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PIA A-320 crash in Karachi

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Could false glideslope be contributing factor in the initial established situation?

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17 minutes ago, him225 said:

Could false glideslope be contributing factor in the initial established situation?

Nope. Even if there was a bounced false glideslope signal, there are so many other visual, audio and instrument reading clues to indicate that you are not on the glideslope when flying in the envelope those guys were in, that you'd have to be deaf and blind to miss them and just go: 'well, I know we've got all these warnings and alerts going off skipper, and the gear won't come down because we're so fast, but the PFD needle says we're in the pipe five by five, so let's go for a landing shall we?'

One of the many reasons you don't dive down on a glideslope signal, but instead fly into it from underneath when you're nice and stable, is because you'd be chasing a descending signal and this can mean you might pick up a bounced signal. This is why you don't do it.

If you're five or six miles from the runway threshold at well over twice the height you should be, and getting close to 100 knots over the speed you should be, it doesn't matter if the glideslop needles are saying 'yeah, you're good mate', you know that's a false reading. There is no mistaking the sight picture out of the window which shows no sky whatsoever because you are in a steep dive, nor is there any mistaking the alarms which are sounding, and the ECAM messages allied to those alarms, which are telling you that you are going so fast that your landing gear is not going to deploy.

We need to wait for the investigation to confirm everything which was going on, but even a novice pilot can see that this was not the way you go about landing an aeroplane, and certainly not when you are a professional pilot with the responsibility for the safety of many lives. At this point with the information that we have, it really does look like there is no excuse for the actions of the crew.

Edited by Chock
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53 minutes ago, Chock said:

..there is no excuse for the actions of the crew.

...getthere-itis...Company finance policy of "thou shalt never go-around due to the extra costs". "Gee, ma I can hot-dog this FBW 'Bus no problem... oops.."


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Here's a speed and altitude graph of flight 8303. As assumed, speed was all over the place the whole time. They were doing around 210 knots over the runway threshold when they should have been at approach speed in the 130-140 knots region.

It also shows that the aircraft was never really above the speed limit for gear extension (260 knots according to FCOM, 250 knots according the placard in the cockpit) under FL100 so it seems to dismiss the theory of the gear being prevented from extending due to speed. There's another theory that the gear didn't come down even when the aircraft slowed to below the extension speed limit because you would have to recycle the gear lever from down to up and back to down to disable the safety valve which prevents gear extension above 260 knots. I've since read reports of A320 drivers though that from their experience you don't have to recycle it as the safety valve will automatically open once the airspeed drops below 260 kts. System schematics in the A320 FCOM suggest no need to recycle the lever either. So there has to be a different reason why the gear wasn't down as reported, or the reports are wrong and it was in fact down and prematurely retracted upon go-around. FDR data needed.

PK8303-Altitude-and-IAS.png

While I'm at it, here's another one which shows the altitude profile of flight 8303 compared to a normal A320 approach into 25L at the airport.

20200522-0-G-1.jpg

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Curious why the pilot continued down to airport level at 210kts, he must have felt even before crossing the airport boundary he wouldn't be able to reach near normal landing speed by the touchdown zone?

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Although not very likely, it is worth bearing in mind the admittedly remote possibility that the aircraft's transponder was sending erroneous data and therefore plots we have of speed and altitude are incorrect. Since there are two military bases nearby, I assume the investigators could check this against radar plots if they thought it was a possibility. Seems a remote chance, but everything needs looking at because something definitely went really wrong on this flight, and it is just possible that it was not entirely the crew's fault until we have absolute proof that it was.

Remember, in most countries - with one or two exceptions, where there is an automatic criminal investigation opened, which proceeds concurrently with the relevant AAIB's efforts (and often gets in the way if history is anything to go by) - that it is not the job of an air accident investigation board to apportion blame; it is the job of an AAIB to determine what happened; it's then up to other authorities to determine if further legal proceedings should occur in regards to blame.

Edited by Chock
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4 hours ago, him225 said:

Curious why the pilot continued down to airport level at 210kts, he must have felt even before crossing the airport boundary he wouldn't be able to reach near normal landing speed by the touchdown zone?

I think everyone right now is curious as to why the approach went as far south as it did. You're supposed to keep the planned approach speed for the entire final approach and not just reach it once touching down.

3 hours ago, Chock said:

Although not very likely, it is worth bearing in mind the admittedly remote possibility that the aircraft's transponder was sending erroneous data and therefore plots we have of speed and altitude are incorrect.

Good point. However, the PM did relay to ATC they were at 3500 ft at 5 miles out and even said they were "comfortable now" on the ILS when 3500 ft at 5 miles out is nowhere near anything which might be considered to be comfortable on an approach. Plus, the controller seemed to be aware of the high altitude as well. So the ATC recording indicates a highly unstable approach as well.


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Another possible contributing factor: they likely had spoilers extended the whole steep final approach, and may have forgot to retract when going around not realizing until they drag on the runway, since rarely you have spoilers out when nearing touchdown and so perhaps not part of SOP.

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Where they leaving Cruise altitude later than planned or what made them being so high on profile in the first place? That profile posted by @threegreen could be directly from FSX multiplayer sessions....yikes.


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5 hours ago, SAS443 said:

Why're they leaving Cruise altitude later than planned or what made them being so high on profile in the first place?

That puzzled me too. We all know a good landing starts with a good approach, so a good approach starts with a timely descent, and a timely descent starts with some good planning while in cruise. I guess that is why we should be grateful more modern FDRs and CVRs can record much longer periods of data these days than used to be the case; it will be interesting to hear what the plan/briefing was (assuming these things even existed).


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10 hours ago, SAS443 said:

Where they leaving Cruise altitude later than planned or what made them being so high on profile in the first place? That profile posted by @threegreen could be directly from FSX multiplayer sessions....yikes.

It’s not uncommon at all to get close to an approach and be higher than you’d like, for numerous reasons. It could be ATC left you hanging, it could be we didn’t boogey down fast enough or early enough. It could be because of weather, crossing limitations on an arrival, etc. In my current ride,  F900ez, descents are the most demanding maneuver because the word not allowed plane will just not slow down. We almost always have the speed brakes out descending for an approach, unless we really plan early and get ATC to cooperate and let us down earlier than they usually do. All part of piloting, you need to know your plane and what it can, and can’t do. These guys knew neither it seems.

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2 hours ago, Rbass said:

These guys knew neither it seems.

What's puzzling is that these pilots were both experienced with lots of hours. And this still happened when any flight student, in fact anyone who knows something about flying an airplane, would recognize that approach is not a good one and it's not going to work.


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49 minutes ago, threegreen said:

What's puzzling is that these pilots were both experienced with lots of hours. And this still happened when any flight student, in fact anyone who knows something about flying an airplane, would recognize that approach is not a good one and it's not going to work.

One thing you learn very fast is that hours logged is not a good indicator of skill or attitude. One thousand hours or one hour a thousand times over. Mental attitude is everything, and some pilots just don’t have it. The best pilots are not the ones who make greaser landings every time, they’re the ones who make flights look boring and routine because their awareness and decision making are always waaaaaaaay ahead of the trip. These guys usually also make good landings most of the time too though. These two particular guys, were both totally oblivious to their situation, no matter how many hours they said they had. The best thing we can do is not evaluate pilots based on hours, I’ve seen some brand new guys that were exceptional pilots with near zero turbine time, and some really high time guys I wouldn’t let anyone I know get in an airplane with at any price. The wrong mental attitude has killed more people than any other cause in flying, and there’s no fix for that. Some very poor pilots go through long careers on luck and nothing serious going wrong. They build up the time, but are still very weak at the core should a situation arise.

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4 hours ago, Rbass said:

...We almost always have the speed brakes out descending for an approach..

A question regarding speed brakes/spoilers, especially for those who use them in real aeroplanes. I thought that you get buffet/vibration and extra noise when you deploy them which "should" I say "should", give the game away in addition to any visual indocators in the cockpit. I remember a couple of times as pax on an airliner, one of the pilots warning us about the vibration and noise and what it was. In addition when I deployed them myself in a glider - the airframe was telling me I'd altered the aerodynamics. I was of course still holding on to the lever, but still I think you know what i mean. 😉


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3 hours ago, Rbass said:

One thing you learn very fast is that hours logged is not a good indicator of skill or attitude. One thousand hours or one hour a thousand times over. 

Yup. The problem with saying that an airliner crew member has 'a lot of hours', is that it is an extremely misleading statistic. Of course it does certainly mean you've been in aeroplanes a lot if you have accrued a lot of hours, so you're probably great on the radio and know the avionics pretty well, but it also tells a potentially misleading story too; a lot of those hours, in airliner flying, are spent monitoring things whilst everything to do with actually keeping the thing in the air is automated, rather than actually with someone piloting the aircraft manually. This is a skill too of course and it should not be maligned, but when things hit the fan and you have to grab the controls, it's skills with the stick and rudder and good decision making which are what matters.

Let's say you were a hypothetical pilot on the route which PIA Flight 8303 was on (Lahore to Karachi), and on your week's shift, you flew that route back and forth for a total of ten times: This means you'd probably split the handling duties in half with your fellow crew member, so to keep things simple and ignore split sector sharing, that's five flights where you are 'the driver' for the take off and landing, plus a straight line distance of 637 miles, which means probably nearer 700 miles distance flown if we're including SIDs, STARs, holds etc etc. Most of this distance will be flown on autopilot, for about one and a half hours of actual flight time. So of that block time, you might have as little as three minutes of actual airborne stick and rudder time before you're flipping on that CMD button and letting the autopilot and FMC do the work, yet you have logged 1.5 hours of experience. This is not an unreasonable estimate for an A320: You fly the take off, climb to perhaps 600 feet and then engage the autopilot, for perhaps two minutes of actual stick time; then later you are P1 for the approach, letting the autopilot do the bulk of lining up the ILS approach, whereupon you disengage the autopilot at perhaps 200 feet to land the thing manually and retard the throttles, which is maybe a minute where you are again actually driving the thing whilst it is airborne.

Now I'm aware that sometimes approaches are flown manually and sometimes SIDs are too, but the above scenario is not an outrageously impossible one, so, let's work out what that would amount to in terms of the ratio of total hours, to actual stick and rudder experience...

On that aforementioned route, you have 90 minutes of time in the air which you log as either the P1 or the P2, of which, 2.7 percent of that time is in the driving seat whilst the aeroplane is airborne, with you at the controls and the autopilot off, but since duties are shared/split for ten flights you actually did this on only half of those flights, being the pilot monitoring for the other five flights. This means that for hours logged as either P1 or P2, we can half that 2.7 percent of stick and rudder time to  as little a 1.35 percent of the actual hours noted in your logbook. Now, if we take your total hours - and let's go big shall we and say you have 10,000 hours - which is always a figure which impresses, how many hours of this figure involves actually piloting the aeroplane with your hands on the controls? That is to say, actually driving the thing. Surprisingly little it turns out...

If we go with the above scenario, a 10,000 hour Airbus pilot could have about 135 hours of actual stick time on that A320. Now if that pilot then does not fly recreationally at all, so accrues no additional flying time, it is entirely conceivable that a 10,000 hours airliner pilot might not actually be that great a pilot at all, at least in terms of stick time. Granted, they will undeniably be a great operator if they've done all those flights without any mishaps, but it nevertheless may well be that quite a few recreational GA pilots with 500 or so hours might have way more genuine stick time than that professional pilot. 

Now of course I know it is unlikely someone will spend 10,000 hours purely on the same A320 for an uninterrupted career stint, so the above scenario is only intended to illustrate matters rather than be a genuinely actual fact example, but it does nevertheless point up a potential problem when it comes to having to do some genuine stick and rudder stuff, especially with no engines, and tells us that it should not necessarily be a mystery why a '10,000 hour pilot' might not be the hotshot that such a moniker might suggest he or she should be.

With regard to piloting experience and how this comes into play in emergencies, the utility of genuine stick time and how this matters when the rubber bands stop, we can recall two of the most famous incidents where aeroplanes have been safely landed when they had twin engine losses: US Airways Flight 1549 (aka the Miracle on the Hudson) and Air Canada flight 143 (aka the Gimli Glider).

In both cases, the crews who pulled off these landings, Chesley Sullenberger on board 1549, and Robert Pearson on board 143, were both keen pilots, also having been so in the military, and in both cases whom - also noteworthy - had considerable experience flying gliders amongst other GA light aeroplanes. Not forgetting their co-pilots on these two occasions - Jeffrey Skiles aboard 1549 and Maurice Quintal aboard 143 - whose contributions to these successful emergency landings thanks to their skills and abilities too, plus good CRM and good cooperation, should not be underestimated.

Now if there's one thing I know from flying gliders, it is that you very quickly learn to appreciate the flight characteristics of your aeroplane and how to get it down where you want it, since the option to push the thrust levers forward and go around, is not one which is available. I'm not suggesting every airliner pilot should be sent on a gliding course, but I'm inclined to think it certainly wouldn't do any harm based on what I know flying aeroplanes with no engines has done for my own piloting skills, and in looking at how Sullenberger and Pearson fared, it does at least give us something to think about. Lots of people heap praise on those two pilots for having pulled off those landings, and I do too, but in all honesty, even before I knew the outcome of those incidents, if you'd have asked me if I thought a decent pilot with glider experience as well, could pull it off, my answer would have been yes.

Edited by Chock
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