Alizée America Forum - Air France Flight 447 crash

I work for an airline and I always follow stories like this closely. One has to because like the saying goes if you forget histories mistakes, you are doomed to repeat them.

There have been reports that there were inconsistencies in the air speed readings. This is very crucial to a plane. Years ago a Boeing 757 crashed into the ocean after taking off, I believe from South America, with static ports taped over. Static ports are small holes on the side of the aircraft used to sense ambient pressure. These are crucial for accurate air speed readings. Apparrently someone had taped them over when washing the aircraft, then forgot to remove the tape. All this caused was wrong air speed readings. The engines and the rest of the aircfaft was working perfectly well but because the pilots couldn't tell how fast they were going, they lost control. Nobody survived this crash.

Typically in most commercial airliners, you have three air data systems ( air data meaning air speed, altitude and vertical speed) that work off air pressure. The pilot's, first officer's and a back up. If either one acts up, you can switch to the alternate. They can even tell there ground speed through the satellite navigation system (gps) too. Occassionaly one goes bad, usually caused by a leak in the system, but the systems are independent, so you can usually quickly figure out which is the wrong reading and switch to the backup.

These probes are heated to prevent them from icing up. With most of these aircraft, these heaters are left on throughout the flight. They are very reliable and they are monitored by computers which will warn the pilots when they're not working.

There were several other problems reported by the aircraft also.
Within the U.S., airlines use a radio that automatically sends out information every 15 to 20 seconds. It's just like the 2 regular radios used for voice communication. In fact you can tune one of the radios to the data frequency and you'll hear a quick chirp which is just a high speed burst of digital information being sent out. Unlike a flight data recorder which is regulated by the government as to what it records. I believe the info that is sent out by the data radio is strictly up to each operator (that may change now). It can be used for monitoring the condition of an engine. Typically if a plane is cruising along at 35,000' at a certain engine RPM (N1) , it should have a certain exhaust gas temperature and a certain fuel flow. If by chance, one engine ingested some small stones or maybe a bird on take off which did some internal damage. This would cause the engine to have to increase the fuel flow to maintain the same RPM which would also raise the EGT. These changes would show up through the info sent on the data radio. Minor damage like this happens fairly often and what would happen is they'd inspect the internal parts of the engine (by borescope) to see how bad it was. In the case of overseas flights, they would probably use a satellite radio system to send out this type of data.

This system was reporting numerous problems with this plane. A major loss of electrical power. The engines each have an a/c. genorator, each of which is capable of supplying enough power to "fly" the plane. They were probably running on battery power when these messages were being sent out.They were also reporting loss of pressurization. Air is bled off the engines to pressurize the plane. Usually if you lose one engine, you have to go to a lower altitude, because one engine cannot keep up with the demands of flying at the higher altitude, but it sounds like this aircraft had lost both sources of air.

They also reported damage to flight controls. Each flight control such as aileron, rudder, elevator is powered by three actuators, if one jams, the other two will take over, bypassing the other ones by the way they are linked together. This will generate a computer message. Also loss of hydraulic pressure will generate a message.

Bottom line is I think and it at this point it is just a guess at this point but this wasn't caused by a malfunctioning air speed indicator which led to loss of control. It was caused by a major event. Either being hit by lightning that caused an explosion or more likely, encountering severe turbulence which tore her apart. Of course we cant rule out a terrorist act at this point.

Aircraft get hit by lightning all the time. We have numerous aircrat in our fleet that have these small series of dots along sections of the fuselage where lightning has hit. Lightning strikes are typically nothing to worry about. But there is an enormous amount of power there, so it's I think something that can't be ruled out.

The most likely cause I would think was flying into a strong storm cell that broke it up. Typically airplanes rely heavily on their weather radar for flying near thunderstorms. In fact they cannot legally fly, if there is any bad weather along their flight path if the radar isn't working. Sometimes these storm cells form quickly. There have been cases where radar images have been mis-interpreted. Who knows?

I read earlier that someone said airplanes are designed to withstand high winds. They are. Mostly horizontal winds. That's how those storm tracking planes can fly through those hurricanes. Vertical winds are a different story. The planes are well designed and very strong but this one may have met it's match. Maybe it flew into the "perfect" storm cell.

Maybe we'll find out exactly what the capabilities of the U.S. Navy are now. They'll want to pull up the black boxes for this plane, no matter how deep. They definitely want to know whay went wrong with this aircraft.

My thoughts and prayers go out to the victims and their families.