Coffin Corner
 

One extra bit, which I cannot remember to have been posted yet. With these prerequisites

• sea surface temperature was reported to be 27 - 28 degC, that is ISA+13.
• cruise speed M.82 (my assumption, to be corrected)
• weight approx. 210 t (took the same like snaproll3480)

the actual AF A330 QRM says for ISA+15

MAX AND OPT ALT FL357

ENGINE ANTI ICE ON -1100 FT
TOTAL ANTI ICE ON -1300 FT

Now, go figure what might happen when they had to

• manually fly with alternate law (hence without stall protection) in turbulent air
• tried to fix the assumed possible sensor icing (whichever) with total anti ice on...

MAX ALT would be reduced to FL344 (in clean air, that is), which means it was near impossible to keep the plane from stalling. Even if my numbers are slightly incorrect for the actual flight, the turbulences they encountered surely would have taken away every margin they might have had.

To me, this would be enough to draw the deadly picture.

theamrad
Both Aircraft B744 & A330 FADEC (EEC’s) Units separately develop their own independent air data information for use in engine parameter calculations.

They are not tied into the navigation air data system

Ok avspook - I knew that in the case of the 744 - just using the EICAS message as an example. So with A330 - loss of AD means no effect on FADEC and therefore no messages generated :ok:.

Above optimum altitude
 

There is much talk of this aeroplane possibly being operated above optimum altitude or in "coffin corner" but so far I have not seen any reference to the obvious remedy.

I refer only to a serviceable aeroplane here but if anyone finds themselves with insufficient thrust to maintain speed through turbulence when above optimum altitude or above severe turbulence recommended levels, there is always the option of descent.

If it is serious and immediate enough such that speed is decaying even with max thrust, forget clearances, forget everything except getting that nose pointing downwards, with appropriate max thrust, to recover speed. Turn off track; use TCAS; anything but get that speed margin back, pronto but by definition the margin to MMO will be very small initially.

If significant unserviceabilities are added to the equation, the problems will magnify hugely but the basic principle remains.

Question: Does anyone advocate or ever been taught to use speedbrake to recover from MMO exceedances? I have found conflicting information in certain manufacturer's training manuals. I see a benefit in using a rapid application of speedbrake against thrust in certain conditions and perhaps avoid speed then reducing too far with consequent lag in thrust application again.

BBB,

According to the ATC flight plan retreived from CFMU files, and which I have seen on another website, the filed speed was indeed M82.

I found the link to the image, here is it:

http://www.weathergraphics.com/tim/af447/flightplan.gif

One question.
Will an excessively high G load during flight trigger an ACARS maint. message?
Thank you.

I don't think anybody has gone directly after the crew. However after going back over all the officially/unofficially (acars info) released information it does seem that the press at least are being driven in one direction.

I cannot remember any accident where acars data was released so quickly even if as a supposed unofficial leak which has greatly upset Air France.
Even then the data is supplied from a search function in a company software database and clips off anything prior to the flight.

Considering maintenance performed prior to the tragic Helios, Spanair and Excel flights was made openly public I do wonder what maintenance if any was performed on this aircraft prior to the RIO-CDG leg and why nothing has been mentioned?

You normally get some sort of statement.

Will Fraiser-

Understood. (my earlier reply seems to have been deleted so I'll leave the commentary out.)

Would the A/P being on make any difference in the recommended use of A/T in sev/extr turb?
I seem to recall that the A/T systems in airbus' have an advanced algorithm for dealing with windshear & turb.?
Did/does AB and/or AF recommend leaving the A/T engaged for sev. or extr. turb.?

Safety Concerns

If I remember right, the original statements from Air France said that the last maintainence AF447 had was back in April. Nothing about anything done in Rio before the ill-fated flight.

hi all i have a question. i fly the 727 and when i am down to battery power the pitot are not heated . is this the same for the 330???? if so no wonder the computers got wrong information.

thanks

AP is reporting a memo from AF to pilots saying the airline is replacing pitot tubes on all medium- and long-haul AirBus aircraft with newer models within the next few weeks:

Air France says it's replacing flight instruments - Yahoo! News

Could there be a good possibility that the airplane may have gone down intact. I suggest this on the thus far slow or lack of discovery of a debris footprint. Had the airplane failed at altitude, given the altitude, speed, and winds aloft, then one could reasonably expect an extended area of debris which would track with the airplane as it descended. It would therefore be quite large, and I doubt it would have been difficult to locate.

To compare, I recall all too well the Lockerbie situation with the inflight breakup of PA and the area that was affected. The heavy portion fell in the village, and nearby area, but countless other items extended for miles. Some large, some small.

On the other hand, MS990 created only two relatively small debris field in the Atlantic. One 62 X 66 meters, and the other 83 X 73. This airplane entered the water mostly intact. Radar coverage made it quickly discovered.

>>> Request - Please Read <<<
 

It would be helpful to the readability and usefulness of this thread if posters would kindly refrain from quoting "newspaper", "news media", "Network XYZ aviation experts", etc theories on what happened to AF447. These articles and posits are highly speculative and authored by people that most likely have less knowledge of transport category aircraft operations than our cabin crew.

Your cooperation will assist in keeping this thread on at least a soft focus.

Reports of new information are of course most welcome.

AIRWORTHINESS DIRECTIVE

Airbus Industrie A330 Series Aeroplanes
AD/A330/1 Pitot Probes 12/2002

Background: The French Direction Générale de l’Aviation Civile has advised that operators have reported loss or fluctuation of airspeed when flying through extreme meteorological conditions. Further to an investigation, the presence of ice crystals and/or water exceeding the current limits of the initial specification of Rosemount pitot probes P/N 0851GR is considered the most probable cause of these airspeed discrepancies.

This Directive requires the installation of pitot probes meeting more stringent
qualification requirements.

Barry James Reid McKay

Delegate of the Civil Aviation Safety Authority
17 October 2002

http://www.casa.gov.au/wcmswr/_asset...0/a330-001.pdf

@vapilot2004 you are probably correct but replacement of all pitot probes and confirmed by Air France is relevant.

The article says the process has been "ongoing" and should be complete within a few weeks.

Therefore I expect one of the first questions tomorrow by a journalist to be "have they been replaced on AF447 and if so when?"

I will refrain from speculation until that question has been answered. However the manner and format of the acars messages is lets say non conventional.

Forgive if Im wrong but this directive regarding the pitot tubes is from 2002 and this plane we are talking about left Tolouse in 2005.

Altitude
 

One item I've not seen enter the discussion:

Based on the flight plan posted on Tim Vasquez' excellent discussion, the following jumped at me:

"INTOL/M082F350 UN873 SALPU/M082F370 UN873..."

Decoded, this means the flight intended to cross INTOL at Mach 0.82 and FL350, proceed along the UN873 airway and cross SALPU at Mach 0.82 and FL370. In other words, the canned flight plan called for a cruise climb from FL350 to FL370 between INTOL and SALPU and before disappearing.

Do we know if this cruise-climb was performed? If it was, would not the A330 have been even more deeply embedded into its "coffin corner?"

DCr

Correct, but perhaps the fix wasn't ...... a fix.

Actually, these presentations were available on the A306/A310 years before the A320 flew, right?

Well, by the time this plane was made that fix should hv been fixed. Airbus had three years to start using the new pitot tubes.