PIA A320 Crash Karachi
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High speed and high altitude aircraft possess an abundance of both Kinetic and Potential energy. As profile drag increases as the square of IAS, then increasing drag (Speedbrakes, etc) at high speed will destroy more energy than it will at lower speeds. Slowing the aircraft down and then using speed brakes will not have as much effect as using the speed brakes at high speed before reducing.
Yes, drag increases with the square of IAS, but so does lift. And lift always (+/- a few percent) has to equal weigt, hence you can not vary drag by selecting speed that easily.
However, speed brakes produde the same delta in CD at any speed, but the lower the CL the higher the impact on L/D, and with L being constant this is what finally gives you drag. So at high speed with low CL, the effect of a delta CD is higher than at high CL, which in the end means the same: at high speed and low CL speed brakes are most powerful.
You may however not be allowed to fully deploy them at high speed (or hydraulics may not be able to fully deploy them against the high loads)
Can somebody do the quick math how steep an A320 can dive at the maximum speed at which full spoilers are allowed? More or less than the -15° nose down flight path the envelope protection does allow?
(15° nose down however feels like 45° the first time a non-aerobatic pilot tries it...)
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The A320 is capable of a surprisingly rapid rate of descent if called for. One day, when I was a new F/O on type and new to jets, we received an ATC clearance which required a higher than normal rate of descent from a mid flight level. I knew this was achieved by disconnecting the autopilot, so that full speed brakes could be applied, and selecting a speed just below the barbers pole. This caused the VSI to proceed well into the amber and gave a very good view of the whites of the Captain's eyes. We easily met our ATC requirement. 
Even without SB the 319 gets some pretty interesting angles and rates of descent when empty and cleared to descend when ready, best speed, cancel 250 below 10 to final. Surprised more than one ATC.
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Can somebody do the quick math how steep an A320 can dive at the maximum speed at which full spoilers are allowed? More or less than the -15° nose down flight path the envelope protection does allow?
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Last edited by jimtx; 2nd Jun 2020 at 21:27.
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FDR & CVR successfully downloaded by BEA/Pakistan AAIB. Data analysis in progress now:
https://twitter.com/i/web/status/1267868945337499648
https://twitter.com/i/web/status/1267868945337499648
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I've seen a Pakistani pilot mention this on one of his otherwise excellent YouTube analysis videos. I'm afraid it's rubbish. This was a clear day, with good visibility and they would've seen the unusual and crazy angle at which they were approaching the runway from more than 10 miles away. No evidence for it.
For me the best instrument is the mark 1 eye ball. The first consideration in airmanship is look out. I think most of us would agree.
Anything is possible, where humans involved.
Last edited by Dan_Brown; 2nd Jun 2020 at 19:59.
OK I have a question (not a postulation of what did happen)
I noted among all the pictures (this event or otherwise) that landing on the engines tends to at least partially deploy the engine reverser sleeves.
Assuming the sliding forces are large enough t oat least result in an "unlocked state) would this send a signal to the engine FADEC to retard the engine presuming that the gear was not down?
This of course may be in-service model specific
I noted among all the pictures (this event or otherwise) that landing on the engines tends to at least partially deploy the engine reverser sleeves.
Assuming the sliding forces are large enough t oat least result in an "unlocked state) would this send a signal to the engine FADEC to retard the engine presuming that the gear was not down?
This of course may be in-service model specific
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Here's an article by ARY News. It reads like it was written by the summer intern with Google Translate.
So far, as suspected. Over the threshold at 210 knots, high on the glide, refused a turn or vectors to get on profile. Even if they put the wheels down on the first try the outcome might have been similar.
The warnings cancelled, they missed lunch, they were tired, they hadn't flown lately and forgot to be stable at 1000 feet, KHI is their home base and they were over confident, society failed them etc. I predict that the litany of excuses will become ever more convoluted as the search for answers continues.
KARACHI: The Civil Aviation Authority (CAA) has released a report regarding ‘violations’ made by pilot of ill-fated PK-8303 aircraft of Pakistan International Airlines (PIA) which was crashed on May 22, ARY News reported on Tuesday.
The Civil Aviation Authority’s Additional Director Operation sent a letter to the safety department of the national flag-carrier, Pakistan International Airlines (PIA). The copy of the letter was obtained by ARY News which stated that the pilot of the Airbus 320 aircraft did not follow the instruction of the air traffic controller (ATC).
It stated that the altitude of the plane was high at the approach point and the air traffic controller had warned the captain of PK-8303 regarding it. The altitude of the plane was 5,200 feet at the seven nautical miles that is considered high from the approach profile.
The ATC had warned the captain twice and instructed to turn the plane to 180 degrees besides maintaining the required altitude, however, the instructions were completely neglected by the pilot, said the report.
It also stated that the plane fell down to 1,300 feet altitude from 3,500 feet at the four nautical miles, whereas, the speed of the aircraft was more than 250 knots before landing which is also considered high from the required acceleration.
The report was followed by the written response of air traffic controller (ATC) and approach tower controllers which had been submitted to the investigation board on May 26 during the probe of Pakistan International Airlines (PIA) plane, PK-8303, crash incident.
It stated that the approach tower controller had handled the flight from Lahore to Karachi and the task was handed over to the ATC to make the plane safely landed at the airport. The landing task had been given by the approach tower to the ATC after 10 nautical miles.
Later, the captain had asked permission to land once again and informed the control tower that both engines of the aircraft were not working. The plane had been granted permission to land at the left side of runway number 25. According to the ATC and approach tower controller, the captain of the aircraft had been informed them regarding any kind of emergency. The captain had told the air traffic controller that he was calm and he will manage to land the aircraft.
However, the aircraft with more than 90 passengers and eight crew members on board had crashed in a residential area, Model Colony, moments before expected landing at the Karachi’s Jinnah International Airport. Only two passengers had survived the deadly accident.
https://arynews.tv/en/pia-plane-cras...ort-pilot-atc/
So far, as suspected. Over the threshold at 210 knots, high on the glide, refused a turn or vectors to get on profile. Even if they put the wheels down on the first try the outcome might have been similar.
The warnings cancelled, they missed lunch, they were tired, they hadn't flown lately and forgot to be stable at 1000 feet, KHI is their home base and they were over confident, society failed them etc. I predict that the litany of excuses will become ever more convoluted as the search for answers continues.
PK-8303 crash: Pilot violated instructions of ATC, says CAA report
Salah Uddin On Jun 2, 2020KARACHI: The Civil Aviation Authority (CAA) has released a report regarding ‘violations’ made by pilot of ill-fated PK-8303 aircraft of Pakistan International Airlines (PIA) which was crashed on May 22, ARY News reported on Tuesday.
The Civil Aviation Authority’s Additional Director Operation sent a letter to the safety department of the national flag-carrier, Pakistan International Airlines (PIA). The copy of the letter was obtained by ARY News which stated that the pilot of the Airbus 320 aircraft did not follow the instruction of the air traffic controller (ATC).
It stated that the altitude of the plane was high at the approach point and the air traffic controller had warned the captain of PK-8303 regarding it. The altitude of the plane was 5,200 feet at the seven nautical miles that is considered high from the approach profile.
The ATC had warned the captain twice and instructed to turn the plane to 180 degrees besides maintaining the required altitude, however, the instructions were completely neglected by the pilot, said the report.
It also stated that the plane fell down to 1,300 feet altitude from 3,500 feet at the four nautical miles, whereas, the speed of the aircraft was more than 250 knots before landing which is also considered high from the required acceleration.
The report was followed by the written response of air traffic controller (ATC) and approach tower controllers which had been submitted to the investigation board on May 26 during the probe of Pakistan International Airlines (PIA) plane, PK-8303, crash incident.
It stated that the approach tower controller had handled the flight from Lahore to Karachi and the task was handed over to the ATC to make the plane safely landed at the airport. The landing task had been given by the approach tower to the ATC after 10 nautical miles.
Later, the captain had asked permission to land once again and informed the control tower that both engines of the aircraft were not working. The plane had been granted permission to land at the left side of runway number 25. According to the ATC and approach tower controller, the captain of the aircraft had been informed them regarding any kind of emergency. The captain had told the air traffic controller that he was calm and he will manage to land the aircraft.
However, the aircraft with more than 90 passengers and eight crew members on board had crashed in a residential area, Model Colony, moments before expected landing at the Karachi’s Jinnah International Airport. Only two passengers had survived the deadly accident.
https://arynews.tv/en/pia-plane-cras...ort-pilot-atc/
OK I have a question (not a postulation of what did happen)
I noted among all the pictures (this event or otherwise) that landing on the engines tends to at least partially deploy the engine reverser sleeves.
Assuming the sliding forces are large enough t oat least result in an "unlocked state) would this send a signal to the engine FADEC to retard the engine presuming that the gear was not down?
This of course may be in-service model specific
I noted among all the pictures (this event or otherwise) that landing on the engines tends to at least partially deploy the engine reverser sleeves.
Assuming the sliding forces are large enough t oat least result in an "unlocked state) would this send a signal to the engine FADEC to retard the engine presuming that the gear was not down?
This of course may be in-service model specific
Now, on Boeing, it takes more than 'unlocked' for a thrust cutback - the thrust cutback is based on the FADEC sensed actual reverser position (there is some special logic that comes into play if the sensed position is different between the channels). Typically nothing happens until the reverser is more than 10% from the commanded position. For example, if closed is 0%, thrust cutback will start at 10% and limited to idle at 15% - same thing at the other end between 85% and 90% deployed.
Now, as noted, that's how the Boeing installation works, but I'd be a bit surprised if Airbus is much different.
kit: No interim report so far, so one would not expect that detail to be released until then.
Whether or not it has been leaked someone else might know.
Whether or not it has been leaked someone else might know.
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Here's a report from ARY News:
On another forum it was claimed that Captain Gul was the senior pilot at PIA. However, often with translations, transliterations, typos and second hand information these primacy claims are often misstated in my observation.
The phrase 'Gul was senior pilot at PIA' might be 'corrected' different ways for example.
The first officer was Usman Azam. I remember reading somewhere, maybe here, that he had thousands of hours but not a lot of time on the A320. Whether this was true or speculation anybody know?
The Aircraft Accident and Investigation Team while investigating various aspects of the air crash, has demanded overall flying record of Captain Sajjad Gul from the Chief Pilot Safety of the Pakistan International Airlines (PIA).
The probe team has inquired about the flying routes of the pilot and also asked about the details of the log book and whether the Captain was observing fast during the flight.
The inquiry team has also asked questions about a Lahore to Karachi flight two days ago, inquiring whether the same pilot had operated a flight on the route two days ago on May 20, sources said. The issue of purported flying fatigue of the pilot also being inquired about, according to sources.
Earlier, Captain Sajjad Gul’s father in a media briefing said that his son had logged in 17,000 hours. He was the only pilot to have completed 1,000 hours in a year and a thorough professional, said the aggrieved father.
The probe team has inquired about the flying routes of the pilot and also asked about the details of the log book and whether the Captain was observing fast during the flight.
The inquiry team has also asked questions about a Lahore to Karachi flight two days ago, inquiring whether the same pilot had operated a flight on the route two days ago on May 20, sources said. The issue of purported flying fatigue of the pilot also being inquired about, according to sources.
Earlier, Captain Sajjad Gul’s father in a media briefing said that his son had logged in 17,000 hours. He was the only pilot to have completed 1,000 hours in a year and a thorough professional, said the aggrieved father.
The phrase 'Gul was senior pilot at PIA' might be 'corrected' different ways for example.
The first officer was Usman Azam. I remember reading somewhere, maybe here, that he had thousands of hours but not a lot of time on the A320. Whether this was true or speculation anybody know?
Loma, first off I'd be surprised if the reverser moved much - there are locking actuators that shouldn't unlock in the absence of hydraulic pressure. The stowed prox sensors may go 'target far', but the actual reverser movement would be small.
Now, on Boeing, it takes more than 'unlocked' for a thrust cutback - the thrust cutback is based on the FADEC sensed actual reverser position (there is some special logic that comes into play if the sensed position is different between the channels). Typically nothing happens until the reverser is more than 10% from the commanded position. For example, if closed is 0%, thrust cutback will start at 10% and limited to idle at 15% - same thing at the other end between 85% and 90% deployed.
Now, as noted, that's how the Boeing installation works, but I'd be a bit surprised if Airbus is much different.
Now, on Boeing, it takes more than 'unlocked' for a thrust cutback - the thrust cutback is based on the FADEC sensed actual reverser position (there is some special logic that comes into play if the sensed position is different between the channels). Typically nothing happens until the reverser is more than 10% from the commanded position. For example, if closed is 0%, thrust cutback will start at 10% and limited to idle at 15% - same thing at the other end between 85% and 90% deployed.
Now, as noted, that's how the Boeing installation works, but I'd be a bit surprised if Airbus is much different.