time to do all of the normal procedures for that.
I wondered the same thing. It's happened.
