Another Aircraft Missing in SE Asia: QZ8501

[Mungoman]

G'day Folks, in this neck of the woods around Darwin, at this time of the year, it's called 'the wet' (monsoon or cyclone season), so those 'thunderstorms' wouldn't be the average thunderstorm that we envisage - they'd be bastards to try to fly around - I can't see this having a good ending. Unfortunately.

 

[Swifty]

I didn't realise that the area they're searching in is estimated at roughly the size of California ... that makes things less suspicious and more plausible to me if they don't find the plane or any wreckage.

 

[Andy X]

I just disturbed husband, who was busy sanding kitchen worktops, ( after I have been nagging him to do so for months ) who was only to happy to supply a detailed explanation. Please see below :

1. Icing on wing leading edge causes the wing's aerodynamics to be upset as the shape or chord changes.
This causes :
a. Stall speed increases.
b. Max speed decrease.
The above is due to an increase in drag and spoiling of air flowing over top of wing.

2. Icing on baro system such as pitot probes can occur leading to serious effects.
One is blocking of tubes which causes aircraft systems to see no pressure which is interpreted as low speed. In normal aircraft a pilot would react to this and cross check. In fly by wire systems the aircraft will try to correct by increasing speed or pitching down to increase speed (envelope protection). In normal aircraft the pilot can also do this manually.

Pitching down coupled with loss of aerodynamic performance can cause catastrophic effects. Pitot systems are dual redundant and all aircraft have some deicing capability.

And finally, 'im indoors says, "Pilots try to avoid icing like the plague".

Sensible points. Many serious accidents have resulted from pilots struggling to get their heads around confusing & contradictory indications from aircrafts' highly complex systems and so reacting far too slowly, the cause of their confusion often turning out to be something quite simple, and often physical in nature.

I only have experience in General Aviation, so am not in any way pretending to know about flying an A320, but have been talking to colleagues who do know what they're on about, being biz jet and scheduled airline pilots, some on Boeings, some Airbus, and they totally agree about icing possibly being a factor. Depending on which of the various (and duplicated for safety) pitot tubes, static ports, or angle-of-attack (the angle at which the wing presents itself to the oncoming airflow) sensors had, in this icing scenario, become partially or totally blocked by sludge, the aircraft's systems would misinterpret the data, particularly in relation to airspeed (kind of important if climbing rapidly - especially through a thunderstorm, where barometric pressure and windshear will vary, for example) and may automatically attempt any number of computerised pitch and/or power changes to rectify the situation as per software algorithms. This could, if undiagnosed by the flight crew, lead to an unrecoverable stall (especially if turbulent airflow due to ice on the wings' leading edges had already raised the actual stall speed at which the wings stop generating lift), or in the case of AoA sensor failure, initiate a nose-down descent in a mistaken attempt to maintain apparently decaying airspeed and keep the wings' Angle of Attack within the acceptable range -. Even the most alert pilots can become muddled and fail to apprehend the true nature of such situations in time to return the aircraft to a normal flight regime. And no airline pilot is likely to just disengage the automatics straight away without having figured out how to fly themselves out of trouble with manual inputs. By which time it can be too late to intervene successfully.

Also it now appears the aircraft changed course quite rapidly in a climbing turn, suggesting an angle of bank which though not recklessly excessive in the cruise, could result in worryingly reduced performance in a nose-up attitude ie. less speed, less lift, and more drag than in a straight and level turn - which would also contribute to a dangerously low aerodynamic stall speed - all whilst approacing, or entering, a thunderstorm. There's been a suggestion that sharp turns at altitude in the A320 directed by twiddling the knobs on the Flight Control Unit (autopilot, basically) are perhaps not a great idea anyway.


TL;DR: my expert friends reckon, sorry to say, that the flight probably went into the ocean due to getting into difficulties in the storm, likely exacerbated by icing at various locations. As has been pointed out, the vulnerable areas of aircraft are supplied with heating and sophisticated monitoring, and systems are improved all the time, but accidents can happen, and the more complex a machine the more there is to go wrong. And the more bewildering it can be for the human brain if it does. We'd all like to think that passengers and crew will turn up somewhere and be rescued, but assuming not, and without any compelling proof of a sinister motive by third parties, I'm afraid it just looks like an awful tragedy.

 

[Andy X]

Not if the readings are incorrect ( as they would be in above scenario ). Either the plane takes over, or the pilot doesn't double check and takes the incorrect action - both lead to catastrophic failure. By the time pilots are aware of this, they are already nose diving into the ocean ( to put it bluntly ) and at that point they will be desperately trying to aviate, rather than talk to airtraffic control.

Exactly: The golden rule is: Aviate, Navigate, Communicate.

In that order.

 

[rynner2]

AirAsia QZ8501: Debris seen by Indonesia search teams
Indonesian officials say search teams have spotted debris at sea in the hunt for missing AirAsia Flight QZ8501.
Several objects including a body were seen floating in the Java Sea off the Indonesian part of Borneo, in one of the search zones for the plane.
Indonesian officials said the debris was likely to be from the missing aircraft.
The Airbus A320-200, carrying 162 people from Surabaya in Indonesia to Singapore, disappeared on Sunday.

The debris is said to be different to other objects spotted during the search

It's still not clear what the objects are

The search operation is now in its third day, with the area widened to cover 13 zones over land and sea.
Indonesian civil aviation chief Djoko Murjatmodjo, quoted by AFP news agency, said "significant things" such as a passenger door and cargo door had been found.
"For the time being it can be confirmed that it's the AirAsia plane," he said.

Mr Murjatmodjo added that the objects had been found 160km (100 miles) south-west of Pangkalan Bun, a town in the Indonesian province of Central Kalimantan.
Meanwhile, during a news conference by the head of the search operation, pictures of the debris were shown, including a body floating on the water.
Relatives of passengers on the plane watching the pictures were visibly shocked.

Officials said all resources were now being sent to the area where the debris was found, and all objects or bodies found will be taken to Pangkalan Bun.
At least 30 ships, 15 aircraft and seven helicopters joined the operation when it resumed at 06:00 local time on Tuesday (23:00 GMT Monday).

Search and rescue operations are now in their third day

Family and friends of those on board the plane are gathered and awaiting news at Surabaya airport

The operation, led by Indonesia, includes assistance from Malaysia, Singapore and Australia, with other offers of help from South Korea, Thailand, China and France. The US destroyer USS Sampson is on its way to the zone.

Earlier, Indonesian officials said they were investigating reports of smoke seen rising from an island close to Belitung island, one of the focal points of the search, though experts cautioned it could be unrelated to the missing plane.
On board the plane were 137 adult passengers, 17 children and one infant, along with two pilots and five crew.
Most were Indonesian but the passengers included one UK national, a Malaysian, a Singaporean and three South Koreans.

The plane left Surabaya at 05:35 Jakarta time on Sunday and had been due to arrive in Singapore two hours later.
Safety officials say the captain had asked for permission to take the plane higher but, by the time permission was granted, communication with the plane was lost.
It was officially declared missing at 07:55.
AirAsia previously had an excellent safety record and there were no fatal accidents involving its aircraft.

http://www.bbc.co.uk/news/world-asia-30630330

(Couple of videos on page.)

 

[rynner2]

30 December 2014 Last updated at 09:36
AirAsia QZ8501: 'Six bodies' found in missing plane search

At least six bodies have been found and at least three recovered in the search for missing AirAsia Flight QZ8501, Indonesian officials and media say.
The bodies were spotted along with debris floating in the Java Sea off the Indonesian part of Borneo, in one of the search zones for the plane.
One official said the debris was 95% likely to be from the missing aircraft.

(same URL)

Sad for friends and relations, but good if it means the wreck can be quickly located and the black boxes recovered.

 

[skinny]

TV reports down here say that 40 bodies have been recovered. No doubt this is the wreck. Hopes are that some may have survived.

 

[rynner2]

TV reports down here say that 40 bodies have been recovered. No doubt this is the wreck. Hopes are that some may have survived.

Yes, if the passengers didn't go down with plane, there may have been a window of opportunity to escape and survive. Fingers crossed.

 

[Swifty]

Very sad news indeed .. hopefully new albeit hard learned lessons can reduce the chance of this happening again.

 

[Quake42]

The absence of any Mayday call seems strange. As others have said it would have taken time to plunge 30,000 feet plus. The pilots were clearly aware of the storm because they requested permission to climb. It's odd that there was no attempt even to provide a position which could have alerted rescuers and at least given any survivors a fighting chance.

 

[GNC]

At least there's the chance of retrieving the black box which should clear up most of the questions.

 

[rynner2]

The absence of any Mayday call seems strange. As others have said it would have taken time to plunge 30,000 feet plus. The pilots were clearly aware of the storm because they requested permission to climb. It's odd that there was no attempt even to provide a position which could have alerted rescuers and at least given any survivors a fighting chance.

The pilots may not have realised they were plunging down, if they were getting contradictory information from their instruments, whether because of icing or electrical interference.

I strongly suspect that when all the info is in, this case will prove very similar to the Air France crash in the Atlantic.

As for the plane's position, aircraft use automatic position reporting, similar to the AIS used by ships, but how that, and the radio comms, would be affected by a massive electrical storm I don't know.

Finally, it seems the number of bodies found has been revised back down to 3.
http://www.bbc.co.uk/news/world-asia-30634081

 

[Swifty]

Wouldn't general human awareness of being up or down, gravity, ear pressure have given them a clue if they were diving in this type of situation? ... I've only ever been a passenger in a plane before but remember sucking boiled sweets to stop ear pop .. I suppose normally, the pilots being able to see where they were going through the front window would have helped but then they were in a storm .. and boiled sweets weren't their priority .. perhaps they were flying at a lower altitude?

The (so far variable) body count has gone from a fuzzy 6 to 40 and the to 3? ... hate to sound like a teenage girl but .... realllly?

 

[Mythopoeika]

The (so far variable) body count has gone from a fuzzy 6 to 40 and the to 3? ... hate to sound like a teenage girl but .... realllly?

It's crap journalism again. Wait for things to settle down.

 

[rynner2]

"The head of Indonesia's search operation, Bambang Soelistyo, says three bodies have been retrieved, not 40 as previously stated by naval officials."

So don't blame 'crap journalism' - journalists can only report what they've been told.

 

[Swifty]

So, for now, we can blame the head of Indonesia's search operation Bambang Soelistyo or we can blame naval officials? ... journalists are off the hook, I want to know what's up with the 3 dead people to 40 discrepancy and the why ...

 

[Schwadevivre]

Wouldn't general human awareness of being up or down, gravity, ear pressure have given them a clue if they were diving in this type of situation? ... I've only ever been a passenger in a plane before but remember sucking boiled sweets to stop ear pop .. I suppose normally, the pilots being able to see where they were going through the front window would have helped but then they were in a storm .. and boiled sweets weren't their priority .. perhaps they were flying at a lower altitude?

The (so far variable) body count has gone from a fuzzy 6 to 40 and the to 3? ... hate to sound like a teenage girl but .... realllly?

There's a lot of problems with controlling an aircraft in a situation where you cannot see the horizon and the more so in turbulence. Electronic instruments can be influenced by lightening and even mechanical artificial horizon indicators give false readings with transient accelerations. I have also been told that the biggest problem is that if both pilots are busy with various warnings other, more urgent situations are ignored.

There was a case where a fatal crash occurred because both pilot and copilot became distracted by a faulty indicator light and ignored a ground proximity warning.

 

[Swifty]

I'd like more control on correct reporting of the fatalities for starters ..

 

[Andy X]

Wouldn't general human awareness of being up or down, gravity, ear pressure have given them a clue if they were diving in this type of situation?

Not necessarily; it can be bizarrely difficult even to tell which way up you are when moving in three dimensions with no horizon to refer to.

 

[Swifty]

Yeah, I suppose so .. I'm glad I'm not a pilot in those conditions.

 

[rynner2]

31 December 2014 Last updated at 06:10

AirAsia QZ8501: Bad weather hampers recovery of bodies

Efforts to locate victims and wreckage of AirAsia flight QZ8501 which crashed into the Java Sea in Indonesia on Sunday are being hampered by stormy weather and strong tides.
[Tides are Neap at present - Spring tides are next week. But there may be strong currents driven by stormy winds.]

Indonesian officials have confirmed that remains and debris found in the waters off Borneo are from the plane.
The authorities say that seven bodies have now been retrieved.
...
Aircraft from several countries were set to scan the sea in the early hours of Wednesday morning. Divers were also being deployed to search for bodies and for the plane's "black box" flight recorders.
But officials said heavy rain, strong winds and waves of up to 3m (10ft) had forced them to suspend the air operation, though ships already in place were continuing the search.

The head of Indonesia's National Search and Rescue Agency, Bambang Soelistyo, said another body had been retrieved from the sea on Wednesday, bringing the total to seven. One was a woman wearing cabin crew uniform.
The bodies are on board two ships but helicopters sent to bring them back to the nearest town, Pangkalan Bun, have had to turn back because of the weather, he said.
The navy had reported on Tuesday that more than 40 bodies had been recovered, but spokesman Manahan Simorangkir later told AFP news agency the figure had been a miscommunication by his staff.

etc...

http://www.bbc.co.uk/news/world-asia-30639206

 

[rynner2]

AirAsia plane found in Java Sea: latest
One of the victims of the AirAsia crash has been found wearing a life jacket - raising the suggestion that they knew they were likely to land in the sea

etc...

06.10 Update: total of 7 bodies - 4 men, 3 women - recovered so far, says search chief. One was air hostess Khairunisa Haidar Fauzi,, who was in uniform, one was in a life jacket according to reports, and three were found still holding hands.

etc...

http://www.telegraph.co.uk/news/wor...ssing-with-162-passengers-onboard-latest.html

 

[Loquaciousness]

I am not too convinced by the holding hands scenario...... surely the force of impact would have meant this wasn't possible. It does make me sick to the stomach to hear about one of the bodies wearing a life jacket though, it implies they knew exactly what was coming .

 

[rynner2]

I am not too convinced by the holding hands scenario...... surely the force of impact would have meant this wasn't possible. It does make me sick to the stomach to hear about one of the bodies wearing a life jacket though, it implies they knew exactly what was coming .

To me, this all suggests that the plane may have floated for a while after splash-down, allowing some passengers and cabin crew to get out. Somewhere I saw a report that one of the inflatable emergency evacuation slides had been found. This also suggests that the plane was on the surface for a least a short while.

But landing a plane on the Hudson River is one thing, landing it on a rough sea is another. And after one or more doors were opened, the plane would soon ship water and sink. (A cabin door and a cargo door have been found.)

 

[Quake42]

All of which makes the absence of a Mayday call all the more baffling. If passengers had time to put on life jackets the crew were clearly well aware of the desperate nature of the situation.

 

[Rosebud]

To me, this all suggests that the plane may have floated for a while after splash-down, allowing some passengers and cabin crew to get out. Somewhere I saw a report that one of the inflatable emergency evacuation slides had been found. This also suggests that the plane was on the surface for a least a short while.

But landing a plane on the Hudson River is one thing, landing it on a rough sea is another. And after one or more doors were opened, the plane would soon ship water and sink. (A cabin door and a cargo door have been found.)

I was thinking the same.
Like Quake, I wonder why no beacons were activated on the life jackets and at least one raft which did make it into the water. Very sad to think they may have survived the crash only to perish in the sea.

As to the initial report of 40 bodies; I don't know which language they were communicating in, but the Chinese word for 'death' is very similar to the word for 'four' (si) which is why a lot of their buildings have no fourth floor. Could this have been a factor in the mix up?

 

[ramonmercado]

My sister and brother in law are flying home from Perth as my father is quite ill and they will fly over that general area. I suppose shes just being practical but she told me where their wills are.

 

[Rosebud]

My sister and brother in law are flying home from Perth as my father is quite ill and they will fly over that general area. I suppose shes just being practical but she told me where their wills are.

Awww, Ramon, sorry to hear that your father is poorly, I hope he recovers.

The one good thing about this tragedy is that any slipshod practices are likely to be tightened up, at least for the time being.

 

[ramonmercado]

Awww, Ramon, sorry to hear that your father is poorly, I hope he recovers.

The one good thing about this tragedy is that any slipshod practices are likely to be tightened up, at least for the time being.

Thanks. Hes 88 and suffered another fall last month, hes in hospital since then, got minor pneumonia, got over that and now has a clot in his lung.

 

[honeyplanet]

Daily mail article stated that reports of body wearing life jacket are now incorrect, no doubt that will change again. I also think the plane floated for a short while, simply awful way to go those poor people. I also read the plane is lying upside down on the seabed, I don't know why I allways picture planes going down the right way up..come to think about it, most footage I've seen of submerged airplane are the right way up.