ANA roller coaster

[Wannabe Flyer]

https://youtu.be/Ds5Z8b3l0FE

[Flingwing47]

oops, dropped my phone

[WingNut60]

Someone care to explain the dynamics there?
It all happened pretty fast.

[wiedehopf]

Marginally better link:
https://twitter.com/i/status/1032981567361015808

[Capn Bloggs]

"Slope!" .. :}

[Wannabe Flyer]

From the clearer links above seem to be 2 separate attempts with about the same roller coaster effect

[fox niner]

Transcript HOT MIKE 1:
”So when I was still flying Twin Otters in the Caribbean, we used to approach St. barths. And when right over the hill, you had to push down like THIS....to make it to the runway.”

[sitigeltfel]

"I said Captain-san, not Khe-Sanh!"

[Herod]

Go-around...good decision.

[FullWings]

It’s hard to say without the QAR/FDR trace whether the dramatic pitch down was intentional or caused by environmental conditions. Does look a bit hairy either way and they binned the approach shortly after which I’m sure most of us would agree with.

NRT (if that’s where it is) has some “interesting” effects in strong winds - definitely a not a airport for any complacency...

[Eutychus]

The, um, Daily Star (https://www.dailystar.co.uk/news/world-news/725877/Passenger-plane-nosedives-landing-turbulence-windshear-Typhoon-Cimarron-video) says it was at Narita and that the landing was during Typhoon Cimarron.

[megan]

Thread running in Tech Log which offers this as a possible reason.

https://aviation-safety.net/database/record.php?id=20120214-0

[atr-drivr]

Thread running in Tech Log which offers this as a possible reason.

https://aviation-safety.net/database/record.php?id=20120214-0

Airbus...was this not a 787?

[Concours77]

Airbus...was this not a 787?


ANA was first Dreamliner customer. That is a 787. The wings, tips and gear tell it all.

[megan]

Read the postings. You missed the salient point in the Airbus report. The pilot flying (PF) was a captain-under-training, occupying the left seat; the right seat was occupied by a training captain ............. both pilots sensed that the aircraft was sinking rapidly and both initiated a TOGA 10 go-around. The PF momentarily retarded the thrust levers to idle before advancing them to the TOGA (Takeoff and Go-around) position. At the same time, he made a full forward sidestick input The PF brought his muscle memory from the right seat to the left, go around from the right seat, pull with the right and push with the left.

https://www.pprune.org/tech-log/612662-ana-b787-interesting-go-around.html

[hans brinker]

Read the postings. You missed the salient point in the Airbus report.The PF brought his muscle memory from the right seat to the left, go around from the right seat, pull with the right and push with the left.

https://www.pprune.org/tech-log/612662-ana-b787-interesting-go-around.html

You missed the salient point that that report was about another flight.

[lomapaseo]

There is a danger in mis-leading readers when another complex incident is brought into a prang/incient without developing a linkage to salient facts.

[Concours77]

There is a danger in mis-leading readers when another complex incident is brought into a prang/incient without developing a linkage to salient facts.

A good start to a discussion is the fact that from the video, the first input was Nose Up. A robust Nose Up. Followed by an abrupt and alarming Nose Down. Will we hear the shaker on the CVR?

If the Nose Up was not commanded, I’ll call it an excursion.

[clark y]

Chasing the glideslope?

[EternalNY1]

Chasing the glideslope?


Certainly not.

That Airbus incident where the captain moved from the right seat to the left is interesting.

What used to be "raise the nose, advance the throttle" would be "lower the nose, reduce the throttle" when in the left seat.

[Cough]

Read the postings. You missed the salient point in the Airbus report.The PF brought his muscle memory from the right seat to the left, go around from the right seat, pull with the right and push with the left.

https://www.pprune.org/tech-log/612662-ana-b787-interesting-go-around.html

On a Boeing, you push the TOGA button on the thrust levers to activate the G/A mode. On the Airbus, you push the thrust levers all the way forward...

I get where you are coming from, but believe due to the completely different feel between the two manufacturers I believe that wasn't the case here...

[glad rag]

So what caused the pitch down?

[Concours77]

I vote “currently undetermined”.....

[Chris2303]

Could that be a PIO?

[Capn Bloggs]

So what caused the pitch down?
Pretty obvious. The aeroplane was probably in-trim that close to the ground. No windshear or upset is going to cause that gyration if the aeroplane was left to it's own devices. If the autopilot was engaged, there is no way (I hope!) that it would have put in such a gross nose-down input. That leaves only one thing: the hand that was attached to the control column...

[megan]

A reference to an accident I mentioned some time ago, it can happen, though we don't know the reason in this particular case, Pprune does canvas possibilities.

https://www.pprune.org/military-aviation/605164-p38-lightning-question-3.html#post10053469

[josephfeatherweight]

That leaves only one thing: the hand that was attached to the control column...
I'll confidently put my money on that, too!

[FCeng84]

If this turns out to be the result of the hand attached to the column, the next (and more important question to me) is what was the intent of brain controlling that hand and what inputs was that brain using to decide how to control that hand? Was the pilot's concentration purely out the window? If the pilot was focused on instrumentation, which displays and which parameters? Was the pilot closing the loop on glideslope, flight director, pitch attitude, vertical speed, anything else? The 787 has a HUD so the question of which display was being used also comes into play, HUD vs. PFD. A challenge in sorting these things out is that often the pilot's loop closure becomes so intuitive after years of experience that they are not always aware of what inputs they are responding to.

[wheels_down]

Reminded me of this one.

https://www.youtube.com/watch?v=PatP3YEVj1Y

[Kraus]

Take a look at B767 ANA heavy landing Narita JA610A and you’ll see some similarities in technique.

[megan]

A challenge in sorting these things out is that often the pilot's loop closure becomes so intuitive after years of experience that they are not always aware of what inputs they are responding to. A bit like riding a bike.

https://ed.ted.com/featured/bf2mRAfC

To plagiarise, I learned that knowledge does not equal understanding, and I learned that truth is truth. No matter what I think about it. So be very careful how you interpret things because you’re looking at the world with a bias whether you think you are or not.

[Concours77]

“...I learned that knowledge does not equal understanding, and I learned that truth is truth. No matter what I think about it. So be very careful how you interpret things because you’re looking at the world with a bias whether you think you are or not...”

What is visible in the video looks like LOC, as defined for big jets. After many many views, I can say that what I see of the elevators, they are performing in sequence with the pitch. It is not a real clear video.

So the Pitch appears to be compliant with input. If I was following my bias, I might not enjoy reporting what I see, I would prefer to see upset due to turbulence. Anyone else match the elevators to response?

The best view is the first Nose Down, then just before the elevators disappear behind the wing, they move very Nose Up, and the a/c responds.

[ZeroOneTwo]

A weather related upset chasing the sudden speed loss, quick reactions and the engine exhaust is a good indication when the gas pedal was floored.

The Boeing windshear algorithm limits are quite conservative and the PFD indication should come up on the HUD....then just fly the FD.

A story less about a mismanaged approach and more about a good getaway. Hats off alround.

[fdr]

A weather related upset chasing the sudden speed loss, quick reactions and the engine exhaust is a good indication when the gas pedal was floored.

The Boeing windshear algorithm limits are quite conservative and the PFD indication should come up on the HUD....then just fly the FD.

A story less about a mismanaged approach and more about a good getaway. Hats off alround.



The original basis of reactive windshear is found in Proctor and Hinton's work on A Windshear Hazard Index, which can be found on NASA's NTRS. It incoporated a consideration on energy loss or gain rates, and also height above ground. The gain rate was included as what goes up, must come down etc... and that in the basic Fujita model of windshear, rapidly gaining energy is a predictor of bad things about to happen later.

https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20000116199.pdf

There are later patents that use additional sensor inputs to give an improved F Factor, whihc is the hazard index, and they include vertical g refer Woodell & Finley Predictive and Reactive Windshear Detection System and Method, US Patent 7557735B1 https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20000116199.pdf

On one of the nose overs, the bottom of the elevators is visible, thats a pretty large defection to be seen, would think that the pilot is in the loop on this, and attempting to maintain either aiming point/GS. Suddenly going above the GS from a semi stable condition all things being equal is the result of a rapid airspeed gain, (overshoot shear) that results in a following corrective pitch down to maintain path, and usually a rapid power change cycle, with a rapid reduction of power, followed by a return to a slightly higher power setting that existed before the shear entry, as the GS is lower, once the inertia of the aircraft has sorted out the IAS/GS steady state. The undershoot shear in itself is easier to handle, there are less steps in response to the changes. [Any comment on shear is for conditions that do not include microbursts etc, where the energy state of the aircraft can on occasion be defeated. Additionally, playing around with an off axis microburst penetration will find that the off axis vertical flow entry results in a pitch up, roll and yaw. The yaw can be significant, and if you pull into stall instead of respecting the PLI or stick shaker, you may have a wild ride from a stall with high yaw angles, and that will almost always give the commencement of departure towards autorotation]. A rapid series of gusts above and below steady state will get the crew working and there will always be a natural delay in the control inputs by the flight crew, they have to detect the change and then initiate a response. The detection has a delay, and the control system also has a delay. It would be correct to state that as an oscillation but it is not a derogatory use of the term, it is the physics of the control system that exists.

Narita is always fun to drive into, these are pretty interesting to look at but they would not have been the only aircraft going in there that day that had large pitch excursions. They handled it well, and did the right thing, twice. Now, whether the punters want the airlines to be operating in such conditions is a discussion between the pax and the airlines. I would think that rise was pretty much enough to get a line up at the next fear of flying seminars.

Watch those composites work!