Haven't seen this posted yet --

https://www.youtube.com/watch?v=SO3xmzoLzfI

Can't tell if they genuinely stalled it, but it did lose 300 ft of altitude. A 777 at probably near MTOW stalled (or nearly stalled) at 4000 ft MSL. Wow. Those guys were lucky.

Push the nose down and trade altitude for airspeed.

That 77F definitely needs the MCAS

jbmitt wrote:

Push the nose down and trade altitude for airspeed.

Appears that’s what they did as they were able to continue on and not end up an oil slick in the Atlantic. Requesting a high speed climb maybe there was a load or mechanical issue.

jbmitt wrote:

Push the nose down and trade altitude for airspeed.

Obviously

CATIIIevery5yrs wrote:

Appears that’s what they did as they were able to continue on and not end up an oil slick in the Atlantic. Requesting a high speed climb maybe there was a load or mechanical issue.

Maybe they retracted flap too early, not unusual for a wide body to have a clean speed above 250. Kts when heavy.

zeke wrote:

CATIIIevery5yrs wrote:

Appears that’s what they did as they were able to continue on and not end up an oil slick in the Atlantic. Requesting a high speed climb maybe there was a load or mechanical issue.

Maybe they retracted flap too early, not unusual for a wide body to have a clean speed above 250. Kts when heavy.

Many long haul B77L and B77W pilots request 270 kts on departure before they depart, obviously speed limit is 250 below 10000 but if the plane won’t stay in the air...

Antaras wrote:

That 77F definitely needs the MCAS

What is so special about this 777 (unlike the thousands of ships built before it) that requires it? Are you sure it's not because of an inept flight crew?


Sent from my iPhone using Tapatalk Pro

ArcticSEA wrote:

Antaras wrote:

That 77F definitely needs the MCAS

What is so special about this 777 (unlike the thousands of ships built before it) that requires it? Are you sure it's not because of an inept flight crew?

Nothing special, it was just a joke.

There's an actually-intelligent and knowledgeable discussion over at APC about this. They were flying JFK-ICN nonstop, and so were presumably very heavy, so one is closer to certain limits, say, between minimum maneuvering speed and flap overspeed. Still shouldn't have been an issue. Probably not a mechanical since they continued the more-than-14-hour flight to Korea and landed safely.

One thing I dislike about these VASAviation videos is that they invariably get the transcription of the audio wrong in meaningful ways, or add comments that are incorrect. This one was relatively-clean.

Believe they were below minimum speed when they retracted the flaps, losing lift. Southern generally doesn’t fly JFK-ICN non-stop so perhaps the crew miscalculated just how heavy they were.

atcdan wrote:

Many long haul B77L and B77W pilots request 270 kts on departure before they depart, obviously speed limit is 250 below 10000 but if the plane won’t stay in the air...

If for any reason they were required to keep 250 until F100/10.000, what would be the procedure? Climb on (minimum applicaple) flaps and retract above 10.000?

Cheers,
Adam

jreeves96 wrote:

Believe they were below minimum speed when they retracted the flaps, losing lift. Southern generally doesn’t fly JFK-ICN non-stop so perhaps the crew miscalculated just how heavy they were.

What is exactly is there to miscalculate? You look at the speed tape, and call for the pilot monitoring to retract flaps according to the manufacturers flap retraction schedule.

On the B777 the pilot flying calls Flaps Up when indicated airspeed reaches the the Flaps 1 minimum maneuvering speed (same applies for Flaps 15 to Flaps 5). The minimum maneuvering speeds are automatically calculated by the aircraft and displayed on the PFD speed tapes.

Southern B77L crews are very familiar with MTOW departures (766,000lbs) out of HKG to ANC or CVG-BAH.

If they were near MTOW off 22R it would most likely have been a Flaps 15 departure (they receive their takeoff data via ACARS message).

It is possible that the pilot monitoring accidentally retracted from Flaps 15 to Flaps 1 or Flaps 5 to Up

Per the company SOP for a NADP2 departure thrust is reduced to climb thrust when the flap handle is set to 5 (on a Flaps 15 takeoff) or Flaps 1 (on a Flaps 5 takeoff).

On a NADP1 departure takeoff thrust is set reduces to climb thrust upon reaching 1500 AGL and acceleration begins at 3000 AGL.

Maybe a wrong cargo weight or some input error generated wrong flap schedule speeds or a thrust setting too low? Good they reacted quick. ATC sounded calm and very helpful as well. That fast climb request sounds like they were not sure about the actual speeds required for their departure and wanted to remain on the safe side.

Another situation were some angle of attack display would be quite helpful to show the actual attitude.

Noshow wrote:

Another situation were some angle of attack display would be quite helpful to show the actual attitude.

AoA doesn't tell you attitude. It does what it says on the tin: tells you AoA. An airplane with a straight and level attitude can be at a large AoA and vice versa.

atcdan wrote:

zeke wrote:

CATIIIevery5yrs wrote:

Appears that’s what they did as they were able to continue on and not end up an oil slick in the Atlantic. Requesting a high speed climb maybe there was a load or mechanical issue.

Maybe they retracted flap too early, not unusual for a wide body to have a clean speed above 250. Kts when heavy.

Many long haul B77L and B77W pilots request 270 kts on departure before they depart, obviously speed limit is 250 below 10000 but if the plane won’t stay in the air...

Without looking at the FARs, IIRC, you can exceed 250 knots below 10,000’ if necessary in the clean (flaps retracted) configuration. That’s a somewhat common thing on the heavy departures. Of course, it’s prudent to inform ATC of that necessity, especially if departing immediately behind something that will be climbing at a slower indicated speed (CRJ 100 or 200s seemed to be the worst about that in my experience).

gloom wrote:

atcdan wrote:

Many long haul B77L and B77W pilots request 270 kts on departure before they depart, obviously speed limit is 250 below 10000 but if the plane won’t stay in the air...

If for any reason they were required to keep 250 until F100/10.000, what would be the procedure? Climb on (minimum applicaple) flaps and retract above 10.000?

Cheers,
Adam

It’s not a request ATC would ever deny, some pilots “request” it, some will “inform” us they need 280 on climb out.

Either way, we will give a couple extra miles in front depending on the preceding a/c performance and route of flight.

jbmitt wrote:

Push the nose down and trade altitude for airspeed.

At just 4000 feet, trading altitude for speed is not an easy task

B787oftheworld wrote:

jbmitt wrote:

Push the nose down and trade altitude for airspeed.

At just 4000 feet, trading altitude for speed is not an easy task

I would think not, especially in a heavily loaded 777. That's why I suggested in my OP that those guys were darn lucky. But then maybe it wasn't as dire a situation as it sounds like to me, although I imagine it's not an everyday occurrence.

Also, I don't think we know whether the airplane actually stalled. It could have just been an approach to stall. Apparently they "only" lost/surrendered 300 ft. of altitude.

jreeves96 wrote:

Believe they were below minimum speed when they retracted the flaps, losing lift. Southern generally doesn’t fly JFK-ICN non-stop so perhaps the crew miscalculated just how heavy they were.

Actually, they've been flying JFK-ICN, or JFK-NRT for about a year now. Inbound flight stops in ANC, and ORD.

bravoindia wrote:

atcdan wrote:

zeke wrote:

Maybe they retracted flap too early, not unusual for a wide body to have a clean speed above 250. Kts when heavy.

Many long haul B77L and B77W pilots request 270 kts on departure before they depart, obviously speed limit is 250 below 10000 but if the plane won’t stay in the air...

Many companies can operate at 250 on long haul and it’s not that they don’t want to have flaps in. It’s company or manufacturer required in certain conditions such as known ice that they will request high speed so they can be clean and at those weights sometimes clean is 265-280. Sometimes they get a little aggressive and are doing 340 over the ground at 8000’ lol.

I assume it’s to save fuel to climb out clean as soon as possible, as an ATC my job is to accommodate the pilots to the best of my ability. If they are climbing through 10000 in class B airspace there is nearly no risk of a collision.

What concerns me is how the sleepy-sounding PM didnt call “stall!” until the airplane starting barking at them. You’re telling me you can’t monitor a/s and give your pf a little more warning than that? Whole thing just sounded “off” to me.

phatfarmlines wrote:

I learned something new that "high-speed climbouts" can be requested below FL100. How often does this occur?

Anytime the flaps UP min maneuvering speed is greater than 250 KIAS. It’s not requested, it’s allowed as the the minimum safe speed.

[quote=]
I mean truth be told as a tower controller you wouldn’t actually know if there was any risk. Because below 14000 in our bravo there is damn plenty of risk. It’s the controllers working approach and departure that are mitigating it. But I see your point[/quote]

Well that’s my point, there is controller working any aircraft in a Bravo, meaning you don’t have guys out JFA, and if they are, they are talking to you. Since the controller has to provide IFR/ VFR separation in Bravo, I stand by my statement that there is minimal if any risk of collision between an IFR jet and any other A/C.

Back to the topic at hand though, I can’t imagine a pilot stopping accel at 250 because of a speed limit. ATC is not the sky police. I’m glad they recovered the stall so quickly.

phatfarmlines wrote:

I learned something new that "high-speed climbouts" can be requested below FL100. How often does this occur?

Its normal in many parts of the world, the US likes it’s 250 below 10. Not unusual for me to do 300-320 kts below 10 in the A350 on climb or descent.

TTailedTiger wrote:

N766UA wrote:

What concerns me is how the sleepy-sounding PM didnt call “stall!” until the airplane starting barking at them. You’re telling me you can’t monitor a/s and give your pf a little more warning than that? Whole thing just sounded “off” to me.

What in the world? The pilot flying does not just get to zone out. Both pilots should be aware of their airspeed during critical phases of flight. And they are certainly trained to cross-check each other.

Obviously. I’m referring specifically to the PM’s apparent failure to do his job and monitor, unless the airplane suddenly went from way above the low speed cue to a stall almost instantaneously. I can’t speculate on the PF as the PM is the only one featured in this audio clip.

If you notice at 00.59 in the video you can listen what i think is the 'airspeed low' caution, and they were climbling to 5000' but they never pass 4000', if the number next to the altitude is the speed, it means they were around 200 or 210 knots when they stall, so I think they select flaps 1 too fast, maybe by mistake they went from flap 15 to 1 (the notch) skipping flap 5.
Every flap setting is around 20 knots of speed.

migair54 wrote:

If you notice at 00.59 in the video you can listen what i think is the 'airspeed low' caution, and they were climbling to 5000' but they never pass 4000', if the number next to the altitude is the speed, it means they were around 200 or 210 knots when they stall, so I think they select flaps 1 too fast, maybe by mistake they went from flap 15 to 1 (the notch) skipping flap 5.
Every flap setting is around 20 knots of speed.

We can all agree something went pretty bad (at least not as planned / expected) on the departure. But, wouldn't the crew follow flap retraction schedule? I thought that once you are above the green flap speed indication (e.g. Flap 5), you select Flap 5 (from previous setting; e.g. Flap 10). Any pilot's comment on this always appreciated. This process was explained to me by several B744 pilots, hence it is only I am aware.

If such retraction was by a mistake, it is unfortunate, but I am glad to see the best possible outcome out of this. Will we ever know what was the real cause? It would benefit all, but I am not sure if details of such incident will be publicly available. Unfortunately, we can only speculate what happened.

Best!

Juan Browne's take on this is up --

https://www.youtube.com/watch?v=a-siCbCA_yE

He's calling it a "low speed event."

N766UA wrote:

Obviously. I’m referring specifically to the PM’s apparent failure to do his job and monitor, unless the airplane suddenly went from way above the low speed cue to a stall almost instantaneously. I can’t speculate on the PF as the PM is the only one featured in this audio clip.

As you might have noticed, there was a bit of confusion regarding the departure frequency initially. So it is likely that the PM was double checking frequencies on the SID charts/EFB and com panels and not just staring at the PFD all the time.

How about not immediately jumping to conclusions about someone failing to perform their job based on about 0% knowledge of what was going on .

Another issue not mention is bank angle . It’s been 3 years but it think the 777 had a bank angle restriction of like 15% with F5 or 1 and up and speed less than VZF. Gets you stick shaker warning if your not careful.

filejw wrote:

Another issue not mention is bank angle

They were flying runway heading for the whole event.

It always surprise me that many pilots, and experienced ones at that, still think the limit is 250 kts below 10 in US airspace.
It's quite clear in the regulations that the limit is “250 kts, or flaps up clean speed, whichever is higher ".

Tartarus wrote:

It's quite clear in the regulations that the limit is “250 kts, or flaps up clean speed, whichever is higher ".

So if flaps up is at 260 kts you can fly that speed below 10000 without having to say anything to ATC?

hivue wrote:

Tartarus wrote:

It's quite clear in the regulations that the limit is “250 kts, or flaps up clean speed, whichever is higher ".

So if flaps up is at 260 kts you can fly that speed below 10000 without having to say anything to ATC?

If your minimum clean speed is above 250 kts, you advise ATC. I do not believe that ATC would refuse such request. Sooner you advise, the better they can coordinate. But I remember, quite regularly, hearing such requests on KEWR Tower frequency for departing planes (2002 - 2008). I still believe that you have to advise ATC as anything above 250 kts and below 10,000 feet is not standard.

In Europe, you frequently receive clearance to maintain speed greater than 250 kts (for arriving aircraft). This is also not an unusual occurrence.

Best!
Andrej

Tartarus wrote:

It always surprise me that many pilots, and experienced ones at that, still think the limit is 250 kts below 10 in US airspace.
It's quite clear in the regulations that the limit is “250 kts, or flaps up clean speed, whichever is higher ".

FAR 91.117 can only be exceeded with an FAA exception, ATC cannot provide a clearance to exceed that. Many operators have an FAA exception in their ops spec which gives them the ability to fly at 250 or min clean speed, often that is where departures take them over water away from other airports. Fact that the FAA issues these exceptions goes against your statement above, if it wasn’t required the FAA wouldn’t issue it.

Strictly speaking the FAR requires 250 below 10 (sometimes even maximum of 200 kts), it does allow 250 to be exceeded unless the minimum safe speed is above 250, it does not say minimum clean speed. Generally speaking the only reason where the safe speed would be above 250 kts would be due to icing or a mechanical issue. Airliners can easily maintain 250 kts or below 10 safely, we do it on every departure or arrival, it just requires some slat and/or flap. Minimum clean speed is not a safety issue unless icing is present, it is for efficiency.

The history behind this is a mid air collision around 50 years ago, they have done a trial to remove it, however the restriction is still in place.

Have a look at this letter from the FAA to CO https://www.faa.gov/about/office_org/he ... 0-%20(2010)%20legal%20interpretation.pdf

In that letter they say that 91.117 does not distinguish on configuration for different portions of an operation, if you can achieve the speed requirements by configuration you are to do so.

280kt minimum for DL 777/747s was a very common request at DTW. Oddly enough requests from heavy jets were rare on the STAAV departure at LAS with its 220kt restriction, though pilots were usually happy to get it deleted.

zeke wrote:

Strictly speaking the FAR requires 250 below 10 (sometimes even maximum of 200 kts), it does allow 250 to be exceeded unless the minimum safe speed is above 250, it does not say minimum clean speed. Generally speaking the only reason where the safe speed would be above 250 kts would be due to icing or a mechanical issue. Airliners can easily maintain 250 kts or below 10 safely, we do it on every departure or arrival, it just requires some slat and/or flap. Minimum clean speed is not a safety issue unless icing is present, it is for efficiency.

The history behind this is a mid air collision around 50 years ago, they have done a trial to remove it, however the restriction is still in place.

Have a look at this letter from the FAA to CO https://www.faa.gov/about/office_org/he ... 0-%20(2010)%20legal%20interpretation.pdf

In that letter they say that 91.117 does not distinguish on configuration for different portions of an operation, if you can achieve the speed requirements by configuration you are to do so.

Thanks, Zeke, for your crystal-clear and authoritative post!

While the GC reading is correct, cleaning up and climbing at min clean speed even exceeding 250 knots has been acceptable procedure for decades, at least since the 747 went into wide use.

GalaxyFlyer wrote:

While the GC reading is correct, cleaning up and climbing at min clean speed even exceeding 250 knots has been acceptable procedure for decades, at least since the 747 went into wide use.

The caveat there is you do not necessary know if the FAA has provided that operator with an exception, I know many operators in this part of the world had in their part 129 OpsSpec the exception to exceed that, and they are generally departing westbound from the west coast (the 250 below 10 only applies for the first 12 miles overwater anyway) with no other airports when over water, so lower traffic density. I heard US flag carries had similar.

This is not something that is approved on the spot, operators submit an application, the FAA does a risk assessment, and then provide the written exception.