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Old 26th May 2020, 19:56   #61
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Re: Pakistan International Airlines Airbus A320 crashes near Karachi; 97 dead

Weather was fine and not sure if any other issues were there. They didn't recognize the altitude properly or were running only based on visual clues. The landing gear came out later after they damaged the engine. Hopefully pilots weren't disoriented after the covid break
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Old 26th May 2020, 20:13   #62
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Re: Pakistan International Airlines Airbus A320 crashes near Karachi; 97 dead

Not necessarily an official source, but as always a very well informed and respected source:

From the Aviation Herald

Quote:
On May 24th 2020 Pakistan's media quote a CAA official speaking on condition of anonymity that the aircraft made two attempts to land. During the first approach it appears the landing gear was still retracted when the aircraft neared the runway, the pilot had not indicated any anomaly or emergency, emergency services thus did not respond and did not foam the runway as would be done in case of a gear malfunction. The marks on the runway between 4500 feet and 7000 feet down the runway suggest the engines made contact with the runway surface, it is possible that the engines were damaged during that contact with the runway surface leading even to possibly fire.

On May 24th 2020 a spokesman of the airline said, the landing gear had not been (partially or fully) lowered prior to the first touch down. The crew did not call out the standard operating procedures for an anomaly and no emergency was declared. Most likely the crew was not mentally prepared for a belly landing and went around when they realized the engines were scraping the runway.
http://avherald.com/h?article=4d7a6e9a&opt=513

Tip: The Aviation Herald is probably one of the best sources to read about these accidents. As more information comes in, they add (highlighted in yellow) it to the main story. So you see the story developing day by day.

They will continue doing so, till the final report is published! On most aviation forums you need to dig through endless amount of posts to try and picture what is really happening.

The Aviation Herald will always verify data as much as the can before they publish. All news agencies keep a close eye on the AH. It has a well deserved, solid reputation for reporting very factually, in detail.

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Old 26th May 2020, 21:35   #63
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Re: Pakistan International Airlines Airbus A320 crashes near Karachi; 97 dead

Quote:
Originally Posted by Jeroen View Post
The unfortunate fact is that pilots have ignored warning signals before. Not necessarily on purpose, but because they were concentrating to hard at the task at hand. (e.g. landing), which leads to tunnel vision, task saturation etc. The human brain can only process so many different inputs.
...
Task saturation is a well known problem for pilots. You might read that the pilot got behind the curve. What does means that the pilot is so busy doing whatever he is doing he/she fails to take notice of other aspects of the aircraft/crew/flying that also need attention.
Now that you explain it, I can kind of understand how task saturation may completely make a pilot miss out on some warnings. In which case, shouldn't something as critical as an undeployed L/G be accompanied by artificially generated speech warnings, as it happens for "Bank angle" etc, as opposed to just a "ding ding ding".

I can understand that resulting in a cacophony of speech warnings if multiple warnings go off. But atleast in cases like this where presumably only one warning was triggered, the aviation electronics should perhaps be improved to give speech warnings.
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Old 26th May 2020, 21:50   #64
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Re: Pakistan International Airlines Airbus A320 crashes near Karachi; 97 dead

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Originally Posted by vharihar View Post
Now that you explain it, I can kind of understand how task saturation may completely make a pilot miss out on some warnings. In which case, shouldn't something as critical as an undeployed L/G be accompanied by artificially generated speech warnings, as it happens for "Bank angle" etc, as opposed to just a "ding ding ding".

I can understand that resulting in a cacophony of speech warnings if multiple warnings go off. But atleast in cases like this where presumably only one warning was triggered, the aviation electronics should perhaps be improved to give speech warnings.
I am not that familiar with Airbus specific warnings, but I imagine they were getting several very loud alarms (not just a ding ding) and most likely also a speech warning from the Ground proximity warning system which would be shouting at them PULL UP PULL UP. Maybe Airbus specialist could chime in what alarms and speech warnings would have been going off under these circumstances.

Have a look at this simple Airbus 320 CBT.



So these guys were likely already hearing and seeing multiple alarms, bells, red lights, voices etc.

Anorak fact: The USAF did some research into the effectiveness of voice commands/warnings. It found that (male) pilots responded better to female voices! I am not aware of female voices being installed on commercial jets though!

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Old 26th May 2020, 22:06   #65
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Re: Pakistan International Airlines Airbus A320 crashes near Karachi; 97 dead

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Originally Posted by V.Narayan View Post
At first sight this seems to be a case where either these two pilots will be hailed as heroes or complete incompetent morons.
After going through what is available in the public domain my mind is rapidly closing to a conclusion as to which of the two options applies here. To respect the dead I'll wait for the tapes. There is the whole cultural factor at play too - machismo, Capt is God, CRM. We've seen it play out in earlier recent memory cases of PIA. I am happy for the families of the two passengers who survived.
Quote:
Originally Posted by vharihar View Post
I can understand that resulting in a cacophony of speech warnings if multiple warnings go off. But at least in cases like this where presumably only one warning was triggered, the aviation electronics should perhaps be improved to give speech warnings.
The warnings are quite clear. Beyond a point you cannot cure for stupid.

Last edited by V.Narayan : 26th May 2020 at 22:10.
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Old 27th May 2020, 06:58   #66
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Re: Pakistan International Airlines Airbus A320 crashes near Karachi; 97 dead

Perhaps there is also a question of Safety protocol (which may not be prevalent around the world). When a plane is coming in high and hot, and abnormally so, even if the pilot indicates "I am comfortable", the Approach and ATC should be alert (even suspicious), monitor the approach and also visually confirm the condition of the plane on the finals, at which point they could alert if the landing gear is down or not. They can also keep ground crews ready with firefighting trucks positioned etc. Whether the pilot eventually pays heed to ATC warnings is a different issue, but it establishes sufficient data for a potential adverse aftermath.

What if in this case the plane had scraped the runway so badly that it couldn't lift off again? Then it would have been all over the runway. At which time, the emergency crew would not have reached on time, inspite of having sufficient indications of a certain disaster.

Last edited by fhdowntheline : 27th May 2020 at 07:01.
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Old 27th May 2020, 08:22   #67
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Re: Pakistan International Airlines Airbus A320 crashes near Karachi; 97 dead

Quote:
Originally Posted by Jeroen View Post
Not necessarily an official source, but as always a very well informed and respected source
Can a plane take off from ground in such a scenario where it made a (full/partial) belly landing? It must have resulted in a tail strike as well since it didn't get a clear take off given the lack of height?
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Old 27th May 2020, 08:40   #68
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Re: Pakistan International Airlines Airbus A320 crashes near Karachi; 97 dead

Quote:
Originally Posted by libranof1987 View Post
Can a plane take off from ground in such a scenario where it made a (full/partial) belly landing? It must have resulted in a tail strike as well since it didn't get a clear take off given the lack of height?
If the theory that the pilots were high and hot is true, then the aircraft would have touched the runway at a pretty good speed which would allow it to lift off without too much of a pitch up. Another thing to consider is that the scrape mark begins quite towards the middle of the runway which supports this theory that the aircraft came in too fast, and hence would have had enough lift to get back into the air without too much of a pitch up when the pilots did the go around.

There are reports that the cockpit voice recorder was only partially recovered and the main data module isnt found. Isnt the CVR built such that it doesnt get damaged during crashes?

Last edited by audioholic : 27th May 2020 at 08:42.
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Old 27th May 2020, 09:36   #69
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Re: Pakistan International Airlines Airbus A320 crashes near Karachi; 97 dead



The issue of coming in for landing too fast described here.

But the issue of two attempts to land. It scraped the runway once and for the second approach, it crashed in the residential area.

This is my understanding from the data available in the public domain so far.

Last edited by norhog : 27th May 2020 at 09:38.
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Old 27th May 2020, 12:07   #70
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Re: Pakistan International Airlines Airbus A320 crashes near Karachi; 97 dead

Quote:
Originally Posted by libranof1987 View Post
Can a plane take off from ground in such a scenario where it made a (full/partial) belly landing? It must have resulted in a tail strike as well since it didn't get a clear take off given the lack of height?
yes, it can. See the video I shared earlier showing a twin prop plane doing exactly this. I am not aware that we have ever seen a commercial jet liner do this before. But from all what is known currently, this is what has happened.

Personally, I think at the very last minute they did notice the Landing Gear was not deployed and initiated a go around. But at that point they were too low and the plane did strike the runway. It looks as if the engine pods hit the runway rather than the fuselage. Which when you look at an Airbus 320 cross section makes sense. Maybe they also had a tail strike when they tried to lift off again.

The current theory is the engine pods hit the runway. A lot of equipment and gears are at the bottom of the engine, so they would have been damaged badly from hitting the ground.

The so called RAT (Ram Air Turbine) deployed as can be seen on several photographs after the first landing attempt. Which indicates a dual engine failure. When both engines fail the RAT will automatically deploy and powers some flight control system so the pilots can maintain control. But this close to the ground with all power lost gliding will only get you so far. Not far enough in this, very sad, case.

Quote:
Originally Posted by norhog View Post
The issue of coming in for landing too fast described here.
He describes it well and clearly. He uses the same graphs, with some additional information, I have posted before.

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Old 27th May 2020, 13:54   #71
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Re: Pakistan International Airlines Airbus A320 crashes near Karachi; 97 dead

Quote:
Originally Posted by Jeroen View Post
But this close to the ground with all power lost gliding will only get you so far. Not far enough in this, very sad, case.
In-spite of losing both the engines, they attained a good altitude (is it some 3500 ft?) in that TOGA which was good enough (I assume) to glide during the second attempt. Isn't it that they screwed it up again even the second attempt?

Correct me if I am wrong.

Quote:
Originally Posted by audioholic View Post
There are reports that the cockpit voice recorder was only partially recovered and the main data module isnt found. Isnt the CVR built such that it doesnt get damaged during crashes?
Picture of FDR by the way:

Pakistan International Airlines Airbus A320 crashes near Karachi; 97 dead-emay26e.jpg

And a representation of the fatal flight:

Last edited by balenoed_ : 27th May 2020 at 14:06.
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Old 27th May 2020, 14:02   #72
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Re: Pakistan International Airlines Airbus A320 crashes near Karachi; 97 dead

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Originally Posted by balenoed_ View Post
In-spite of losing both the engines, they attained a good altitude (is it some 3500 ft?) in that TOGA which was good enough (I assume) to glide during the second attempt. Isn't it that they screwed it up again even the second attempt?
The fact that they did manage to get back up (I think they struggled to get to 2000ft) suggests that the engines initially after impact still were producing sufficient thrust. But pretty quickly once at that altitude they must have failed. The RAT deployed and from that moment onwards they were just a glider.

We don’t have any real insights in to how they handled that situation from there onwards. I am unfamiliar with the Airbus engine out characteristics to make any calls whether they should have been able to return and glide to safe landing. With a big airliner, lots of alarms, no thrust, many systems lost/impaired, limited manoeuvrability, low altitude you run out of options very very quickly. They came down about 1300 m short of the runway threshold I believe. As they say, close but no cigar.

Jeroen

Last edited by Jeroen : 27th May 2020 at 14:31.
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Old 27th May 2020, 14:09   #73
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Re: Pakistan International Airlines Airbus A320 crashes near Karachi; 97 dead

I'm really hoping for the departed pilots' legacy's sake that some technical malfunction caused the landing gear not to deploy & the heavy physical jerk of 1st landing unlatched them and resulted in landing gear deployment albeit much later than needed.

But then again, realistically - their scary approach angle on the short final and place where they impacted the runway currently seem to point to pilot error. I am inclined to even consider a miracle the fact that the plane did not structurally disintegrate on that impact & managed to still get back in the air with minimal damage. They must have carried above normal airspeed considering their steep approach angle. Add the significant amount of fuel weight (looking at the fireball, there was quite a bit onboard).

Last edited by Reinhard : 27th May 2020 at 14:12.
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Old 27th May 2020, 14:13   #74
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Re: Pakistan International Airlines Airbus A320 crashes near Karachi; 97 dead

Quote:
Originally Posted by balenoed_ View Post
In-spite of losing both the engines, they attained a good altitude (is it some 3500 ft?) in that TOGA which was good enough (I assume) to glide during the second attempt. Isn't it that they screwed it up again even the second attempt?

Correct me if I am wrong.
3500 feet {or was it 2000 feet} is way too low for such a large aircraft to glide from more so when it is pointing in the wrong direction to the landing approach and is already only flying at {my guess} ~150 knots. He still had to make a turn {huge energy loss there} glide down to pick up speed, align the aircraft with the runway and then make his gliding down landing. A typical thumb rule is a 10:1 -- for every 10 kms the aircraft glides {with both engines non-functional} it loses 1000 metres of altitude. So if an aircraft loses both engines at say 10,000 meters (i.e. 33,000 feet) the pilot has about 100 kms of gliding room to find a field to land in assuming that at 33,000 feet the machine was cruising at its usual cruise speed of say 480 knots. But with both engines burning out seconds after the second take off and with the machine at a low speed they were already dead. Given that all this from first touch down to crash happened in a very short time and the pilots must have been coping with unimaginable overload I wouldn't use the phrase "screwed it up again". We might not have done any better.

Hurtling down from approx 10,000 feet at 7000 feet a minute to catch the glide slope!!! - just to share a context here --The Hawker Hunter transonic jet fighter, an icon of the 1950s, had a climb rate of 8000 feet a minute! A typical airliner at take off goes up at 2000 to at the very most 2500 feet a minute. The pilots , in my restricted presumption made their fundamental errors in the first landing attempt itself and may have been so preoccupied they simply forgot about the landing gear!

Last edited by V.Narayan : 27th May 2020 at 14:28.
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Old 27th May 2020, 14:28   #75
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Re: Pakistan International Airlines Airbus A320 crashes near Karachi; 97 dead

With reference to the video posted by Balenoed about the flight representation, the Captain at 3:15 (apparently out of curiosity), just moments after take off, asks Lahore ATC about the runway lights.

Shouldn't he be preoccupied with flying or monitoring the departure procedure, flap retraction etc. Even if it is a mere observation, a pilot would hold it off until they have cleared the airport control area. It's not like something that posed immediate danger to the plane.
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