Air France jet missing over the Atlantic

[John Golin]

I miss-spoke. Air Florida was not the accident I was referring too, the correct name escapes me,

I believe it was ValuJet... I think Air Florida was the flight that crashed in the Potomac.

[Dominic Manzer]

"I didn't know it was possible to send text messages through the maintenance-data transmission system(s)."

Yes, messages can be sent in both directions. This system was used on 9-11 to attempt to send a clandestine message to all pilots to take precautions. The intent was to alert the pilots without letting the hijackers now about the communication. The message to the plane that went down in Pen' was received before the takeover but was not read. It could have made a difference if it had been read. A plain speech radio message would have worked, but the status of each cockpit was unknowable on the ground and there is no why to broadcast to all planes at once.

As far as other modern communications, the passengers often have far better capability than in the cockpit. As 911 showed, cell phones work when over a ground network. If the plane is equipped with internet or cell phone support the passengers can get better wether information than the pilots.

The trains oceanic air control system is in dire need of updating. It is still done the same way it was in the 1940's, sometimes using equipment that was built for World War II. Manual positions reports, unreliable radio communications, no modern in cockpit wether. All of these have contributed to the uncertainty in this accident.

The cockpit is a difficult place to get new technology into. The FAA is reluctant to approve or mandate anything that will cost airlines money. Airlines do not want to change the cockpit without explicit FAA approval or requirement because of liability concerns. As a result, obvious safety improvements such as GPS have been very slow to get to pilots. I had a close call landing in Halifax when the pilot (the Chief pilot for the airline) found out the airport was well below minimums by landing. The GPS receiver I had with me would have made that landing much safer. I could not see forward, but i think we nearly landed in the bushes to the left of the runway.

[Dominic Manzer]

I miss-spoke. Air Florida was not the accident I was referring too, the correct name escapes me,

I believe it was ValuJet... I think Air Florida was the flight that crashed in the Potomac.

Thanks John, I should not have made that mistake as I happened to be in DC for the first time that terrible day, 26 years ago.

[Qavion]

Further info about text messages.

Our airline has 2 types of message groups:

FLT DISPTCH and MISC MSG's

Text messages of up to 2 pages long can be sent to "Flt Dispatch" for flight ops type of messages. These messages are addressed to one destination only.

The MISCellaneous MESSAGES menu also allows 2 pages of messages to be sent, but a 7 character address must be typed in. Our maintenance control centre has it's own unique address.

Ground stations have the capability of uplifting messages to the aircaft (if it's unique address is known).

Cheers.

Q>

[CarlBB]

So just one other thought (thinking out alond here)

Is there a system where say in addition to storing data on the black box, that there could be a reduced stream of data being transmitted 'somewhere'.

Not sure if transmitting and storing lots of data would be practical?

Carl

[Jeroen Hoppenbrouwers]

There is, they do. It is called ACARS.

Now, truly, it isn't ACARS as that is the transport network used to relay the messages. But most airlines have onboard diagnostic equipment, sometimes part of what in the 744 is called the CMC. Typically at predefined moments and when unexpected things happen, this equipment sends a datagram to home base. Routinely, engine performance data at T/O thrust is being sent to engineering, to add to the statistics and monitoring database and help in selecting engines for overhaul or adjustment.

I once was on the flightdeck of a Lauda Air 777 over Indonesia, chatting with the F/O, and he showed me around the system a bit. On the ND, using the 777 mouse pad, a complete health monitoring centre appeared. As he said: "If one of our engines turns a little rough, the guys in Vienna know it immediately. We as pilots don't know it as it won't break through the "need to know" limits of the EICAS. We won't be able to fix it anyway and it doesn't influence any decision we might make. But in Vienna they know, and technicians will be standing at the gate to fix it."

On top of these airline-specific diagnostic systems, there are reporting systems for estimated arrival time, weather reports (usually winds and temperatures), and automatic dependent surveillance aka ADS-C aka frequent automatic position reports. Well, basically what you see at www.hoppie.nl/acars/system/log.html

It depends on the airline what they have installed, but a modern A330 plus a large carrier makes for a pretty good chance that these money-saving systems were available.

And they received six messages in about four minutes time, complaining about problems. Irregular, but not deadly. Then suddenly the last, aborted message about cabin altitude and electrical failures. And never a word from the pilots, not even one desperate "mayday" call. So what hit them, must have been pretty sudden and pretty heavy.

Portuguese TV broadcasts reports of seven TAP flights that were in the same general area at the same time, and the pilots are pulling their hairs out as they experienced nothing, zilch, zero problems. Either we face an invisible thunderstorm that ripped the plane apart in a few minutes with pilots fighting for control, or the plane was already crippled by something else and then went into a thunderstorm to finish it off, or something.

Wait... we have to wait...

Jeroen

[Phil Bunch]

Yet another theory regarding the loss of the Air France airliner.

http://online.wsj.com/article/SB124411224440184797.html#printMode

This time this news source is quoting Airbus people as being concerned about excessive air speed and perhaps iced up pitot tubes due to electrical failures.

Here's an excerpt:
======================

"The developments in the investigation into the crash of Air France Flight 447 come as Airbus prepares to issue guidance reminding airlines world-wide to follow pre-determined procedures when pilots suspect their airspeed indicators are malfunctioning, according to these officials. The Airbus announcement, expected to be released later Thursday, would be the first specific indication that investigators suspect problems with airspeed indicators could have been the first stage of a cascading series of electrical and mechanical malfunctions aboard the packed Airbus jetliner."



"Under this preliminary scenario -- which is still developing and could be altered after further analysis -- airspeed sensors called pitot tubes may have iced up as the plane flew through a ferocious thunderstorm that could have included hail and violent updrafts, these people said. The devices, which have redundant features and are supposed to be heated, are the primary way pilots know how fast their aircraft is flying."

=====================

[Jeroen D]

There was a small news items this morning on Dutch radio; it appears that the authorities are now considering it might be a terrorist attack after all. They base this on the very large area in which debris seems to have come down, and large patches of unburned fuel found on the ocean.

let's hope they are able to salvage the FDR and voice recorder soon.

Jeroen

[Jeroen Hoppenbrouwers]

A strong argument against a terrorist attack would be that no organisation has loudly claimed success in the war against whatever.

[Peter Lang]

A strong argument against a terrorist attack would be that no organisation has loudly claimed success in the war against whatever.

Did somebody claim success after Lockerbie? As far as I rememeber, they said, they would not have known about the bomb on board, if the plane exploded over the sea and all would have sunk.

What still confuses me is, that the debris they found is far south of the last report on the south side of the thunderstorm. The aircraft was northbound and about to leave the storm cell.
http://www.avherald.com/h?article=41a81ef1/0004&opt=0
  -> satellite image from 2:45 UTC

Today the german Spiegel http://www.spiegel.de/panorama/0,1518,628677,00.html says, the debries found is not from the missing Air France A 330. They had no wooden pallets on board.

Peter

[Shiv Mathur]

.. it appears that the authorities are now considering it might be a terrorist attack after all. They base this on the very large area in which debris seems to have come down, and large patches of unburned fuel found on the ocean.


Jeroen

I don't understand.  How do these factors point to a terrorist attack ?

[Shiv Mathur]

What still confuses me is, that the debris they found is far south of the last report on the south side of the thunderstorm. The aircraft was northbound and about to leave the storm cell.


Today the german Spiegel ...says, the debris found is not from the missing Air France A 330. They had no wooden pallets on board.

Peter

Which makes me wonder, could it have been a mid-air collision ? And the debris is from the other aircraft?  This might answer both of Peter's points.

Of course, this would mean that there would be two planes reported missing ...
unless ...

[Peter Lang]

Hi Shiv,

Yes and also the debris of both aircraft should be within a relative clear range.

A mid air collision occured several years ago, at the african coast with a German and an US military aircraft. What I remember is this: they said the weather satellites noticed a light flash of that explosion.

Perhaps this time a possible explosion (if there was one) could not be seen by satellites due to the heavy thunderstorm and lightnings around.

The problem now is we have very sparse facts:

- Crew did not send emergency calls.
- Automatic generated failure reports of aircraft systems.
- Other crew saw orange parts on the water surface which they could not identify
- Other crew reported white flash of light going down, no lighning (meteorite?)
- Other crews reported weather not worse than usual.
- Debris found far away from last automatic system report (which probably also transmitted the position) almost in opposite direction of their flight path.
- Debris turns out not to be from the missing plane.

I have to admit, that this informations leave a lot of questions and some space for speculation and conspiracy theories.  But this seems not to be very useful.  It does not clarify or solve anything. It only feeds emotions.

Hope they find the parts, we all want for an answer.

Peter

[Jeroen Hoppenbrouwers]

More noises about failing airspeed indicators pop up, and reports about having received not less than 24 failure messages before everything stopped. Apparently the A/P was not engaged at the final failure moment.

[CarlBB]

There is, they do. It is called ACARS.

Now, truly, it isn't ACARS as that is the transport network used to relay the messages. ....

So I don't want to appear stupid (that would be first!)

But would the ACARS message/ Do the ACARS messages always include a GPS position in the message, regardless of the nature of the message that is transmitting?

Thanks

Carl

edit: sorry I am being stupid - I see on AVHerald on the picture it does say Last ACARS position report.

[Will]

Assuming that we're moving closer to the day when bandwidth isn't an issue, why not send as much information as possible back home?  You could basically create an off-site backup of the plane's black box back home in Toulouse or Seattle.

Will

[Jeroen Hoppenbrouwers]

Bandwidth isn't an issue if you have copper or glass fibre lines, or nearby high-frequency network towers. In the middle of the Atlantic, bandwidth is surprisingly scarce. Satellite links can carry a lot, but each plane needs to share in the link capacity.

What probably is possible is to not have a continuous open channel with bulk data, but to allow for sudden data bursts the moment something breaks. Such a system would not catch a midair collision or explosion, but it could help with the reconstruction of a chain of events.

[Jeroen Hoppenbrouwers]

But would the ACARS message/ Do the ACARS messages always include a GPS position in the message, regardless of the nature of the message that is transmitting?

Not all, but the cost of doing that would be relatively low (just a few bytes). Don't forget that ACARS itself does not include many message format/content guidelines. It's nearly all up to the airlines themselves. Many will have included these position reports.

What is "an ACARS position report" in the Air France case is not clear. There are ATC-over-ACARS systems in regular use, but they are not necessarily continuous.

[Jeroen Hoppenbrouwers]

I'm now reading reports that they picked up two bodies and material that could be nearly impossible NOT to come from the Airbus.

[John Davis PC]

Apparently the A/P was not engaged at the final failure moment.

If this turns out to be another one of the A340 inflight autopilot upsets, then Airbus could be in for a massive lawsuit !

I believe the other incidents happened in good vis and daylight, maybe if it happened at night in a thunderstorm it was a different story