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AF 447 – The Rush to Blame the Crew

April 11, 2011 Comments off

AF 447 – THE LONG ANTICIPATED RUSH TO BLAME THE CREW
Air France decided to wait and see and now we have seen over 200 dead

Air France 447 was the arch typical confluence of a number of factors that figure in any aircraft accident.

The conditions were night out over the South Atlantic. The Tropical Convergence Zone, that area of our earth’s atmosphere where the Northern Hemispheric direction  of winds collides with the Southern Hemisphere’s opposite direction resulting in violent giant sized thunderstorms.

Other aircraft that night diverted more than 200 miles to avoid the worst of the storms that AF 447’s crew decided to penetrate.

The crew was more than amply experienced in the A-330 with a collective experience of some five thousand hours in that model.

What the crew could not have known is that Air France decided not to urgently replace even one of the pitot tubes with models less likely to ice over.

In short Air France made a choice to expose the crew and passengers to a serious risk of death or injury due to its decision to wait and see.

Air France did the same thing with its Concorde fleet by not installing safety measures to avoid penetrations of fuel tanks from exploding tires. That decision was responsible for the only fatal accident of that aircraft taking 100 people with it.

As the Airbus made its way towards a line of level five and six thunderstorms, the aircraft was manned by an experienced first officer and a less experienced junior FO. The Captain was in the back.

Shortly after entering the weather, airspeed was lost and the autopilot disconnected. This should not have caused loss of the attitude indications but no doubt generated many warnings and messages.

The pitot tubes iced over and then deiced and then iced over wreaking havoc with the aircraft computers and messages.

The aircraft was in cruise at the time so nothing should have changed to result in the loss of the aircraft.

Soon however the aircraft began gyrations that were the stuff that horror films are made of. Sudden pitch ups and downs, engines to idle to takeoff power, altitude changes culminating in as much as a ten thousand foot per minute descent to the ocean below.

Nearly two years after the crash, the flight data and cockpit voice recorders were discovered and recovered.

The vertical stabilizer was found six miles from the main wreckage.

The data which everyone agrees is false because of the pitot tube icing has been pieced together to conclude that the cause of the crash was the flight crew putting the aircraft into a deep stall that resulted in a rapid descent in roughly level aircraft attitude nose up precariously with takeoff power while they watched themselves crash speaking a translated French gibberish that no flight crew would ever speak like under the circumstances.

Let’s see now, an experienced flight crew in cruise with the aircraft all trimmed up for level flight pitched the aircraft nose so high that the aircraft not only stalled but went further into the never never land regime of deep stall.

Then with a working set of attitude instruments the three of them (the Captain returned to the cockpit during the descent) didn’t realize what was going on, couldn’t regain control of what the French say was a perfectly intact aircraft and then died along with their passengers no doubt while humming the Marseillaise.

I would like to suggest that what has been written by French authorities is totally and absolutely wrong and I can think of a few French epithets the crew would be hurtling their way if they had lived.

First, no mention of whether Air France dispatch told the crew to avoid the area of increasingly serious weather or if they had put on enough fuel to divert the necessary hundreds of miles.

Second, no mention of the limitations of the on board radar to provide adequate penetration information or whether the flight should just have been cancelled due to an impenetrable line of weather that no aircraft should enter.

Third, no mention of how fully stalled an A-330 can possible develop a ten thousand foot per minute descent rate which is the rate one sees with an aircraft that has already lost critical parts in flight.

Fourth, no mention of a “G” tracing to see how beat up the aircraft got when it entered that line of thunderstorms.

Fifth, why did the computers not have a remedy for the crew when deeps stall is a flight tested regime?

Sixth, why is this the second A-330 with a composite vertical stabilizer that has crashed with it separated from the main wreckage?

Seventh, when was the vertical stabilizer lost and did the aircraft Split S or knife edge down because it was gone and that maneuver cause the high descent rate?

Eighth, why don’t any French investigators know how to translate French into English expressions that explain what the crew was doing during the descent.

Ninth, why didn’t Air France replace at least one of the pitot tubes with the non-icing type before losing an aircraft and its crew and passengers instead of waiting to see what would happen if they did nothing?

Now at the end of the day this crew will be blamed by the French Government because it would be a sacrilege for the French to blame their home grown aircraft industry or their national airline for anything but unless they get serious the world aircraft industry will become increasingly wary of the legitimacy of the investigators’ conclusions.

The crew should never have tried to penetrate that line of weather.

The airline should never have dispatched the aircraft in that weather.

The radar was no doubt attenuating such that the crew could not see just how bad the weather was.

The pitot tubes should have replaced at once since the aircraft could not fly as certified and thus was not airworthy.

The concept of deep stall should have been annunciated by the computers and a suggested resolution made as it is an easy flight regime to recover from but engine power must be reduced to idle and the nose dropped well below the horizon which is contrary to what is trained for.

The vertical stabilizer must remain on the aircraft for the duration of the flight, period!

This investigation relying on admittedly invalid data is a sick portrayal of why Government aircraft accident investigation aided by manufacturers and airlines worldwide doesn’t work and why “Dead men tell no tales.” is still the standard that conclusions of probable cause are improperly measured by.

Arthur Alan Wolk