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-   -   Southwest Captain Reduced Power Before NYC Crash Landing (https://www.pprune.org/rumours-news/550210-southwest-captain-reduced-power-before-nyc-crash-landing.html)

framer 2nd Nov 2014 22:13

I think there will be a few different things at play here. The things that stand out to me are;
1/ There was a lot of 'instruction' from the Captain during the approach about energy management so either the F/O was still learning how to manage the aircraft through the automatics, or the Captain was a bit nervy and micro-managing the F/O as he tried to do his job. I'm not sure which.
2/ There was a lack of discipline shown by both pilots during the approach with regard to how they communicated, it was very relaxed with extra banter. That worked ok when there was no time pressure but when clear decisive SOP's based communication was essential due to time constraints......they weren't in the habit and couldn't communicate clearly.
3/ The. Captain and the F/O were using different references for glide path control. This shouldn't really be a problem, the Captain should look at the approach and decide if it is acceptable to her or not. If it is, continue, if it is not, go around. Why try to salvage it so close to the ground? The difference between glideslope and PAPI may have been a contributor to the situation at 200ft but it was poor decision making and communication by the Captain that placed pressure on her technical skills which were found to be lacking in that circumstance.
In my mind it is a clear case of weak non- tech skills placing pressure on tech skills.

peekay4 2nd Nov 2014 23:25

@misd-agin

Yes, you can see in the detailed Boeing charts (page 5 of the chart supplement) that at 1-dot high GS, the PAPI was on path (two whites, two reds).

As the plane reached 2-dot high GS, the PAPI became slightly high (three whites, one red). At this point the PAPI deviation was only 0.16 degrees. This is consistent with that the co-pilot reported.

The co-pilot was slow to correct and allowed the PAPI to reach four-whites, some 400 ft after that point. I believe the GS was at full-deflection as this point (there's some discrepancy in the Boeing data).

RAT 5 3rd Nov 2014 07:29

Peekay 4. I understand your thinking and have operated with monitored approaches: if that is what you are alluding to. Normally, if I would want to see the big picture, I would indeed become PM, but the PF would most likely fly an autopilot controlled approach. Whether I or the F/O would land might depend on SOP's or the situation at the time. I agree with your comments about 'being a good commander'.
In this scenario, if the autopilot had been flying the ILS they would not have flown an erroneous glide path angle to a long touch down. If there was some nervousness about the approach, the weather conditions and the shortness of the ray, then why make a difficult job more so by manual flying. Being a good pilot also means using the best aids and techniques that the current situation requires. There are days to fly manual and days to fly automatic to DA. Perhaps this was one of those.

FullWings 3rd Nov 2014 07:46

Can anyone give an explanation as to why the ILS GP and the PAPIs at LGA were set differently? This is not the only airport in the world where it’s like this.

I know it was on the charts but it could lead to a kind of cognitive dissonance in an individual and a CRM breakdown with multi-crew, where one pilot is on the ILS and the other on the lights (or even just going visually for the TDZ). Yes, you can and should brief these points but sometimes it feels that things are being made more difficult just for the sake of it. A note saying “Last 300m of RWY 24 made of blancmange” is useful, but why the blancmange in the first place?

I flew into KSAN recently and noted that the approach gradient and the PAPI angle have been aligned with each other since my last visit. Hooray for common sense!

McNugget 3rd Nov 2014 08:08

Fullwings
 
Yes, it's not the ideal picture, seeing yourself on ILS glide path, but high on PAPIs.

The reason is due to the geometry of touchdown aiming point vs ILS receiver and pilots eye height. The PAPIs can only truly coincide with he ILS all the way down at one set aircraft eye height. I believe, at international airports , that's set, presumably, based on the most common types at the airport. Thus, if you're in an aircraft with a higher eye height than the PAPIs are calibrated to, you'll be 3 whites low down, whilst being on ILS glide path.

It's not ideal, but the answer is you follow the most accurate indication - in this instance, the ILS. Of course, the correct technique is to fly visually during the final stages, which isn't helped by the fact that you can still see the PAPIs. It is quite common for new pilots in large aircraft to dive to meet the PAPIs in the last hundred feel, which in turn, destabilises the approach.

Mikehotel152 3rd Nov 2014 08:30

McNugget's quite right, but in some parts of the world PAPIs on each side of the runway don't align, let alone with the G/S! Without local knowledge you will be surprised on short final.

Even in supposedly well-managed places there are discrepancies but this is presumably intentional due to the differing technical/legal requirements of obstacle clearance limits when designing precision vs non-precision or visual approaches?

FullWings 3rd Nov 2014 10:13


The reason is due to the geometry of touchdown aiming point vs ILS receiver and pilots eye height.
I was thinking more of those places where the actual glideslopes are set at different angles, visual vs. electronic.


Even in supposedly well-managed places there are discrepancies but this is presumably intentional due to the differing technical/legal requirements of obstacle clearance limits when designing precision vs non-precision or visual approaches?
Well, that was what was in my mind when I asked the question but it would be interesting to have some concrete examples.

Surely it would be better to just set all glideslopes for a particular runway to the same, e.g. the minimum required to give obstacle clearance, etc. using any of the means of guidance? Would save a lot of head scratching and possibly aircraft, as in the accident we’re discussing...

Old Boeing Driver 3rd Nov 2014 12:19

Flight paths
 
Both the PAPI and the GS are both 3.1 degrees at KLGA according to the approach plate.

The PAPI has a TCH of 76' and the GS has a TCH of 54'

peekay4 3rd Nov 2014 15:16

On non-precision approaches one can see big differences between the PAPI angle and the vertical descent angle. E.g., at Greenwood Lake Airport (4N1) RNAV (GPS) RWY 6, the descent angle is 3.15 degrees/TCH 40 but the PAPI is at a very steep 5.75 degrees/TCH 39.

The FAA Order 8260-19, Flight Procedures and Airspace, gives this guidance: "n. VGSI and IAP glide path angles/vertical descent angles should be coincidental (angles within 0.2 degrees and TCH values within 3ft)." Otherwise the difference must be charted.

In reality, it's quite common for the PAPI and the ILS to be non-coincident; that's not a problem in itself.

As McNugget mentions, PAPI designers must consider different eye-to-wheel heights. A 747 might have an eye-height of 45 ft, while on a 737 the eye-height is around 20 ft. Thus a PAPI will be "more coincident" for some aircraft than others.

At large airports, they will put the PAPI further down the runway to accommodate the 747s. If you use the PAPI on a Dash-8 (11 ft eye-height) to the flare, then you will land on the long side.

The possible issue is when two pilots of a crew use different references (PAPI vs GS) and the plane's eye-height is very different from the design eye-height. Plus in the case of this crash, the cues provided by the HUD might be of a further factor.

In Canada at least, you can find out the design eye-height for a PAPI in the charts (coded as P1, P2 and P3). The design heights are: P1, <= 10ft. P2, <= 25ft. P3, <= 45ft.

alph2z 7th Nov 2014 19:45

Nobody seems to talk about the fact that both pilots abandoned their respective control columns for over 5 secs just prior to the crash.

Semaphore Sam 7th Nov 2014 22:45

Well, it seems obvious, to me at least, that if the SIC is flying the approach, and the PIC says "I have it", the duty of the SIC is to relinquish control, and to assume the Pilot Monitoring duties. That's not 'abandonment', it's giving up control, which is proper. What's the issue? Sam

westhawk 8th Nov 2014 02:39

From the information given so far, it appears possible that a proper transfer of control between the two pilots may not have occurred as it should. How much if any this may have contributed to the outcome is yet to be established. Other factors not yet fully considered may have contributed as well.

For line pilots the following explanation is quite unnecessary. Others may find it worth consideration though.

When one pilot assumes control of an airplane from the other pilot there is a transfer of control protocol which should be adhered to. Most airlines and other operators of multi-crew aircraft have their own written SOP containing a specific series of words and actions to assure that a proper transfer of control takes place. (the following assumes that the autopilot is not engaged)

Representative examples of a "Positive transfer of control" SOP would contain language to the effect of: Pilot assuming control clearly announces "My airplane" or "I have control" while placing their hands on the flight controls. The pilot being relieved of control verifies that the other pilot is on the controls, then releases control and states "Your airplane" or "You have control".

Exact wording of the SOP will of course vary somewhat between operators but some method of assuring that someone has control is necessary!

TowerDog 8th Nov 2014 04:28





From the information given so far, it appears possible that a proper transfer of control between the two pilots may not have occurred as it should. How much if any this may have contributed to the outcome is yet to be established
About 100%, established or not..:sad:

Uplinker 8th Nov 2014 07:16

Having read the full CVR transcript, my overall impression is that the approach was poorly briefed, in particular with regard to the weather. The Captain seemed to be behind the aircraft, and not in command - reacting instead of thinking ahead. She had very poor situational awareness, and her monitoring calls were non-standard and too vague. A go-around, (which was not briefed), should have been called. In fact, there is very little evidence on the transcript of any briefing about which runway, which approach facility, what its frequency and identifier was, and which other navigational aids etc. would be used. There seemed to be confusion between the pilots as to how some of the aircraft systems operated. The F/O was getting overloaded, as you can see because there are times when he just mindlessly repeats a word the Captain uses, just to be saying something, but seemingly without any spare capacity to say or do anything else.

A slightly pedantic point, but I believe this is also an illustration of why one should use the correct terminology.

Had the Captain used the correct SOP call for their airline at very short finals, both pilots would have known without doubt what was happening, i.e. a complete transfer of control was intended.

It seems that the F/O thought the Captain intended to take full control, but perhaps the Captain only meant to "help" with the throttles - she was worried about the aircraft speed in the latter stages - and not the control column too.

I don't want to get into a USA bashing here, but having just returned from a UK-Florida flight; ATC RT calls in the USA seem to have departed from standard by quite a large degree. Normally, everyone gets the message correctly, but sometimes things can turn around and bite you in the a**e. Standard RT language does sound very anal, (and 'British'), but it is designed for a reason. Some pilots try to sound very slick and - in their minds - professional by using slang and cod phrases, but beware. In particular the number of times one hears call-signs and next frequencies missed is amazing. Calls like "Center-southwest-twenty-twenty-five-out-of-two-five-oh-comin'-down-eighteen-thousand-thirty-twenty-seven-smooth", (spoken rapidly like an auctioneer), are very common. They sound slick, confident and clever, but can give rise to confusions and extra read-backs when things start getting busy or difficult.

The transcript of this approach shows that all users are trying to be very slick with made-up phrases such as "Tower's on eighteen seven". The weather avoidance calls should be something like "Requesting right turn, heading xxx to avoid weather", but instead there is: "We uh.... we just need to cheat a little right here".

I will probably get flamed now, but I reckon this sort of slang phraseology both between plane and ATC and pilot to pilot can cause confusions - and extra workload - to occur.

ExSp33db1rd 8th Nov 2014 07:35


..........Most of the time a bit of advice is all that is required.
Like ... everything's fine, only you can stuff it up now !

RAT 5 8th Nov 2014 15:39

I read Uplinker's 1st paragraph and make the observation, again, that if there was such nervousness about this approach then who-ever was chosen to fly it, and there are different opinions as to whether this would better have been a captain's approach or a monitored approach, might have been more sensible and used the autopilot & autothrottle. This would have ensured the a/c reached MDA on speed and on the correct glide path. This accident occurred because, ultimately, both these parameters were not correct and confusion and mishandling ensued. There are times for manual skills to be used and times not. Making the sensible choice is part of a commander's duties. IMHO

westhawk 8th Nov 2014 17:44


About 100%, established or not
There are a multitude of factors contributing to the event. The last minute transfer of control was caused by or related to the perceptions and actions preceding. The overall role of each of those perceptions and actions will be the subject of much analysis. I deliberately used permissive and non-conclusive language in my above post in recognition of the fact that this process is continuing. Or should everyone including the NTSB just accept the crowd consensus that she was a bad Captain and be done with it? [/sarcasm] :cool:

glendalegoon 8th Nov 2014 18:37

Uplinker is correct.


Radio useage in the USA can go from perfect, to perfectly awful. Slick guys are the worst.

About 24 years ago I was saying "FIFE", and "TREE" on the radio for 5 and 3 and it was just like the "BOOK" said. My captain got very upset and told me not to use these terms. When I made captain I went back to the correct way.

I will make this short and sweet. The captain was not very good, and was having a bad day. In other words if you are good and having a bad day you might be average. If you are not very good and having a bad day, you drop well below average.


I firmly believe that some brains are not well designed for being a pilot. perhaps the brain in question fell short.

I also wonder how I landed for years at LGA without a HUD, or without breaking off the landing gear.

I think we can all be happy about one thing, if this captain had been flying the Long Island Expressway Visual approach, the results would have been much worse.

;)

misd-agin 8th Nov 2014 19:03

Ultimately it wasn't the lack of Captain skills that caused the accident. It was the lack of flying skills, and 737 flying skills even with 12,000(?) hrs in type, that caused the accident.

At a certain point, distance or altitude a plane stabilized with appropriate power setting and in trim will still land at an acceptable sink rate even with no pilot inputs. AA 612, Lax-EWR Nov 21, 1987, is an example of that when the CA had a fatal heart attack at approx 50'.

This accident showed that going to idle at 46' with flaps 40 and then not controlling the pitch attitude is unacceptable in a 737. That should be covered in initial simulator training or IOE/LOE and shouldn't surprise a pilot with 12,000(?) hrs in type.

captjns 8th Nov 2014 19:27


I also wonder how I landed for years at LGA without a HUD, or without breaking off the landing gear.
Give me that beautiful River Approach to RWY13 or the Prospect Visual Approach to RWY31 in my B727 anytime.:ok: We don't need no stinking HUDs:mad:


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