PIA A320 Crash Karachi
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You might want to have a closer look at the picture in post #85
https://www.pprune.org/rumours-news/632693-pia-a320-crash-karachi.html#post10790064
If you look at the nacelles it is clear this wasn't just an oil leak. They are torn on the bottom. Those pods 100% scratched the tarmac. At a nose high attitude.
https://www.pprune.org/rumours-news/632693-pia-a320-crash-karachi.html#post10790064
If you look at the nacelles it is clear this wasn't just an oil leak. They are torn on the bottom. Those pods 100% scratched the tarmac. At a nose high attitude.
AVH now reporting that sources within Pakistani CAA confirm ground contact was made with retracted gear on first approach, there was no communication of any fault or gear issue prior to the go-around. Sadly this confirms all that was suspected following the release of the PSPK photos.
From the wording it is not yet clear if the gear remained retracted throughout the approach, or if it was retracted before a positive climb was achieved, however the MLG doors would have been damaged if the gears were in transit while making the ground contact (Smartlynx), but no such damage is visible on the photos.
From the wording it is not yet clear if the gear remained retracted throughout the approach, or if it was retracted before a positive climb was achieved, however the MLG doors would have been damaged if the gears were in transit while making the ground contact (Smartlynx), but no such damage is visible on the photos.
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Looks like unstable high energy approach & basically Messed it up by the time they realized TOGA and damage was done to the Port & Starboard side engine” scrapes , possibility is oil lines leak & flame out/ compressor stall by the time they were downwind”
My 2 cents worth people,
Looking at those marks on the engines, there is no way those marks are due to contact with the runway/ground. If there was contact, there would be some rather large obvious flat spots under those engines. The angle of those marks at the trailing edge of both engine cold stream ducts would indicate that not only half of the engine exhaust cones should be missing/ground away, BUT half of the rear fuselage as well !!! IMHO.
Lets leave it to the expert investigators.
Looking at those marks on the engines, there is no way those marks are due to contact with the runway/ground. If there was contact, there would be some rather large obvious flat spots under those engines. The angle of those marks at the trailing edge of both engine cold stream ducts would indicate that not only half of the engine exhaust cones should be missing/ground away, BUT half of the rear fuselage as well !!! IMHO.
Lets leave it to the expert investigators.
Also possible that the gear was retracted before the flaps during the go-around. Standard procedure is “Go Around - FLAPS, retract one stage, positive climb - GEAR UP.
Perhaps it happened out of sequence by mistake, “Go Around” and the wheels went up first instead of the flaps.
Perhaps it happened out of sequence by mistake, “Go Around” and the wheels went up first instead of the flaps.
henra,
"They (engine cowls) are torn on the bottom."
Looking at a slightly magnified view of that photo, all edge surfaces appear 'torn' (top/bottom fuselage, fin) due to photo resolution / enlargement.
As per Capt McHale, extrapolating the cowl marks rearward, suggest that there should also be rear fuselage / tail damage.
whereas oil stains … follow the airflow …
"They (engine cowls) are torn on the bottom."
Looking at a slightly magnified view of that photo, all edge surfaces appear 'torn' (top/bottom fuselage, fin) due to photo resolution / enlargement.
As per Capt McHale, extrapolating the cowl marks rearward, suggest that there should also be rear fuselage / tail damage.
whereas oil stains … follow the airflow …
Too much assigning of fact to all the speculations so far.
I don't accept all the supporting arguments as real fact.
For example surely those on site know where the engine cowls are damaged sufficiently to disable the engine (runway scrapes, cowl fire damage or wear through). Cowl crushing sufficient to damage systems?
And what about past history of similar installations? Don't investigative reports have cowl runway impacts in them of similar severity?
I don't accept all the supporting arguments as real fact.
For example surely those on site know where the engine cowls are damaged sufficiently to disable the engine (runway scrapes, cowl fire damage or wear through). Cowl crushing sufficient to damage systems?
And what about past history of similar installations? Don't investigative reports have cowl runway impacts in them of similar severity?
Not possible IMHO due to landing gear interlock
If there was contact, there would be some rather large obvious flat spots under those engines.
The cowling material will probably tear away and the structure underneath will remain circular. I don't think what we see in those pictures contradicts a contact with the runway. Anyway the final report will tell us the truth.
The angle of those marks at the trailing edge of both engine cold stream ducts would indicate that not only half of the engine exhaust cones should be missing/ground away, BUT half of the rear fuselage as well !!! IMHO.
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The one thing I am really struggling with is whether they were 3500 feet 5 miles from touchdown - I just cannot see how anyone would continue an approach- crew incapacitation ( they certainly lacked capacity but couldthere be a reason)
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Capt Quentin McHale
You can't just project the angle of those marks rearward. First, you cant distinguish oil/smoke marks from scrape marks, and second, if it scraped, the nacelles and struts would flex upward significantly resulting in the trailing edge areas having more damage than one might expect if they imagine the airplane as being perfectly rigid.
You can't just project the angle of those marks rearward. First, you cant distinguish oil/smoke marks from scrape marks, and second, if it scraped, the nacelles and struts would flex upward significantly resulting in the trailing edge areas having more damage than one might expect if they imagine the airplane as being perfectly rigid.
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Also possible that the gear was retracted before the flaps during the go-around. Standard procedure is “Go Around - FLAPS, retract one stage, positive climb - GEAR UP.
Perhaps it happened out of sequence by mistake, “Go Around” and the wheels went up first instead of the flaps.
Perhaps it happened out of sequence by mistake, “Go Around” and the wheels went up first instead of the flaps.
As a general technique to intercept glide slope from above, pilots would early lower the landing gear to increase drag to reduce speed when in high descent rate. So except the TOO LOW GEAR warning, over speed warning will remind pilots to lower the gears, too. It's less possible the pilots FORGET to make the gear down.
Something had put the likelyhood of a belly landing so firmly in ATC's mind that they actually included a question about it - most unconventionally - in their response to the g/a. They simply wouldn't say that without some very compelling reason. I can think of no other feasible compelling reason other than that they'd already witnessed one seconds before.
Very clearly there was severe damage to both nacelles but no sign of u/c deployed - there's only one way that can happen, ground contact with gear retracted.
The speculation on sink after go-around is called and gear prematurely retracted (perhaps mistakenly instead of flap) sounds by far the most feasible way to circumvent all the warnings - a severe impact on both pods disabling the generators and quite possibly hydraulics and even oil system (my 320 tech is largely forgotten now - perhaps the entire accessory drive system?) which could accont for the rapid loss of both engines. It would be relatively easy and quite credible to severely mishandle a g/a at the end of a high-anxiety unstable approach.
Why fly away from such an event? With TOGA or someting like it already applied, the pucker factor has PF instinctively pulling back on his stick as contact is made and they are flying again. After so much confusion in the preceeding couple of minutes it would surprise me if a crew in that situaton would have the capacity to close the thrust levers and reland, it would only take a couple of seconds of freeze, if that, and they're 15' nose up climbing fast and utterly committed to the g/a. They may not even have had room to reject from there but one suspects that level of cognition may not have been present.
But why no flap deployed in the photos though? Did they get high enough to retract them?
Psychophysiological entity
It's a strange fuzz, but this explains a lot to an oldtimer that's used to metal.
I wonder if the entire pod rotated/distorted jet pipe down just a tad as the front's impacted.
I was aware of the possibility of pod strikes before coming on this site. The BBC news had given some clue or another. For me it seems the best bet now the fuzzy surface might be explained.
and the cowls are carbon composite...
I was aware of the possibility of pod strikes before coming on this site. The BBC news had given some clue or another. For me it seems the best bet now the fuzzy surface might be explained.
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May I remind you of these words once the final report is out?
Those cowlings are only thin covers. Underneath is the massive structure designed to contain fan/turbine blades in case of separation.
The cowling material will probably tear away and the structure underneath will remain circular. I don't think what we see in those pictures contradicts a contact with the runway. Anyway the final report will tell us the truth.
the black marks on the side towards the rear of the cowlings have not necessarily contacted the tarmac itself. That could be sooting from the heat or oil stain.
Those cowlings are only thin covers. Underneath is the massive structure designed to contain fan/turbine blades in case of separation.
The cowling material will probably tear away and the structure underneath will remain circular. I don't think what we see in those pictures contradicts a contact with the runway. Anyway the final report will tell us the truth.
the black marks on the side towards the rear of the cowlings have not necessarily contacted the tarmac itself. That could be sooting from the heat or oil stain.
The structure at the bottom of the engine isn't "massive" relative to the weight and speed of the airplane. The transfer gearbox and the low end of the accessory gearbox are at or very near the bottom center line. The cowls are light weight structure not sized to support the airplane without damage. If you scrape the engines significantly you are likely to put holes in the accessory and transfer gearboxes, and will very quickly lose the engine oil. Bearing failure will then follow quickly if high power is commanded.
The regulatory requirements are for such an event are intended simply to not breach the fuel system for crash safety reasons (see 14 CFR 25.994).
Sec. 25.994
Fuel system components.
Fuel system components in an engine nacelle or in the fuselage must be protected from damage that could result in spillage of enough fuel to constitute a fire hazard as a result of a wheels-up landing on a paved runway under each of the conditions prescribed in § 25.721(b).
The requirements and design intent have never been to maintain ability to continue running the engine at high power following such a scrape event. They are simply intended to prevent post-crash fire in a wheels up controlled landing.