Southern Air 777 stall and recovery after takeoff, Nov 15th
 

flightradar24

Departure out of JFK, audio reveals airspeed low warning and also the config warning (overspeed?) likely during recovery.

Avherald quotes about 200' height loss during the event; ADS-B (via FR24) suggests more like 750'.

Hand-flying?

https://cimg0.ibsrv.net/gimg/pprune....621f2c76db.jpg

First Officer handling?

Strange response. Many FO's handle manually better than CP's.

I was thinking that the a/c was not being flown using automatics. Employing automation relatively quickly is good practice in a busy TMA like that of JFK. It reduces the workload on the non-handling pilot. And at night, it removes the risk of somatogravic illusions and the like, which have caused accidents on jets not so long back.(Gulf Air 320, Flash B737, etc)

Hand-flying should have no influence, it is expected that both sides of the flight deck are competent in hand-flying at this point in their careers.
Maybe inadvertently retracting from flaps 5 to flaps up, instead of flaps 1?

Why would they request a fast climb afterwards then?

To increase the margin on low-speed buffer due to high gross weight? Vref+80 on the Boeing type I currently fly is over 250kt at Max TOW.
Take a turbulent departure and keep normal speed (250 below 10000), you are in for a nasty surprise.

Whas the load and balance sheet accurate, is the first question here.

That's the point.

Yikes - not a nice thing to hear on frequency. Handled well.

I wonder was it a sudden tail wind mixed with heavy laden aircraft? 250kias could be surprisingly close to the buffer zone I imagine

If min speed (Vref+80) is greater than 250kts, you can fly at the higher speed. Max TOW, our 763 has +80 of 256kts, so that’s what we’d fly.

The Kennedy 5 departure doesn't contain a published 250 knot restriction. Therefore only the FAR is applicable, and that states you can go to clean speed. I don't know why anyone wouldn't. Possibly an increasing tailwind, but 22s are generally in use with southerly or westerly wind. Wouldn't expect it until the turn.

Couple of things stand out:

Firstly that the stall warning sounds like it worked like it says on the tin. And the recovery was initiated.
Secondly there was a radio frequency distraction possibly increasing the PM's time head down.

Glad the piloting came back to save the situation!

Possible early ALT capture with the autopilot engaged...need to watch your speed as the autopilot will fly the capture profile without speed protection. Heavy weight and/or wind shift are equally possible but even low level if you have a high rate of climb as it goes into ALT or VNAV ALT watch out for the speed decay.

The PM sounded sleepy on the radio. Then the stall woke him up! :eek:

So much utter nonsense being written here. Those that currently fly heavy Boeing types here have probably answered the question. Had it not been caught on the RT no one would have been any of the wiser. Well handled but nothing any competent crew couldn’t handle.

"No one would have been the wiser", maybe not, until the operational data dump flagged up a stall on climb out. Not exactly an everyday event.

Contact Approach

Regardless, still earns them tea and biscuits with the CP soon thereafter. Not normally pleasant conversations.

All utter nonsense indeed.

Except nike.

Who is 100% correct.

It might show up on the flight data monitor so best to own up rather than get pulled in by the safety department. Recovering with a 750’ height loss isn’t too bad but obviously being close to the ground they couldn’t afford a massive drop. An early recognition and prompt recovery action probably helped.

Simulator stall training often involves the fully developed case at higher altitudes where the height loss is significant and the time involved lengthy before the aircraft unstalls. More emphasis on recovery from low altitude events minimising height loss may be called for.

Alway be really careful in ALT ACQ mode with autopilot engaged.

Nike is correct if the AC captures early, speed can decay rapidly after early ALT capture ,only solution is to hit ALT HOLD wait for the nose to drop then engage VS when a more sensible ROC is indicated. It’s a particular issues on freighters at light weight with low initial departure altitude. Or they have entered an incorrect ZFW in the FMC.

The autopilot and authothrottle on Boeing aircraft has always been a dog and not worthy of being trusted. Even on the latest machines. That's why Boeing pilots are a more vigilant and twitchy bunch.

allaru

Why not klick klick, klick klick??? Drop down a level of automation or all? fly it stabilise it and then try again...

With the power of open information, comes great responsibility.
 

This thread, this incident, wether accurate or not, together with similar discussions based on 'open information', challenge fundamental aspects of our profession and flight safety.
Many countries protect the rights of crews with confidentiality of data, FDR / CVR which enables professional investigation and review. Yet with advancing technology and communication, accidents and incidents are now exposed to extremes of human behaviour with biased, inaccurate, and possibly deliberate misleading discussions of unvalidated data.

What hope for a just culture, reasoned judgement, peer review.

These are a fact of modern life, but safety still requires thoughtful and considered behaviour in commenting on what at best in unsubstantiated information - incident data or posts.
Irrespective of wether posters are from the industry, travelling public, or just spotters, … professionalism demands thoughtful responses.

"… information may want to be free, but it also wants to kill us."

Lots of conjecture here. I shall just wait for the Report, as no one really knows what happened, possibly not even the Pilots, sometimes :mad: happens, you deal with it and find out all the facts later during an investigation.

Lets be careful out there

Why reference the minimum speed to Vref rather than V2? Is it a Boeing thing that I have missed?

Of course if the aircraft is not behaving as it should, take control.

But this is a modern 777 right? Why would modern design allow this sort of thing to happen? (notwithstanding a possible ZFM error). Also the comments about Vref+80: it seems odd to me that a (heavy) aircraft can not keep to 250kts?

Alex. The min manoeuvring speeds for various flap settings are based on Vref. So min clean in Vref+80, min speed Flap 1 is +60, F5 is +40. etc.

We could fly at 250, but not clean. If my MTOW 763 needed to fly at 250 I’d need to keep F1 (min clean at this weight is 256).

ps. I have no idea what the equivalent speeds would be for a 777 but I’m guessing somewhat higher.

Why not klick klicken.....because coming out of automation usually results in a huge F'Up....especially in a busy traffic environment with a high rate of climb. The ALT hold VS method works well but it pays to brief it before hand, the trick is to wait for the nose to drop and the VS to come down, otherwise if you try to engage VS too early it will just recapture again. Freighters also have a higher flat rating compared to the pax aircraft so there can be huge amount of excess power even at max derate. Min clean can be above 250 at heavy weights, but they may have been empty.

"Absence of attitude protection in the autopilot's altitude capture mode"

A different type but same issue, aircraft flown by test pilots but still fatal......

https://en.wikipedia.org/wiki/Airbus...rie_Flight_129

allaru

I disagree. If automation has caused the tits up then the only way is to hand fly it. And I thought by now this is Industrie standard. Especially in the last few years were we have seen accidents through undesired aircraft states. This is basically were UPRT training comes in. Recover from the stall stabilise the flight path, then rebuild the autoflight system. Trying to fix a bad situation by fiddling with the FGS is not the way to go.
And I am not saying that this happend here. I was just replying to a nother comment.

allaru


I don’t fly a 777, but I disagree with this. If the automation is trying to kill me, the solution isn’t more automation. Especially in a potential stall.

(Bearing in mind that we really have no idea what caused the low energy situation. Everything here is speculation.)

This doesn't seem so hard to imagine. I recall from personal experience that when doing an ICAO B Noise Abatement departure that any premature restraction of the flaps would almost immediately cause the stall warning to activate. The PM had to pay attention to the flap retraction schedule before moving the flap handle to the next retracted position, and if by chnce he went through the gate to the next flap setting you could expect that shaker to activate almost immediately. Moving the flap lever to the correct position would correct the problem along with lowering the nose at the same time. Attention getter for sure!

allaru

Sounds like you’re scared of hand flying.

Stall or stall warning? I would be 99% sure it was the latter.

Once you are in ALT, it follows a trajectory based on the rate-of-climb when it acquired. If you’ve flown through a positive shear/gradient and maintained airspeed, the instantaneous climb rate at capture might be above what the aircraft can sustain without trading speed for height. If the A/P is in, you have to disconnect or accept a loss of airspeed during the capture.