Yesterday an Air France Airbus A330 crashed on a flight from Rio de Janeiro to Paris France. Basic details of the accident can be heard on the news cast on the following site and the following article
The Airbus is manufactured in France and has been in operation for over 15 years. Something unique about the Airbus A330 is that the pilot controls inputs to the control surfaces by wire. Each pilot has a control stick that is moved to put electrical inputs into the computers which in turn make the input changes in the aircraft control surfaces. The writer of this article is familiar with some of the basics of an Airbus but not the actual systems. From what the writer knows the Airbus A330 is controlled by either 5 or 7 computers. Obviously the computers are very important and they would have backup electrical power systems. However Airbus has had some issues with computers in past models with several computers failing at one time.
Assumptions by the writer:
Turbulence: This could be a factor causing possibly a computer failure from severe turbulence or engine failure. Some aircraft have had compressor stalls in the engine with severe sudden turbulence. This area of the world is known for very large storms that can have tops in excess of 60,000 feet. It is also possible that the aircraft may have had structural damage from severe turbulence that could lead to the breakup of the aircraft in flight.
Lightning Strike: Aircraft are designed to handle this kind of occurrence and many times an aircraft may be struck by lighting and the flight crew will not even know it. Discovery would likely be a small chard area on the fuselage of the aircraft. It is remotely possible that a lighting strike or multiple lightning strikes may have caused a computer failure or some other structural problems. Want to see some lightning images click here.
Mechanical Failure: It is also possible that the aircraft had a mechanical problem. Mechanical causes of aircraft accidents are rather rare and account for less than 10 % of all aircraft accidents.
An investigator would also not want to rule out terrorist activity, bombings and other external factor that could also be a factor in any airliner crash. What will make this crash difficult to discover the cause is the depth of water the crash occurred, the large area to search for the crash and the black box will only ping so long after the crash until the battery goes dead. The fact the aircraft was flying in the oceanic system without radar tracking and making position reports at least every 60 minutes will also leave a large search area.
Aircraft Statistics can be found at the National Transportation Safety Board web site.
Manufacturer information about the aircraft can be found at Airbus web site.
What can an instrument rated pilot in general learn from this crash. Flight into an area of weather should be performed with great caution. We as pilot become complacent in the fact that many times over a career of flying we may have flown into areas of weather and have used radar to fly around or even threw cells within a thunderstorms. What we cannot predict is what the weather is really like in a storm until we are in the weather. Let me point out in my career of over 25 years of flying I have only once flown into an area of unknown severe turbulence that lasted for approximately 15 seconds. It seemed like a several minutes and when you put an input to turn left and the aircraft goes right this is not a good thing! I would describe the turbulence event as Severe to Extreme Turbulence. Lets review the Airman Information Manual definition of Turbulence:
Light Turbulence: Turbulence that momentarily causes slight, erratic changes in altitude and / or attitude
Moderate Turbulence: Turbulence that is similar to light turbulence but greater intensity. Changes in altitude and / or attitude occur but the aircraft remain in the positive control at all times. It usually causes variations in indicated airspeed.
Moderate Chop: Turbulence that is similar to Light Chop but greater intensity. It causes rapid bumps or jolts without appreciable changes in aircraft altitude or attitude.
Severe Turbulence: Turbulence that causes large, abrupt changes in altitude and / or altitude. It usually causes large variations in indicated airspeed. Aircraft may momentarily be out of control.
Extreme Turbulence: Turbulence in which the aircraft is violently tossed about and is practically impossible to control. It may cause structural damage.
Here is a video described as Severe Turbulence which by definition should only be Moderate Chop Turbulence.
In this video the runway stay relatively in the same position with small corrections to the aircraft going on during the approach. Not to down play that the flying conditions are not the best in this video but the fact someone could even video tape the event would make it moderate turbulence. Now imagine momentarily loosing control of the aircraft this close to the ground with abrupt changes in the altitude and the attitude! A pilot would not be able to fly and land an aircraft in sever turbulence without significant risk of severe damage to an aircraft on landing. I have flown approaches in turbulent weather with up to + 30 knot wind shifts in remote areas of the world and bank rolling up to 15 degrees. I would not recommend it, it takes skill, above all staying well ahead of the aircraft, a two man crew with one calling airspeed while the other concentrates on flying the aircraft on the approach and above all maintain power spooled up ready to go around. I personally would not even consider taking the chance of flying a visual approach to landing in severe turbulence. Robbie Johnson Chief Pilot
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