Southwest Captain Reduced Power Before NYC Crash Landing
 

sure a lot of laughter

1000 foot call pretty close to on speed

Reading the group chairman's factual report she reduced thrust to idle at flaps 40, took control and decided the nose was too low for flaps 40 so pulled back to raise nose and added thrust as they impacted the runway.

When landing flaps 40 on a B737 reducing to idle before descent is stopped is always an absolute disaster unless you have a lot of excess airspeed.

bubbers is right.


I get the feeling she wasn't all there.

Not necessarily. If you are at bugged speed & commence the thrust reduction at about 30' to reach the idle stops by touchdown & flare the aircraft, you will get a smooth, nose high touchdown, as you should. If you carry the power into the flare & then chop it you will land very flat. If you are also too fast in this scenario, you will float & risk the possibility of a nose gear first touchdown (also know as wheel-barrowing.)

The main difference between flap 30 & 40 is that the flare needs to be more positive with flap 40 to get the nose high. To do that you need to have the power off & airspeed reducing towards Vref in order to prevent ballooning.

If you look at the FDR plots you'll see that 5 secs before touchdown/impact, with the co-pilot flying at nominal speed and slightly above GS, the captain calls out "I got it" and reduces thrust to idle but both pilots abandon the control columns !! and the pitch goes from +2 to -4 degrees pitch until touchdown/impact.

No movement in the 2 control columns: forwards, backwards, turning right, or left are recorded i.e. no motion !!

After impact the left engine throttle almost goes to full thrust for over 5 secs.

There seems to be no captain-side GS data on the plots.

Reducing toward VREF? In nil wind normally you should be at slightly less than VREF at the flare since the flare itself causes speed reduction naturally. If gust factors and HW component factors are added to the VREF which could be as much as 20 knots of additives, does that mean you will inevitably balloon? I don't think so. I would have thought it was pilot technique (skill) that prevents ballooning. Excess speed over VREF is a well known factor in one cause of ballooning but prevention is a pilot skill.

Having read the various reports and interviews I can't understand,as a layman, why the captain took control at this point.

If the plane hadn't touched down within the TDZ then a call of "go around" would surely be the procedure, assuming that the PF hadn't already commenced a GA.

Even a touchdown slightly beyond the last marker would still give approx 4000ft to stop, plenty for a 73G on a dry runway.

Only the Captain can really answer that.

My totally unfair speculations (but based on available NTSB data):

1. Prior to the approach, the Captain fixates on landing distances. This was due to some weather expected in the area (rain, tail winds during approach). The crew enters "wet" runway for their landing distance computations, and saw that the standard "Autobrake 2" setting isn't going to cut it. They set Autobrake 3, and the Captain also elects Flaps 40 for extra margin. This is her mindset coming in.

2. Near touchdown, the FO hand flies by reference to PAPI, while the Captain looks through her Heads-up Display (HUD) -- probably in IMC Mode, with ILS RWY 4 showing on the display.

3. The problem is, at LGA RWY 4, the ILS glideslope and the PAPI are not coincident. The PAPI is set "further down" the runway, so even if you fly perfectly down the PAPI, you would show increasingly high on the ILS GS. At the threshold, the airplane would be 54' high if on the ILS, but would be 76' high if on the PAPI. And we all know that the ILS by design gets really sensitive near the runway.

4. On short final the FO goes a touch high on the PAPI and is slow to correct it. He maintains the required descent angle (3.10 degrees), but on the Captain's HUD ILS it looks like the plane is "ballooning" when in fact it is not -- causing a type of spatial disorientation. In fact, from the HUD perspective, the plane looks like it's going to fly "well past" the TDZ -- where the ILS GS intersects the ground. (Which it was, since the PAPI is set further down the runway).

5. On the HUD ILS the plane looks like it's increasingly high and the Captain overreacts. She chops the throttle and takes over the controls from the FO, at less than 75' AGL. The ILS glideslope is now at full deflection too high (5-dots) -- even though the approach is fine on the PAPI. The Captain wants "to get down now", so she relaxes on the control column and lets the nose drop... and drop... and drop... chasing the already-past ILS glideslope.

6. Two seconds to impact, the Captain realizes her mistake. She starts to apply full-throttle but changes her mind -- and chops the throttles again to idle. BUT, she makes another mistake: the left engine throttle was not pulled back all the way. This creates a little asymmetric thrust.

7. The Captain thinks about pulling the nose up, but its already too late. Impact occurs with aircraft nose-down, no flare, and the nose wheel collapses. The plane is now sliding on the ground. Due to #6 above the plane starts to veer to the right of centerline. The Captain tries to adjust with rudder. Well into the slide someone notices the left throttle was still open and pulls it down to idle.

8. The plane finally comes to a stop. The Captain orders everyone to stay in their seats, but the flight attendants and jump-seat pilot notice smoke in the cabin. The Captain orders evac, but does not use the evac checklist.

Very Good
 

peekay4. That was a very good analysis.

That sure seems like a reasonable analysis to me. Those situations where the PAPI and the GS differ in close can sure make on path on one look like a float or tuck under on the other.

Like other cases of TMI (too much information) either path guidance will probably be fine to the touchdown zone on an ILS. And, often there is plenty of runway to land a little long or go around, but not enough to indecisively do parts of both maneuvers.

Is this maybe the video of the actual landing?

Good video. Notice how the nose pitches down before impact with descent rate not arrested first. The winglet trailing edge shows it best.

I never flew with a pilot that relied on papi, GS and HUD to flare so have a hard time understanding why just looking out the window and landing like we all did in my career isn't the norm for some pilots now. I'm sure it works in all aircraft still, no matter how many computers it has.

Peekay4 - your excellent analysis does shed more light on what went on.

I would be interested to know if crews would brief (at TOD) for any anomalies between the locations of the PAPI and the glide path transmitter.

Also if there is full deflection on the ILS (even if intentional) and PNF not happy at or near decision then surely a GA call is the most prudent course of action?

Video
 

There was another video posted in the original thread, however, the link has gone bad.

It showed the actual touchdown on the nose from a different angle than all the ones of the plane skidding down the runway.

If I can find it again, I will post. It shows the pitch down in the last moments.

Maybe someone here knows where that video is located?

I would be interested to know if crews would brief (at TOD) for any anomalies between the locations of the PAPI and the glide path transmitter.


Is it common on US charts for this information to be published? In EU it is normally the ILS TCH. Once again we might be having the debate about which glide path indicator is primary; ILS or PAPI. My own philosophy is if in doubt ILS. That's what an autopilot would fly on an auto land and it is checked/maintained to a higher fidelity; or so I've always been told/believed.
I remember BALPA Tech chap pies having a discuss over the use of HUD's. One point raised was how the non-HUD pilot could monitor what the HUD flying pilot was seeing and responding to. I assumed that a HUD displaying an ILS G.S. would match the basic PFD ILS G.S. Thus monitoring that parameter should be possible. Not so easy on a visual final with HUD displaying FPV to touchdown. The PM might have to use Mk.1 eyeball or PAPI; and therein lies a hole in the cheese. Thus are HUD's on a 2 crew civilian airliner necessarily a better/safer item?

ILS 4
 

The approach plate for the ILS 4 at KLGA has a statement that the VGSI and the ILS are not coincident. (VGSI angle 3.10 and TCH 76) The GS angle is 3.1 and the TCH is 54.

As an aside its a nice change to read an article that makes sense! Normally aviation issues are written about in terms that make no sense, but this one was quite good. Well done Bloomberg!

Both of them become less relevant the closer you get to the ground, they are designed to get you to 200 feet so that you can reference the runway. They stay in scan but become overly sensitive and so from DH in look at the Aim Point and make sure it stays in the same place up and down in the window, if there is an early trend seen from the approach aids make the correction by changing where the aircraft is pointing with respect to the aim point outside rather than chasing the needles or lights inside.

If the ILS and PAPIs are mismatched accept the picture delivered by the ILS at DH and hold it until the flare, it then wouldn't matter if the ILS and PAPIs both failed the approach angle would stay the same.

The Devil's in the Details
 

I've been following this for a while as I think it's an interesting case (thankfully no fatalities). Why on earth was there no call for a go-around??

There's a interesting footnote in the NSTB documentation that's just been released.

** after this point the captain received CRM training.

I am not a pilot, so apologise in advance if my comments do not make sense, but as a layman, I do not understand why a PM in this situation would take control at 400ft AGL before landing, surely this is a recipe for disaster?

According to the FCTM you shouldn't be less than VREF at the flare. The FCTM states "... maintain VREF plus the wind additive until approaching the flare. The steady headwind additive is bled off before touchdown while the gust correction is maintained until touchdown. Plan to touchdown at VREF plus the gust correction." So, in nil wind you should be at VREF + 5 until approaching the flare & then bleeding off the 5 kts to be at VREF at touchdown. Boeing do allow for the speed to drop below VREF prior to touchdown, as per the FCTM statement - "With proper airspeed control and thrust management, touchdown should occur at no less than VREF - 5 knots." So carrying extra speed to avoid touching down at less than VREF is also an incorrect technique.

Flying the aircraft the way Boeing recommends is not just fine in theory, but also works in practice as well.

I agree entirely. Miss-handling by over-rotation in the flare or snatching at it will generally lead to ballooning. However, in my experience, this is exacerbated by excess speed & those who have experienced this tend to compensate by flaring less & landing flat. Add to that the fact that most seem to be more concerned with being slow than fast & tend to carry excess speed, means that flat landings with the possibility of wheel-barrowing are common place, particularly at flap 40 which gives a more nose down attitude. I say that most are more concerned with being slow than fast because I observe pilots flying the approach above bug more often than on bug or below. And when 'speed" is called when required by SOP, they almost always automatically push the power up first, then look at the speed & correct.

My point was that if you are on the correct speed, reduce power at the correct point & rate, & then flare the aircraft properly, you will not bang it on at flap 40. And you will not land flat either.

Because she was a bad pilot and an even worse captain. That's the bare bodkin.

A sensible, and in the circumstances, reasonable question - but short answer, no it isn't.

Almost all Line and Training Captains take their responsibilities of ensuring FO's are given the maximum opportunities to not only fly to the limits of their abilities, and where safe, to also allow them to learn from their own mistakes. This means on occasions, an ideal descent path or approach may get stuffed up, but error recovery is an important learning aspect too. None of us are perfect, we all make mistakes, thankfully almost all are recoverable, and the only thing dented is a little pride, but along the way another learning point has been made that makes the individual a better/more experienced operator.

The last 1000' of an approach should be stable, but plenty of factors can upset the stability. In the last 100', which is normally covered in less than 10seconds, an on the ball Captain will be in monitoring overdrive when he is PM.
There are many things that I have seen both incompetent or inexperienced pilots do in the latter stages, that left unchecked could easily have returned the aircraft to kit form.

Clearly the closer one is to the ground, normally the more precise, direct and firm ones suggestions or orders become. Similarly static or dynamic weather and wind conditions play a factor in stability and your comfort/recovery zone.

However, there comes a point when a PF may be unable to process the suggestions or orders quick enough, and to try and do so may be counterproductive anyway and overload the PF.

By way of example, I have had to take control at 30' in the flare, at the same time as disabling the FO's inputs which were opposite to mine, on what was an otherwise excellent approach. There's just no time to have a chat about what he should be doing.

Therefore quite simply, any capable and efficient Captain, should know far he can let the FO go and still recover safely, before he takes over and lands.
The art of the equation is knowing the limiting factor of your own or the aircraft limits, to ensure as Captain, you take over before either have gone past a point of no return.

In this case, it would appear that she either let it go too far past her abilities, or she didn't display the correct skillset herself, possibly both. Either way it is a very disappointing read.
That a significant number of FO's would try to avoid flying with her speaks volumes, even if it doesn't pinpoint the why's. It's good the company gave her extra CRM training, perhaps more drastic measures were needed, but this is the luxury of hindsight.

Not sure what her Company culture was like with regard to go-arounds, but I have done many, a small percentage due to pilot error in not achieving a stabilized approach, and I have NEVER been queried by management at all.

If only either pilot had called it for what it was, and shot a second approach...

LTCX, I think you covered perfectly what a captain should be doing on every landing when he is PM. I too had to take control at 30 ft on a B737, flaps 40, when the FO selected idle power at Vref. Adding power saved the landing gear from going through the wing or at least causing significant damage.

That was the only time I physically had to take over an airliner from the PF because talking wasn't going to save the situation. Most of the time a bit of advice is all that is required.

I second what LongTimeInCX says about Captain's competence levels with regards late interventions. It's not easy, especially in the last 100ft, to intervene either verbally or physically. Will a firmly stated warning help or possibly overload a less able pilot?

I go back to the very basic cliches: a good landing usually follows a well-flown stable approach. In my experience as PM, I can normally tell quite soon after the PF disengages the automatics how they will perform the actual landing. But this impression is not foolproof and I've been caught out when a nicely flown approach didn't lead to a timely flare and I found myself gasping 'Flare!' at the last moment.

It's tricky. When an aircraft is descending at 12ft a second until the flare, you simply don't have much time and any intervention has to be carefully managed. I've not yet had to take controls on an approach, but I can only trust my instincts as a pilot to do so if the time arises when it doesn't feel right.

On the point of the FL40 landing flare, in my experience many inexperienced pilots do not flare correctly and land too flat. This is despite a commonly held understanding that the aircraft's nose is pitched lower when using FL40 as opposed to FL30. I regularly find pilots flaring to a point with very little positive pitch and then, when they find no immediate touchdown, they relax the flare. The subsequent landing is usually firm because of a loss of airspeed. Worse, it's very flat and nose wheel touchdown is very soon after the MLG meaning that you most certainly are not flying the nose wheel onto the runway, as you should.


PS: Most of you will remember this event: http://www.flightglobal.com/news/art...d-a320-320070/

Thank you LTCX, B44, MH152 - very clear explanations

I don't think there is an issue; I have seen plenty of SWA go-arounds during my various trips to the USA, quite a few off visual approaches to Chicago Midway, so I am guessing that, like with most airlines, GAs are encouraged rather than "pressing on" if any thing is amiss.

IF memory serves, the captain had not flown to LGA more than once, and then not as captain, prior to this adventure.

IF the captain had done nothing, the copilot probably would have come up with a normal or at least passable landing.


First off , lets dismiss any gender issues.

But I have flown with people who suddenly do not have the judgment/feel/perception of the plane that they should have. I have a theory about this.

Many years ago, I mean MANY. I read an article that said the human eye simply is not in the right focus after hours of flying at high altitude for ground ops. And so too the human mind. But that the time we spend in the approach phase of flight sort of reaclimates our being/eye/judgement to the low altitude stuff that is req'd for landing.

So, if you have been staring at a TV screen for hours at high altitude, you have to make a conscious transition for your eyes/mind to work for landing.


And this captain's mind did not make the transition.

She was worried about wx enroute/on apch. And probably had her mind overloaded upon seeing the environment near LGA (it can be impressive)...its like a really big city. I mean almost as big as New York (kidding boys and girls, I haven't lost my mind).


And then there is the water. Over running a runway into/onto the ground is one thing, but over running into the water is something else.

So there was a disconnect on many levels. And if you rarely use a certain flap setting, there is a further disconnect in visual cues, rumbles, engine sounds, throttle position that adds to the unease.

I would like to know if this particular captain had flown into other, shorter airports in large urban areas, (MDW) very often?


And what is with all the laughter on the CVR? Sometimes laughter is a coverup for fear. Fear heightens senses and sometimes makes for misjudgement.

Provided power is kept on almost to touchdown (note ALMOST), having MORE flaps should make a landing easier, not harder (lower speed for one).

I flew with one captain, once, about 18 years ago who had been taking a medication for weight loss. It operated by increasing the serotonin levels in the brain...making everything happy. Well, if everything is happy, nothing is wrong and judgement is off. The captain claimed that she had stopped taking the meds days before flying...BUT I think it may have taken more time to get back to normal.

COULD the captain involved have been on some, undeclared medicine, affecting judgement?

Glendalegoon. If the pilot had been taking SSRIs (selective serotonin reuptake inhibitors), then a few days off them is certainly not enough. I've been on them now for ten years, and the UKCAA will not allow their use, so no licence. I once tried going "cold turkey", and ended up having a psychotic episode. They have to be reduced SLOWLY (i.e. over a period of months), and with doctors monitoring the effect. Ironically, while on them I function fine, but rules is rules.

Huck - you nailed it.

But the FO isn't harmless. Boeing's written report shows how an increase in power took an airplane that was on a staple approach to a situation of trending high, long aimpoint, and shallow descent path that only achieved the required descent rate for a second or two after the a/p came off. The rest of the time the descent rate, path, or angle never achieved the parameter necessary to stop, let alone reverse, the divergent trend.

If you look at the last page or two of the FDR report (Section 18?) the voice overlay shows the CA making a callout at both one and two dots high on the GS, which is also four whites on the PAPI, about 'get it down'. The FO never corrects and the CA eventually intervenes but basically removes both pilots from flying the airplane.

So the CA intervened at poor flying and rapidly made it brutal. I can't call it 'brutal flying' because there was no flying done after 46' AGL. I'm surprised the FO's survival instincts didn't kick in and neither he, or the CA, made a last second attempt to arrest the descent rate.

We look at approximately 2.5 degrees nose up all the time on final. I can't imagine looking at zero, or negative pitch attitudes, at such a low altitude when the expected input is steady or increasing pitch attitude.

For this specific runway (LGA RWY 4), two-dots high on the GS is not four whites on the PAPI, due the GS and PAPI not being coincident, as discussed in the previous page. (And why the FO is slow to correct).

In fact at the runway threshold, even a full-UP deflection on the ILS GS would be well below the normal PAPI glide path!

We can calculate that for this runway, a full-up ILS GS deflection (3.8 degrees) at the threshold is 66 ft AGL, well below the PAPI TCH -- three reds! -- and just 3 ft above four-reds (at 63 ft).

A pilot flying the ILS right on the GS would see four-reds on the PAPI just prior to touchdown:

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

Now now now, how can you say that! I think there will be supremacists who will swear on their great great great grandfather's graves that all pilots west of the Urals are the very best, perfect in every way.:ok: Incoming.....

There are lots of issues discussed here. Firstly, if I was PIC and let it be known I was nervous about an approach due to various factors, then I AS CAPTAIN WOULD FLY IT. That's one reason I am paid a few bucks extra. 2nd. There is talk about letting an F/O go so far and then let them learn from their errors, even take over. I applaud that; but: not all line captains are top notch; not all are LTC's. They do not have the competence to make such judgements. In the modern LoCo world there are captains with 3000 trained monkey hours. Do not expect them to have the skill, judgement, awareness to make such discussions. They will be out of their depth.
Back to my first point. Sorry mate, but this one's mine.

Yet the only warning on the approach plates is:

"VGSI and RNAV glidepath not coincident (VGSI Angle 3.10/TCH 76.)"

Surely, an approach where there is a gross difference between VGSI and ILS/RNP approaches should be highlighted a little more than a throw away comment? Perhaps:

"WARNING - DISPLACED VISUAL THRESHOLD -
Glidepath on ILS will be shown 4 Reds by PAPI -
2 Red 2 White on PAPI will show as well above glidepath on ILS"

This would alert the crews to brief the PM prior to TOD that a panic reaction is NOT required if there is a mismatch ILS to VGSI

Misd-again - a pitch angle of +0 is normal on approach for Flap 40 on a 737.

Ian W: Are you suggesting there is more than 'Pilot error' at stake here? Perhaps you are correct. I remember in the Cali B757 crash some blame was attached to the FMC supplier. Personally I did not agree with that and thought it a red herring. However, in this case, you might have a valid point; the crew were ill-informed, perhaps.

Jwscud - thanks for the correction. 1.0 for F30, zero for F40.

Boeing's written analysis of the GS/PAPI deviation -






Document 2 Materials Laboratory 15 - Factual Report 13-062 (with 6 embedded images) Filing Date August 27, 2013 5 page(s) of Image (PDF or TIFF) 0 Photos


Based on the glideslope intercept guidance, at 250 feet geometric altitude (3800 feet


prior to the runway threshold), the airplane was slightly below the glideslope beam


(Figure 5). As the descent continued, the airplane passed through the beam at 145


feet geometric altitude (1650 feet prior to the runway threshold) and began to deviate


above the beam. The airplane continued to deviate above the beam and passed


through the 1-dot high profile at approximately 125 feet geometric altitude (1050 feet


prior to the runway threshold), and passed through the 2-dot high profile at 115 feet


geometric altitude (650 feet prior to the runway threshold). Based on the PAPI


intercept guidance, at 250 feet geometric altitude (3700 feet prior to the runway


threshold), the pilot’s eye was below the approach path. As the descent continued, the


pilot’s eye passed through the approach path at 130 feet geometric altitude (1000 feet


prior to the runway threshold) and began to deviate above the nominal approach


path. The airplane continued to deviate above the approach path, and the crew would


have received the slightly high (3 white/1 red) visual PAPI cue at 120 feet


geometric altitude (650 feet prior to the runway threshold) and would have


received the high (4 white/0 red) visual PAPI cue at 105 feet geometric altitude


(200 feet prior to the runway threshold). At the runway threshold, both the glideslope


deviation and PAPI visual guidance indicated that the airplane was high. The airplane


was following a 2.1-degree glide path from approximately 1400 feet prior to the


runway threshold to touchdown and was high on the approach. Touchdown occurred


at 1425 feet beyond the runway threshold on the runway centerline

@RAT 5

I think different captains will have different opinions about this, depending on why they're nervous about the approach.

Sometimes when you're PF on a "tricky" approach (or even a non-precision approach), you are too busy with the mechanics of flying to think about "the big picture".

So many captains would actually prefer the co-pilot to fly the approach, so they can concentrate on the safety aspects of the flight.

Other pilots would undoubtedly have a different philosophy. But sometimes being a good "commander" means knowing when to delegate aspects of the flight to others.