Ask The Pilot

[AviatorInsight]

Have fun with that. Whilst I expect that the flying in low vis is always done by the captain, good support makes a huge difference. It’s simple enough when it’s working, but of course, you only ever see that once or twice in the sim.

Yeah thanks. It is all done by the captain but 17 approaches and 2 to be checked out at 0400 on a Sunday morning...that’s a lot of LAND 3 rollout flare armed.

 

[mikenz]

Is it possible to extend flaps or gears at cruise speed?

 

[QF WP]

I guess the engine in this clip should be (has already been) put to idle...

https://www.facebook.com/video.php?v=354133535518923

Story here: Plane engine part comes loose in mid-air, flight forced to make emergency landing

 

[eric2011]

Is it possible to extend flaps or gears at cruise speed?

Without ripping essential stuff off....

 

[jb747]

Is it possible to extend flaps or gears at cruise speed?

Without ripping essential stuff off....

In a word. No.

Everything has speed limits. The gear is pretty strong, but the doors certainly aren't. At a minimum, I'd expect to lose at least some of the gear doors. Who knows how the hydraulic piping would fare. Badly, I'd expect.

If the question is in relation to depressurisation, you don't need the gear. If you do want it, you'll need to maintain level until you slow below the gear limit...and that's more time spent at altitude. When I first flew the 747 Classic, it was still procedure to do just that, but by the 400 turned up they'd worked out that it wasn't any quicker, and actually involved more time at the dangerous altitudes.

 

[jb747]

I guess the engine in this clip should be (has already been) put to idle...

Story here: Plane engine part comes loose in mid-air, flight forced to make emergency landing

Pretty unusual failure. I'd expect the engine is a actually shut down, and is just windmilling. You don't expect to have something as large as the spinner just bouncing around in there.

 

[AviatorInsight]

Is it possible to extend flaps or gears at cruise speed?

It’s possible yes, but there will be some damage to the flaps. Limitation to take flap 1-5 (737) is 250kts below FL200.

The landing gear is actually possible to be extended at cruise 270kts/0.82M. Once extended you can actually speed up to 320kts/0.82M. Perfect for depressurisation situations. To retract it again if you wanted to for performance, you would need to slow up to 235kts.

 

[jb747]

I just realised that I didn't mention flaps. They are generally speed limited, but also altitude limited. Basically they change the shape of the wing, from a high speed to a low speed device. A low speed wing, flying at a high mach number (cruise) is pretty will instantly going to give you areas that have a transonic flow, and you'll get strong shock wave formation. Ignoring any structural damage, that could lead to pretty well instant loss of control, depending upon the location of the shock.

 

[Saab34]

The PNG 737 Crash final report has been released with the associated engineers video from the Jump Seat.

http://www.aic.gov.pg/pdf/FinRpts/2019/AIC%2018-1004%20P2-PXE/Annexed%20Video.mp4

I assume below profile under 500ft with a dozen warning calls a go around would be expected in such a powerful machine? Quite an ugly video.

 

[jb747]

The PNG 737 Crash final report has been released with the associated engineers video from the Jump Seat.

http://www.aic.gov.pg/pdf/FinRpts/2019/AIC%2018-1004%20P2-PXE/Annexed%20Video.mp4

I assume below profile under 500ft with a dozen warning calls a go around would be expected in such a powerful machine? Quite an ugly video.

Interesting video. I'm sure AV will fill in some blanks for us. There are lots of things that I'm seeing that I don't like. -5º of pitch is just terrible. An approach is flown about 2.5-3º nose up. Corrections rarely require more than a change of 2º. That's a change of 7-8º....towards the ground.

I don't understand what modes they have the AP and then FD in. Nothing is being displayed for VNAV/pitch.

Their visual contact seems pretty tenuous...so below the MDA, that's a cause for a go around. You don't attempt to fix a 'PULL UP' warning. There is a response to that which will keep you safe...they did not do that. There was never any response to any of the glide slope calls. That can actually be ignored in some restricted circumstances...but it does require you to actually be visual. The approach has a start point at 2500', and not below. That would have set the aircraft up to be on a stable 3º descent path. He's ignored that, and is low for virtually the entire approach.

The end result isn't all that surprising...

 

[Saab34]

Major culture issues inside this operation from what I’ve been told. Aussie FO and Local Skipper involved here.

I’m also led to believe the local skipper is still employed

 

[jb747]

Major culture issues inside this operation from what I’ve been told. Aussie FO and Local Skipper involved here.

Well, if he's a local, his arm is a lighter shade than the blokes I've met. There may well be cultural issues, but I think I'll wait for the report to come out on that one. I'm pretty certain an equivalent video of some of EK's (I'll pick on them today) arrivals in JFK and Moscow would be every bit as horrifying.

I’m also led to believe the local skipper is still employed

My absolute pet hate is airlines that fix any problem by firing the pilots. This is also a failure of their training and checking systems at the very least. The pilot is simply the end result of that. So, let's fire the head of training, and every sim instructor and line instructor that the pilot ever flew with. That'll fix the problem. In no way. That is the fix employed by any number of airlines, but it does nothing to fix the deeper issues.

 

[AviatorInsight]

The PNG 737 Crash final report has been released with the associated engineers video from the Jump Seat.

http://www.aic.gov.pg/pdf/FinRpts/2019/AIC%2018-1004%20P2-PXE/Annexed%20Video.mp4

I assume below profile under 500ft with a dozen warning calls a go around would be expected in such a powerful machine? Quite an ugly video.

Definitely ugly. It all fell apart around the minimums call. I had to replay this to watch the actual footage as I wasn't quite sure what was going on with the animated annunciations. So the Capt was definitely the PF as CMD A was selected. The actual annunciation on the PFD is just CMD so the addition of the A would've been to show the left autopilot was engaged. This approach is typical of an RNAV approach. For some reason it's not displayed on the animation but VNAV was definitely selected. It should have been in VNAV PTH (path). LNAV was also engaged and armed (shown by white) for the go around. FMC SPD is exactly that. The commanded speed in the FMC. So far so good.

Now this is where it gets interesting. At 750ft (their minima) a few things happen:
1. on the nav display in the actual footage the magenta line makes a sharp left turn. To me this seems like the missed approach path.
2. I agree their visual segment is sketchy at best.
3. They forgot to move their altitude selector to the missed approach altitude. At this point the autopilot captures the altitude and now things start to unravel quickly. When they move it up to 2500ft VNAV now disengages and it reverts to control wheel steering in pitch.
4. As they pass over the final waypoint without pushing TO/GA LNAV now disengages.
5. FMC SPD reverts back to MCP SPD and is basically giving speed control back to the pilots.
6. The captain realises now that he's getting high, disengages the A/P and the annunciator reverts to FD (flight director is giving the commands as per what has been set on mode control panel) and really over compensates.
7. The fact that they had the G/S aural alert go off means that the ILS was being masked behind the RNAV approach but at no point was it armed on localiser or glide slope intercept.
8. With the change in pitch the capt gets fast and is more concentrated on speed. The thrust comes close to idle but barely recovers.

This was a clear case of loss of situational awareness.

 

[jb747]

This is the full report for the PNG accident. It makes eye watering reading. Note what it says about the same crew's previous approach.

http://www.aic.gov.pg/pdf/FinRpts/2019/AIC%2018-1004%20P2-PXE/P2-PXE%20AIC%2018-1004%20Final%20Report.pdf

 

[tgh]

ot.. but as a kid I had access to the aviation safety digests published by the then Dept of Civil Aviation.
I recall a primary cause of endless light aircraft accidents and incidents was .. drum roll…..loss of situational awareness.
Interesting that such a well studied phenomena is still alive and well today.

add.. even today.. old asd's could make informative reading as aviation was very different in those days ..

 

[jb747]

ot.. but as a kid I had access to the aviation safety digests published by the then Dept of Civil Aviation.
I recall a primary cause of endless light aircraft accidents and incidents was .. drum roll…..loss of situational awareness.
Interesting that such a well studied phenomena is still alive and well today.

add.. even today.. old asd's could make informative reading as aviation was very different in those days ..

Loss of situational awareness happens at all levels. The more you train, the more you can push it into the background. But, it will come back to the front with fatigue, automation issues, complacency, etc. It's one reason why it should be so much safer with two pilots...hopefully one retains the bigger picture. The breakdown in procedures that happened here is astounding, but not at all unusual.

The lack of awareness behind the MCAS debacle shows that it's not something confined to the pilot world.

 

[RooFlyer]

One thing that is notable for me is how well the aircraft survived the unexpected water landing. After US1549, we heard all about the difficulties of landing on water, dangers of engines being ripped off, cartwheeling etc.

I'm not doubting that, but these guys seemed to have ploughed into the water, oblivious, yet the aircraft sorta survived (report says most 'pull apart' damage occurred after sinking) and even the nose gear remained attached. Dead calm lagoon water obviously helped, but was this a 'miracle' or do we learn that the aircraft is a bit more robust than previously thought?

 

[Quickstatus]

@jb747 @AviatorInsight

The report mentions communication between the pilots and (I presume) SFO ATC (??). What radio is used for such long range communications

 

[flyer89]

There seems to be so much wrong with this incident. Not adhering to the SOP’s, almost no application of CRM and systemic issues with training. Holes in the cheese.....

 

[jb747]

The report mentions communication between the pilots and (I presume) SFO ATC (??). What radio is used for such long range communications

There's most likely a VHF to satellite link on the island. So, you talk on VHF, and it's retransmitted to SFO and back.