Air France A330-200 missing

[FMC]

Just read that AF have released further information on the ACARS traffic :-

02:10Z A/P disengaged and a fault with one of the FBY computers.
02:11Z - 02:13 Faults in the NAV system was reported in a flurry of messages. Then a fault reported in a system that provides instrument readings (IRU?)
02:14Z Fault reported in vertical cabin speed giving rise to decompression of cabin.

ends

FMC

[Diver-BR]

The US Navy recovered the UAL 811 cargo door about 20 years ago from a depth of over 4300 metres, and seeing that did not have a pinger, recovering the black boxes is not so unlikely.

One of the additional challenges faced by the investigators is that the ocean floor is very uneven where the AF was lost, it is part of an underwater mountain range. I agree that there's no guarantee of recovery of the recorders.

[Dutch Bru]

Brazilian airforce: update press release 15:10 GMT

PRESS RELEASE 03/06 (1015 Brasilia time) Brazilian Air Force:

"REPORT OF THE SEARCHES OF AIR FRANCE FLIGHT 447

The Air Command announced that during the searches conducted during the early night and early morning (03/06), an R-99 aircraft of the Brazilian Air Force (FAB) identified at 03h40 (de Brasília time), plus 04 (four) points of wreckage, 90 km south of the region originally covered by aircraft of the FAB. The crews of the R-99 observed the following provision of the items found:

- Various objects scattered in a circular area of 5 km radius;

- 01 (one) object of 7m in diameter;

- 10 (ten) objects, and some metal, and

- Oil stain with extension of 20 km.

During the morning, five other military aircraft take off from Natal-RN into the area of search, and three (03) C-130 Hercules in FAB, 01 P-3 Orion of the U.S. Air Force Falcon 50 French and 01 the opportunity where they go each point identified by the R-99 aircraft in order to obtain more information of the objects detected.

In total, eleven aircraft are deployed from the Natal and Fernando de Noronha Airbases to perform the search.

Five of the Brazilian Navy ships are sailing toward the area of search, with estimates of arrival of the first one (patrol vessel Grajaú) this morning. 03 merchant ships of amongst others Dutch and French nationality have arrived in search of the place of yesterday evening and will assist in the recovery of wreckage found at sea.

The Rescue Coordination Center in Dakar reported the closure of operations for searching the Dakar FIR. However, Dakar continues to contribute to the search operation in Brazil, with the coordination of AWACS aircraft (aircraft radar) of the French Air Force, flying over an area within the limits of that FIR with FIR Atlantic (Brazil), in search of objects on the surface of the ocean."

[wileydog3]

What is the power source for the ISIS? Does the loss of ISIS along with the ADIRU fault and the reversion to ALT Law indicate a total loss of electrics?
(yes, I know the process is Normal to Alternate to Direct and then with all loss the THS, rudder and FADEC engines. And yes, I understand we are talking loss of both eng generators, no APU, a failure with the RAT and loss of battery power)

Most standby inst packages I have flown were independently powered.

Cause unknown but are we talking about an electrical fire that quickly took out all instruments as well as flight control computers? We saw in Swissair 111 and ValuJet that inflight fires can evolve VERY quickly offering little time for a solution and rapidly diminishing control.

[learjet45]

I think some on this thread may be over analizing with their speculation and of the technical chatter. IMHO this accident appears to be nothing more than a series of events that led to the structural break up of the A/C due to weather....."exceeded the structural limitations of the airplane" as they say, by possibly flying blind into a very hairy area of that storm system. I have visually put myself in their predicament many times since this happened (although I'm not familiar with the Bus) and each time I've had a serious case of goosebumps. Everything went to hell very, very fast it appears. This flight will def be in future sim rides for many of you I'm sure.
Methinks we'll never know exactly what happened without the FDR and the crew will be blamed, of course. Wrong place at the wrong time.

[Lost in Saigon]

Much importance has been attached to the following:

at 02:14Z the last message received was an advisory regarding cabin vertical speed.

One very important piece of information is missing though. Was the cabin vertical speed indicating a climb or a descent?

If there was some form of explosive decompression it would of course be a climb. But the cabin cabin vertical speed advisory was the LAST in the sequence of advisories. That could easily be interpreted to be that the cabin was intact and pressurized during the descent to the water. It was only when the cabin descended below the altitude of say 8,000 feet that we would then see a cabin vertical speed indicating a rapid descent rate.

Does anyone know if the "advisory regarding cabin vertical speed" was a positive or negative value? And what was the actual rate of change?

[win_faa]

learjet45

Methinks we'll never know exactly what happened without the FDR and the crew will be blamed, of course. Wrong place at the wrong time

When an accident of this nature occurs, if you don't pull out all the stops and bend every effort to establish what the cause of this accident, then the airline industry is going to get another accident cause by the same thing.

[RatherBeFlying]

55 miles between debris areas

http://www.nytimes.com/aponline/2009...zil-Plane.html

A 23-foot (seven-meter) chunk of plane and a 12-mile-long (20-kilometer-long) oil slick were found early Wednesday, Brazilian air force spokesman Col. Jorge Amaral said. Rescuers have still found no signs of life.

The new debris was discovered about 90 kilometers (55 miles) south where searchers a day earlier found an airplane seat, a fuel slick, an orange lifevest and pieces of white debris.

The location of the new debris is consistent with where experts say currents in that part of the Atlantic would push anything on the surface.

That's indicative that whatever broke off in flight contained fuel -- stabiliser or wing. The convective weather would play its part among previously mentioned factors in separating the impact points.

Unlike the 747 breakup off Taiwan, we do not have shore based radar tracks of the various trajectories.

[GlidingAerobats]

I believe that you can do that in either aeroplane, in theory. In a Boeing, you always have that privilege. In an Airbus, you can go to 'Direct Law' (I think!). But, also as far as I know, that means that you won't have elevators or ailerons to fly with, just the rudder and the trim controls.......

I think, there is a confusion here concerning "Direct law" and "mechanical backup". When introducing, the FBW-System, Airbus kept a mechanical backup for the stabilizer trim and the rudder pedals - like on conventional aircraft, these are connected with steel wires (The original fly-by-wire ;-)) from the cockpit control to the aircraft tail. You can hence still control rudder and stabilizer trim even after a complete loss of electrical supply or FBW computers. (Whether that is a nice way to control an aircraft, is another question.)

The "direct law" is a control law that the FBW-computers change into, if there is a certain combination of system losses. Direct law, means, as khorton already said, that the sidestick controls directly the aileron/elevator deflection - without any protections or load-factor/roll-rate law. Primarily this happens, when the computer cannot be certain of the correctness of the input data. (I.e. loss of 2 IRs leads to direct law, if the computer cannot automatically identify the second RU loss. (Source: FCOM A320, I assume, A330 is similar.) The crew can get back into alternate law, by resetting the Flight-Control computers after manually identifying the second defective IR.)

So, the easiest way to get into direct law is probably by switching off 2 ADIRUs. May have the "little" side effect of losing speed, altitude and attitude indication, though...

[benmac]

Flying through an ITCZ

All the talk in this thread of ITCZs, hard CBs and turbulence reminded me of a transit I made in a MK2 Vulcan in Dec 65 between Darwin and Singapore. I was flying at 56,000 ft and at the top-of drop for Singapore encountered an ITCZ that stretched from horizon to horizon with giant CBs still pushing upwards well above my altitude. The ride became somewhat hairy with the g meter fluctuating rapidly between + 3g and - 1.5 g and the aircraft shrouded in St Elmos Fires. However, the worst part was trying to descend to Singapore. The uplift from the CBs was so great that even with the throttles closed and full airbrake I could hardly get any kind of rate of descent and stay short of MNE (never exceed Mach ). Of course, at that height,the gap beween MNE and stalling speed doesn't give you much of a leeway. I could imagine an aircraft getting into serious difficulties if the pilot allowed the speed to depart this gap.

[Tail Chase]

Terrorist Theory

Since the question was posed a few hours ago and a terrorist bomb is still a possibility behind the loss of AF447, there was indeed a bomb scare on May 27 in connection with AF415, which was scheduled to depart from SAEZ that evening.

A late morning telephone call received at AF's offices in downtown Buenos Aires stated that the aircraft - which at the time was parked a few hours after completing AF418 - was carrying a bomb. Local police bomb squads performed a throrough search of the aircraft and found nothing, ascribing the episode as nothing more than a bomb hoax. The aircraft was released and it executed AF415 as scheduled.

In retrospect, one is led to think whether these two episodes bear any connection with each other.

Cheers

[Aerochti]

According to my AF maintenance source, the ADIRUs manufacturer of F-GZCP (AF447) is Honeywell.

[grizzled]

As I said waaayy back at the beginning of this thread: The odds are very much in favour of the FDR and CVR being recovered, not the other way around. Those who write that finding them will constitute "a miracle" are not up to date on current technology and methodology.

Yes, this will likely turn out to be an incredibly expensive investigation, but it will be done. Despite those on pprune who speak of conspiracies amongst the investigative agencies, and/or the manufacturer(s), the truth is that the incentives and rewards of a thorough investigation make it far more worthwhile to those agencies than any alternative.

grizz

[khorton]

I hauled the nose up to beyond the theoretical point of a stall, and managed not only to get over him, but actually to get the nose going down instead of up, theoretically beyond the certainty of stalling in, and land safely..........

......

So I guess I could have done the same thing in an Airbus? Just by remembering which half-dozen buttons to press, in which order?

In Normal Law you can get to the edge of the stall. There is no advantage to going beyond that, as even if you can get to higher angle of attack in Direct Law, there is no additional lift to be found, so no possible way to change the flight path angle. All you would do by manually going to Direct Law is give yourself the possibility to lose control of the aircraft.

I don't agree with every aspect of the Airbus flight control law protections (I would like the option to pull more than 2.5 g in emergency, possibly by pulling through a "soft stop", for example), but the limits on angle of attack seem very well founded in my opinion.

[spannerhead]

There's too many posts in this thread from people who think that they know the 330 from a technical aspect when quite honestly they haven't got a clue. A few posts back someone mentioned that the stabiliser has a mechanical backup........it doesn't! The 'steel cable' mearly positions a slide valve and hydraulic power moves the stab.

[Jo90]

Thought for the day.

Q.When is the most likely time to have a lightening strike?
A. When you're picking your way among a mass of Cbs (eg the ITCZ).

Q. Which part of your aircraft is most likely to be struck?
A. The nose.

Q. What lives in the nose (apart from you)?
A. The radar antenna.

Q. If that gets knocked out by a strike have you got a spare?
A. No.

Conclusion: At times like this always maintain a mental or written note of what headings you would fly and for how long if you suddenly lost the Wx radar.

[GlidingAerobats]

There's too many posts in this thread from people who think that they know the 330 from a technical aspect when quite honestly they haven't got a clue. A few posts back someone mentioned that the stabiliser has a mechanical backup........it doesn't! The 'steel cable' mearly positions a slide valve and hydraulic power moves the stab.

OK, maybe I was not precise enough. On any airliner sized aircraft, nothing goes without hydraulic power, that is clear. My point with the mechanical backup was to point out, that it is possible to control the stabilizer from the cockpit in case of total loss of electrical supply/FBW-computers. The same is of course valid for the rudder pedals. The rudder is of course also actuated hydraulically, but it is possible to actuate it directly without going through the FBW-computers.

I hope, this makes it more clear, what I meant? At no time did I mean to leave the impression that you could actuate the stabilizer in the absence of _hydraulic_ power. Sorry, if I wasn't clear enough in my first post.

[ribt4t]

There's too many posts in this thread from people who think that they know the 330 from a technical aspect when quite honestly they haven't got a clue. A few posts back someone mentioned that the stabiliser has a mechanical backup........it doesn't! The 'steel cable' mearly positions a slide valve and hydraulic power moves the stab.

Yeah I've been kind of amused by those posts myself. Also the ones that seem to suggest that the Airbus is the only fbw aircraft.

[Belgique]

Just a Coffin Corner Encounter?

Air France Flight 447 Crash Cause

Interesting compendium of emails on the AF447 accident.

Seems to suggest that a risk-taking approach to operations in coffin corner was an equally likely culprit. More likely than a lightning strike anyway. If so, it was possibly unwise to do that above a very active ITCZ at night.

Look out below. Tired crews with low awareness levels don't react very well when things suddenly come unstuck.

Cruise captains are likely to be not as well prepared for a sudden coffin corner encounter. The two seats might suddenly end up in disagreement on the appropriate recovery action (roll direction?). Or maybe (the emails suggest) the Airbus will have a third opinion as to which way the pilots "can" roll-out for recovery (rather than "should").

[TeachMe]

If the weather radar was taken out by lightning (or just failed) facilitating flight in to a storm cell leading to loss of control, would the first maintence text message not have been about the radar failure, not the autopilot disengaging?

TME