I think you'll find caveokay was talking about having and an AP and an ATH engaged, not both APs.
Ah those traps in the English language...

But the reponse to CAT by the AP and ATH would be interesting, if somebody can give a reasoned description.

Never having experienced CAT apart from "cobblestones', never the full 'upset' ... can such an 'upset' be a brief and violent event (negative G and all that) after which you get to sort out the damage, or do you find yourself systematically 15,000 ft lower... with a little help from the AP?

CJ

IIRC, the Qantas briefing uses the words "It is a Qantas requirement ..." The emphasis reflects that in the video soundtrack.

Not that it makes the blindest bit of difference. Too many SLF just ignore everything said on the video anyway.

Why did the aircraft not continue to Perth where there are better medical facilities to treat crew/passenger injuries?

It seems crazy to land at a small town then have to fly some of the passengers on to Perth with the Flying Doctor Service.

In any case, best wishes to all involved.

it's called triage.

Any way you look at it from the ground it's second guessing. Tough decision in the air as a commander who has to rely on info from the cabin.

Perth would have been some 1100 Km further south, which would have meant an hour and a half more for injured passengers without proper medical attention. Better get them on the ground & stabilized and transported later if needed, I guess.

Acceleration limits??
 

What would be the general consensus about positive/negative G figures encountered going from say mild turbulence to CAT??

I had quite a similar case when flying from Bogota to Paris CDG: all at ounce, during 8-10 seconds, my A340 encountered really huge CAT.

I was Captain on this flight and my wife chief purser...:cool:

It was a night flight, weather forecast on route OK, but very far from my route, there was a heavy tornado.

I felt weather was too calm, when my chief purser told me that all passengers were eating, and then I switched fasten seat belts on, "just in case".

Then happened this incredible CAT I had never met during my 17000 flight hours.

Happily I had only three injured flight attendants.

If seat belts signs had not been swicthed on, I am quite sure I would have landed at Fort of France or Pointe à Pitre, with dozens of passengers very seriously wounded, or even worse.

Two of my three injured cabin crew lost their medic after that flight.

Here at the Towers we'd urge very, very careful reading of the brief formal communications from both airline and investigating authority.

The wording is such that we suspect that the aircraft might have taken a cascading trip down through its control laws. Airbus people might want to revisit those quotes earlier in this thread and also the original statements from their primary sources.

Interesting to consider the potential effects of a multiple referencing failure rather than CAT.

Rob

Dear Passengers:

You pay my salary, so thank you. But all this about seat belts, trolleys on tracks and that stuff...PUHLEASE:

I've seen PASSENGERS complain about keeping the seat belt sign illuminated. Some disobey the sign and go to the lavatory.

I know of one case in which a 737 hit CAT...the SEAT BELT sign was illuminated...one passenger got up, went to the Lavatory and was thrown violently around BECOMING A QUADREPLEGIC (sp?). GETTING out of your seat with the SEAT BELT sign illuminated also presents a DANGER to the crew and passengers.


Trolleys on tracks...hey great idea...I thought of it over 20 years ago and someone probably had the idea 20 years before that.

So, you want a flight like that...fine, let's triple the price of your ticket.

ON every airliner in the USA there is a sign in front of YOUR face saying to keep seat belt fastened while seated.

I've had FA's get on the PA after I had told the FA's to remain seated telling passengers to get back to their seat in violent turbulence.

PORROHMAN:(and sorry for the mistake earlier) thank you for posting the bit about coffin corner. I know ATP airline captains who really don't have a clue about this. I know airlines who , when given a choice between the 1.25g and 1.375g buffet margins, always tell pilots to go to the 1.25g so the plane can go higher and save fuel.

I have no problem with QANTAS, but I would like to know if there has been any change in buffet margin use and the like.

I am not at all surprised to see NO ONE IS commenting on the bit about watching outside air temps as a clue for CAT. Very few pilots know about...or I should say, MODERN and YOUNGER pilots.

Good advice there Rob!

It has been a while since I flew the A330 but there used to be a procedure that preset some of the flight controls if elevator redundancy was lost.I think it preset the ailerons upwards to counter the pitch up.The pitch up could be quite alarming when you had a subsequent failure.At high altitude you would rapidly be into a stall if you didn't react quickly enough.
I also remember an A340 I think it may have been an SQ one that did a similar manoeuvre when the crew switched off some of the hydraulic pumps when they were trying to balance the fuel!

You cannot imagine how devastated can be the aircraft cabin with trolleys wine and food flying around.

Nothing to do with the aircraft type I am not so found of.

In my experience flight crew pay more attention to the needs of cabin service rather than the less frequent need to restrain passenger movements, so sometimes we get bitten hard!

QANTAS have their FMC's pinned at 1.3g.
You fly attitude in severe turbulance. (airspeed tape usually impossible to read in severe turbulance anyway)
I have never met a QANTAS pilot not aware of the temp drop crossing a jetstream and the implications entering from the cold to warm side we are always crossing them at close to 90 deg. due route structure. (have yet to find a way of 100% compliance of seat belt sign!)

:ok:manrow, you are right.

But my wife executed my orders....Not like at home.:ouch:

Trying to fly attitude in an Airbus fbw aircraft is very difficult in normal law as you are commanding a pitch rate.
If the crew had made a poor response the aircraft may have gone into this mode:



ABNORMAL ATTITUDE FLIGHT LAW
A completely different law emerges automatically when the aircraft is in an extreme upset as follows:
* pitch attitude > 50 deg nose up or > 30 deg nose down
* bank angle > 125 deg
* AOA > 30 deg or >-10 deg
* speed > 440 kts or < 60 kts
* mach > M0.96 or < M0.1
The abnormal attitude law is:
- PITCH ALTERNATE with no protection except LOAD FACTOR protection. No automatic pitch trim.
- ROLL DIRECT with full authority
- YAW ALTERNATE
After recovery the flight law reverts to:
- PITCH ALTERNATE law
- ROLL DIRECT law
- YAW ALTERNATE
The aircraft returns to a degraded mode (not normal law as usual) because there is a certain level of suspicion about its ability to control the aircraft (that is how could it have got to the extreme flight state in the first place? The protections should have intervened well before the pitch, bank, AOA, speed and mach limits above).


There was a similar incident in the North Atlantic a number of years ago when an A340 had a speed upset and rapidly departed its alloted level.

Pan or Mayday?
 

I have "Mayday"ed twice; once because the smoke coming up the windscreen persuaded me that I was on fire, and the second when I saw so much smoke from a trawler below that it seemed to be on fire.
Technically I should have "Mayday"ed only in the first case as it was "my" aircraft that seemed to be in immediate danger.
The trawler justified only a "Pan", it seems. However the RAAF people were not censorious.
No fire; only smoke in both cases. But who knew?
thekite

dear modest pilot:

thank you for that info...the only QANTAS pilot I know of is John Travolta...and I'm sure everyone at QANTAS is better than him.

I respect QANTAS and I'll bet you and I think alike.

When I mentioned the temp thing, I meant it for the other 90 percent of people on this website.

I have a feeling that the crew is not to blame and either a computer glitch or a real doosy of CAT.

mermoz92, thanks, you answered several of my questions, if only implicitly.
As an engineer, I don't think it would add that much weight, hence not that much to the price of your ticket.
Look at the seat rails, which IIRC already are supposed to take 15G?

Replace the underfloor stiffeners in the aisle(s) with trolley rails integrated in the structure. Would need new trolley wheels, probably in titanium to take the stress.

I doubt it'll happen, not because it can't be done, but the logistics of the changeover would be horrendous.

And CAT and flying trolleys and injured CC and SLF are (thank goodness) so rare that they still make the 'media' and even PPRuNE, which in itself signifies it's not exactly a common occurrence.... so nothing will be done about it.

Yes I'm a cynic, but also realistic....

"TO ALL PASSENGERS . . . have a plan...IF I HIT BUMPS NOW< WHAT AM I GOING TO DO?"

If a passenger is caught out of his or her seat during severe turbulence, the passenger should drop to the aisle floor, hook an arm through the framework of the nearest seat, and hold hands.

It would not hurt to toss that into the safety video as well.