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NTSB issues investigative update on B-767 runway excursion accident in Miami

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Re: NTSB issues investigative update on B-767 runway excursion accident in Miami

#281

Post by fragmede »

pluc wrote: post #211
VBprogrammer wrote: post #174

Earlier quoted context omitted.

Having pilots fighting over the controls is not a situation anyone wants. The pilot monitoring saying go around should have caused an immediate reaction, the human factors behind why it didn't will probably feature prominently in the post-accident actions.

Wouldn't be a case of "if I fix it then there was nothing wrong"? How do you, as an inferior rank, step in to correct something that you think is going to happen? Imagine the inferior officer steps in and lands the plane, wouldn't the superior officer say well duh that's what I was doing why did you intervene? It's an interesting conundrum, I think, and may exacerbate the reaction or lack thereof..

linked elsewhere in this thread: CRM is standard practice aboard airplanes. https://en.wikipedia.org/wiki/Crew_resource_management

Re: NTSB issues investigative update on B-767 runway excursion accident in Miami

#282

Post by VBprogrammer »

stouset wrote: post #280
VBprogrammer wrote: post #268

Earlier quoted context omitted.

The power dynamic in training is obviously very different during training where the instructor is pilot in command. Making the assumption the PM could have taken control cleanly if the power dynamic was so poor that they weren't able to demand a go-around seems iffy, typical stabilised approach gates are 500ft in VMC, with an aircraft travelling 3nm a minute, 40 seconds before touchdown. But as I said, the human fact…

My response was to your point about “fighting over the controls”, as if there would have been a tug of war on the yoke as the FO tried to wrest control of the plane from the captain which is nonsense. If anything, it would have been yet one more opportunity to avert catastrophe and perform a go-around. Pilots are trained for this, and it makes less than zero sense for a PM to fail to take the controls from a PF who i…

> If you have never actually been behind the controls of an aircraft, please just stop trying to confidently assert things about this subject.

That's a lot of assumptions.

Re: NTSB issues investigative update on B-767 runway excursion accident in Miami

#283

Post by stouset »

mrngld wrote: post #220
ibejoeb wrote: post #197

Earlier quoted context omitted.

The PM got his rating about 18 months ago. The PF only got his this past May. The PM had more overall hours, but this is looking a lot like a skills issue. He was flying an unstable approach. He wasn't configured for landing. This pairing, considering past incidents with similar airframe vs. total hours disparity, really does look to be bad practice. You've got to acknowledge the human psychology. Part of it is proba…

I really don't think time in this particular type is a factor. None of what I've heard or read has anything to do with familiarity with its unique systems. Everything sounds like sloppy flying. Sounds like he, the PF/PIC/Captain, started the descent late, stayed too high, didn't manage the power curve well, landed long and fast and willfully ignored his first officer. One bad decision after another where instead of p…

Yeah, time in this type could be argued as a reason they weren’t properly configured or on a stable approach, but that is exactly why go-arounds exist. Mistakes happen, errors get made, so you go TOGA, fly a holding pattern until you get sorted, then try again. Happens at every airport every single day. No harm no foul.

That is not the reason this incident happened. This happened because the pilots continued to put it on the ground while ignoring at least a dozen clear and unambiguous indicators to abort the approach and go around.

Re: NTSB issues investigative update on B-767 runway excursion accident in Miami

#284

Post by stouset »

detourdog wrote: post #215
kashunstva wrote: post #184

The details of course matter; but the overarching principle put on stark display here is that if you don’t meet stabilized approach criteria (on-speed, on-glidepath, minimal necessary flight control deflections) at the 1000 ft AGL gate, go around. Yes grey areas exist but this approach never became stabilized. The whole approach was a missed opportunity to go around. I am a pilot; and although I don’t fly large trans…

If there are factors that need to be met it seems like a red indicator light should trigger a go around.

There were quite literally multiple warning alarms that went off that should have automatically triggered this exact response.

Re: NTSB issues investigative update on B-767 runway excursion accident in Miami

#285

Post by stouset »

xenadu02 wrote: post #84

Pilot here but not ATP or Jet rated. When you try to land with too much energy the airplane refuses. When you get within a wingspan or two of the ground then ground effect starts giving you more and more lift. That plus excess speed means the airplane simply will not come down. To force it down you lower the nose but that can end up castering on the nose wheel, starting a PIO event (pilot-induced oscillation), or as…

The thing I’ve come to appreciate between my first few days in a sim, a lot of sim time, and then actual time behind a yoke is that like a lot of things, landing is peaceful and easy if you’ve done all the prep ahead of time. Which is precisely your point.

The further in advance you cut power, descend, and get your airspeed set, you’ll find you have plenty of time to go over your checklists, mentally rehearse, and get configured. By the time you’re touching down, the plane wants to be on the ground.

If you’re coming in high and fast, you have significantly abbreviated time. And you’re constantly fighting airspeed and altitude. If both are high, trying to lose one just increases the other. It’s a losing battle and one you’re fighting on an accelerated and accelerating time frame.

Re: NTSB issues investigative update on B-767 runway excursion accident in Miami

#286

Post by singleshot_ »

stouset wrote: post #280
VBprogrammer wrote: post #268

Earlier quoted context omitted.

The power dynamic in training is obviously very different during training where the instructor is pilot in command. Making the assumption the PM could have taken control cleanly if the power dynamic was so poor that they weren't able to demand a go-around seems iffy, typical stabilised approach gates are 500ft in VMC, with an aircraft travelling 3nm a minute, 40 seconds before touchdown. But as I said, the human fact…

My response was to your point about “fighting over the controls”, as if there would have been a tug of war on the yoke as the FO tried to wrest control of the plane from the captain which is nonsense. If anything, it would have been yet one more opportunity to avert catastrophe and perform a go-around. Pilots are trained for this, and it makes less than zero sense for a PM to fail to take the controls from a PF who i…

> If you have never actually _______, please just stop trying to confidently assert things about this subject.

If this site had a slogan, I think you just guessed it

Re: NTSB issues investigative update on B-767 runway excursion accident in Miami

#287

Post by bell-cot »

mitxela wrote: post #256
bell-cot wrote: post #205

Earlier quoted context omitted.

I'm no Amazon fan, but that was routine in trucking before Bezos was even born. Similar to farmers working in the fields - they didn't walk all the way back to the farmhouse if they had to pee.

It's not their choice though, they have to . I wouldn't care much if they chose to.

They also have to work in the rain, and in the snow, and work extra hours before Christmas, and lift heavy boxes, and all sorts of other stuff goes with the turf when you're a trucker.

That I've heard, with the insane pace of work that Amazon tries to force 'em to maintain, 3,600,000 milliseconds per hour, the job would be very little better if they somehow had 5-star resort bathrooms folded into hyperspace inside their trucks.

Re: NTSB issues investigative update on B-767 runway excursion accident in Miami

#288

Post by xenadu02 »

rbanffy wrote: post #219
xenadu02 wrote: post #78

Earlier quoted context omitted.

No, the left main was not on the ground after touchdown for some time. The aircraft will not auto-deploy the spoilers nor autobrake until it senses weight on weels. It also locks out the thrust reversers. All for obvious reasons. The left wing was lifting because they came in way too fast. 30-40 knots above final approach speed. That's why they landed so flat - if they had assumed correct flare AoA the airplane would…

> The aircraft will not auto-deploy the spoilers nor autobrake until it senses weight on weels. It also locks out the thrust reversers. All for obvious reasons. While I agree the obvious course of action would be a go-around, a manual override for when you know doing the stupid thing is the least unsafe thing to do would be handy.

Part of the problem is they got into this mess because they were behind the airplane and had been behind it for a while. That means less time to do your normal procedures putting you further behind. That raises stress and causes mistakes. That cycle feeds back on itself making everything worse.

They'd have needed the mental bandwidth to notice on the EICAS display that the spoilers weren't deploying to even know to manually trigger them. Given how far behind they were noticing that would be highly unlikely. Under high stress you revert to your training or habits and manual spoiler deployment is just not something you need to do.

Their bank angle (for lack of a better term) was probably not enough to notice unless they had the mental bandwidth to pay close attention.

This is a common thing in these sorts of accidents: if you have the mental bandwidth to deal with these problems you'd have been properly setting yourself up for landing 30 minutes before you started and you wouldn't be in this mess to begin with.

This also represents a safety margin during normal flights: If everything is done by-the-book and going well then you are calm, collected, and you have the mental resources available to do quick instrument scans after touching down and potentially notice spoilers did not deploy - and you have the extra runway to account for the few seconds of delay it takes to notice then manually deploy them.

Re: NTSB issues investigative update on B-767 runway excursion accident in Miami

#289

Post by arcfour »

AdamN wrote: post #213
arcfour wrote: post #106

Earlier quoted context omitted.

> unclear how speed didn't increase How can you comment as if you are knowledgeable enough about aviation to speak on this with authority, but you aren't aware that turbofan engines don't have instant throttle response and need time (up to 8 seconds) to spool up? I think a little more restraint is warranted in something like this if you don't know something that basic. You can actually do the math to work backwards a…

We're not jurors or NTSB investigators - this is just a public messageboard on a tech-focused platform. It's totally fine to speculate and wonder here ... and to be corrected respectfully.

Was anything I said disrespectful? It is not intended to be, but it may read as somewhat stern; that's more because speculating without having the fundamentals down is not what I expect from HN. The knowledge in question isn't arcane or a secret.

Re: NTSB issues investigative update on B-767 runway excursion accident in Miami

#290

Post by mrguyorama »

ofcrpls wrote: post #7
bradly wrote: post #4

> 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.

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.

I would expect, that if they tried to deploy thrust reversers, that event would have been included in this summary. If such an assumption is safe, then the implication is that they didn't even try to deploy reverse thrust which is insane.

Similarly, it isn't specified anywhere, but it took TEN FULL SECONDS of contact with the runway between first wheel down and last wheel down. Why didn't spoilers deploy and bring down the third wheel way faster than that? Do spoilers require all three wheels already down? Why, this is exactly what they are for!

There was also 7 seconds between first wheel touchdown and first application of brakes. That would seem to mean they were confused and autobrakes didn't function, but then the third wheel comes down, which should have let autobrakes and thrust reversers deploy, yet the aircraft only lost 14 knots in the 4 seconds between that event and the throttles being moved to go around. That is consistent with only the existing braking effort, which expended a similar speed in the previous 4 seconds. Brake performance may have been reduced by a slick runway maybe.

15 full seconds between first wheel touchdown and an actual decision to go around being executed. 3000 feet is a rather significant portion of any runway.

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