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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

#101

Post by tgsovlerkhgsel »

loeg wrote: post #90
JumpCrisscross wrote: post #69

Earlier quoted context omitted.

> While they were still late in calling a go-around (they should have done it before being anywhere close to touching down due to their unstable approach) Barring a massive tailwind, they had enough groundspeed to go around at touchdown (158 kts). I think we'll find throttling to G-A and then aborting the G-A caused the crash. If they'd committed to landing they at least wouldn't have overshot with that much energy.…

They didn't have much runway left at 00:15 and were far slower than 158 at that point. They came in far too fast, descending too rapidly; first touch was >50% down the runway, and they didn't get the left gear down, so the spoilers and brakes didn't apply until even later. Should have had a better approach; should have gone around before they even touched the ground; conditional on the bad approach and first touch, t…

> But they made the wrong choices at all of those points.

This tends to be something we see in most incidents, because the cases where someone makes the right choice at one of the points tend to not become incidents.

An interesting thought is that the more obviously bad/incompetent/terrible decisions or (in)actions were involved in an incident, the better it is, because it means more things had to go wrong for a disaster to occur (more slices of cheese in the Swiss Cheese model).

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

#102

Post by AnimalMuppet »

dghlsakjg wrote: post #48
jtchang wrote: post #40

Earlier quoted context omitted.

Southwest airlines had a culture of turning around fast at the gate. So maybe no explicit policy but culture can drive unintended consequences and decisions.

Fast gate turnarounds have nothing to do with what happens in the cockpit. That affects the cleaning crews. Take a look at Southwest's safety record. I believe they have 1 fatality due to an air incident in their history due to an uncontained engine failure that was not related to maintenance.

1 passenger fatality. They also have at least one ground fatality. (Still very impressive!)

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

#103

Post by cube00 »

cyberrock wrote: post #97

Looking at it from the glass-half-full perspective, I'm impressed that pilots declare go-around as often as they do. As someone who sometimes can't decide whether I should declare a production incident (even if it's not my change), I wonder if it's possible to learn that decisiveness.

> can't decide whether I should declare a production incident

A supportive culture encourages you to declare early at the first sign you feel something isn't right.

The fact you're struggling to decide means it should be declared but you feel some negative force if ends up not as serious as you think.

A supportive culture will work with you and if necessary down grade the priority if it can wait until a regular release cycle.

It's the same rot that set into Telstra https://news.ycombinator.com/item?id=49534127

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

#104

Post by iamtedd »

cyberrock wrote: post #97

Looking at it from the glass-half-full perspective, I'm impressed that pilots declare go-around as often as they do. As someone who sometimes can't decide whether I should declare a production incident (even if it's not my change), I wonder if it's possible to learn that decisiveness.

Way better to abort and try again, than commit and run the risk of something going wrong. What harm is there in doing a go around if you can? They have plenty of fuel to try multiple times, and have clearance to do so if required.

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

#105

Post by psunavy03 »

phire wrote: post #91
xenadu02 wrote: post #81

Earlier quoted context omitted.

Spool up time is 8-10s on high-bypass turbofan engines. They tried to go around maybe 1000ft from the end of the runway? It was far far too late to even try it at that point. Sadly if they had made the call earlier they were going so fast they were basically at rotation speed when they touched down so could have just pulled back and gotten into the air. They landed flat (and the left wing refused to come down) becaus…

Isn’t there a regulation for idle to full go-around thrust in a maximum of 8 seconds? If so, it’s tight… but i feel like they should have made it if they had stuck to that plan. They commanded full power 15 seconds before the crash, and were pretty close to (if not slightly above) their stall speed (depends on load). I suspect they just needed another 10-20 knots and enough energy to climb.

The fact they were even in that situation is only worth philosophizing about to a point. Because they were only in that situation due to what appears to be a series of totally unacceptable decisions that got them there. Based on everything that's come out, I'm comfortable saying as a former military aviator that in my opinion, this crash happened due to a complete failure of airmanship on the part of both crew members.

- a) Flying an unacceptably sloppy approach that put them on short final going that fast, high, and overpowered. Professionalism is being on airspeed and/or angle of attack and on glidepath . . . no excuses.

- b) Responding to a) by trying to force the jet onto the runway, when any aircrew member with half a brain should understand how badly you're going to float in ground effect when you're that fast and that overpowered. And what that's going to in turn do to your spoilers and thrust reversers that depend on weight-on-wheels before activating. Professionalism is recognizing a botched approach, swallowing your ego, and taking it the hell around.

- c) The pilot not flying sitting there like a coward and not taking the controls from the pilot flying. If someone hits a go-around criterion and isn't going around, YOU TAKE THE CONTROLS AND EXECUTE ONE. Professionalism is proper crew coordination and proper assertiveness in the cockpit.

This whole thing seems to just boil down to a complete failure of airmanship and a complete failure of professionalism all around. If I'd done that or allowed my pilot to do that, I'd expect to have had my wings pulled. If the investigation reveals more, I'll change my mind. But it ain't looking good.

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

#106

Post by arcfour »

eh_why_not wrote: post #65

So many mistakes. A notable part is this: >> CVR: 00:15 A pilot called for a go-around. >> FDR: 00:15 Brakes were released at a groundspeed of 120 knots and throttles were increased to a value consistent with go-around thrust. >> FDR: 00:11 The throttles were reduced to idle power and the brakes were re-applied. The groundspeed was 117 knots. The throttles remained at idle, and brakes remained applied until the end o…

> 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 and approximate how much thrust the engines were producing during that time, which was about 15,000 lbf (vs ~120,000 lbf max thrust for a 767-300er) which reduced how quickly they were decelerating by... Maybe a few % or so. But they didn't start accelerating yet. They would have in another second or two, however.

I'll agree that they should have gone around far earlier; getting non-spurious GPWS callouts on final because you're trying to dive and find the glideslope is... Crazy, and configuring landing flaps over the numbers is also crazy, and so is landing 10-20kts faster than the highest possible Vref value for the type, and everything else. But that's fairly obvious...

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

#107

Post by SoftTalker »

cyberrock wrote: post #97

Looking at it from the glass-half-full perspective, I'm impressed that pilots declare go-around as often as they do. As someone who sometimes can't decide whether I should declare a production incident (even if it's not my change), I wonder if it's possible to learn that decisiveness.

That's why there are standards that define when to go around. If you aren't stable, on glide slope, at proper airspeed, and the before-landing checklist complete at 1000 feet, a go-around is mandatory. There's no choice at that point (or should not be).

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

#108

Post by psunavy03 »

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…

Did fly jets, although not transport-class ones. Just to hammer home that everything here is correct, and the common thread through all aircraft types is disciplined execution.

You fly an approach on airspeed and/or angle of attack, and on glideslope. Period. You're either there or you're correcting to get there, and you're correcting at a point that you don't need huge oh-my-God corrections in close. If you can't do that, sucks to be you, take your waveoff like a real man or woman, and next time suck less.

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

#109

Post by twisteriffic »

dghlsakjg wrote: post #76
cucumber3732842 wrote: post #57

Earlier quoted context omitted.

Pilot gets more veto power than the crane guy who gets more veto power than the residential concrete crew but they all still get talked to if they can't get their jobs done. I didn't say the same. I said the pressure was probably there too. But you can construe it as the former because that's a way easier thing to argue with.

Fair enough. I assume that since the NTSB database makes every single incident investigation public you can point to at least one instance where an ATP was pressured into avoiding a go around?

I mean... The problem is common enough that there are industry specific terms to describe it. Go search that database for "commercial pressure" and I'm certain you'll find what your sealioning self is demanding from everyone else.

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

#110

Post by psunavy03 »

grepfru_it wrote: post #80
addaon wrote: post #8

Earlier quoted context omitted.

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 ne…

Nothing prevented the pilots from applying speedbrakes. Nothing prevented the pilots from deploying spoilers. However the pilots were busy doing other things and, this is where your comment comes in, relied on automatic systems which require weight on the wheels

The problem occurred way behind that, when they refused to take a botched approach around. Everything else was just them doubling down on a bad decision over and over.
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