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You do realise the pitots are heated right?

If pitot heat is turned on, yes.

So yes – while the ice remains the readouts will be faulty. (I dunno where your running with the expansion idea – the various pitots will all be reading different, i.e. wrong results – the computer will still be in alternate mode)

Because it’s happened before -> http://en.wikipedia.org/wiki/Birgenair_Flight_301 – if you read the report into that accident you’ll see that that Captains pitot tube was blocked, as the aircraft climbed the air trapped in the tube expanded due to the outside airpressure dropping. The captain believed this to be a true IAS reading and stalled the plane. The co-pilot had a perfectly working pitot tube and correct IAS readings. They still crashed.

However, instead of dealing with supercooled liquid at 35 kft, by dropping down to 10 kft you will clear the ice and you will have working pitots.

You will also have avoided stall and kept control of the aircraft – which is (or should be) rule no. 1.

I’m sorry but there is no basis for fact in that. Super cooled liquid water is a theory and not a fact. Also, by dropping 10kft you may well make the problem worse with less room to deal with the issue. Personally I always like sky below me – it can be useful if something goes wrong.

Rule number 1 is ‘fly the airplane’ which I’ll agree that AF447 pilots did not do but it was a confusing, strange situation that few pilots are trained for. It was dark and there was no horizon. Probably one of the worst situations to have problems in.

Pull the other one if you think sustained descent isn’t going to de-ice the probes.

Why would it? in fact, it could make the problem worse as air trapped behind the ice expands in the tube and provides even more confusing information to the aircrew.

or don’t know how to heed it. Go back to AF447, dark and stormy weather, the weather radar is full of red, the aircraft is bumping around suddenly you get multiple ECAM warnings, including two key ones about stall protection and pitot tube issues and in the middle of all that the autopilot says ‘I have no idea what I’m doing, I’m off to the pub – you fly it’.

It doesn’t matter what safeties are in place when the computers decide that the pilots should fly and for those few moments that must have been one frighting situation.

Look at the Qantas A380 uncontained engine situation, it took the crew two hours to action all the ECAM warnings and even there were a few that were mutually exclusive. The crew found that when they actioned one it brought up another alert, when they actioned that alert the first alert came up again.

Again, a frightening situation but because of the nature of the problem the crew were able to work it.

Don’t forget that AF447 went from normal law to alternate law and there is no stall protection under alternate law. Personally I believe that this is the major issue with AF447, the co-pilot pulled back on the stick because, quite rightly, you can’t stall an airbus unless it’s no longer flying in normal law. Of course, in times of stress its easy to forget that.

There is a wonderful video shot in 1997 about how pilots are too dependent on automation:

http://www.youtube.com/watch?v=h3kREPMzMLk

hmm, flightradar on twitter has this to say:

Squawk 7700 (general emergency). G-EUUJ (British Airways A320) from London to Glasgow http://www.flightradar24.com

So something happened, maybe pressuristation if it had that fast a dive?

I’m sure something will show up on the AAIB site at some point in the future if its serious enough.

Absolutely and I agree about the simplicity of the questions which is why I never went further than the first page.