Air France 447

[rattlsnak]

W.T.F.?

Horrible news, but all I could think of when I first heard about it, was LOST...

[rick-l]

Anybody else have a bad feeling about this? 4 year old airliners don't just disappear with no contact.

[Porsche-O-Phile]

Something has to go TERRIBLY wrong for a modern commercial jetliner to simply drop out of the sky. Either a midair collision, a bomb, something.

Aircraft are hit by lightning all the time. Doubtful that would just knock one out of the sky.

[Axeman]

Terrible news, I fly back and forth to Europe all the time and always think how horrible it would be to crash in the Atlantic. Hope they find the plane and the black box to see what exactly happened.

[Porsche-O-Phile]

How long do you think before some nutball terrorist group claims responsibility (whether they actually had something to do with it or not), or before some "official" puts out a statement that some terrorist group has claimed responsibility (in order to keep the fear mongering going)?

Nobody knows who to believe anymore. Here's to hoping the FDR and CVR are recovered.

[URY914]

This sounds like a great plot for a TV show.

[flatbutt]

CNN says that the crew reported loss of electrical power and cabin pressure. So for the non-pilots like me... what exactly would that present a pilot with?

[Walter_Middie]

What is loss of cabin pressure? The plane flys at 40,000 ft or more, and the cabin is pressurized to about 6,000 ft. If you start losing cabin pressure, the pilots will begin to descend. Not a crazy dive, just a fast descent down to a better altitude. The idea is that as the cabin altitude goes up, the plane is coming down. At some point the cabin altitude becomes the outside airplane altitude - they should be down to about 25,000 ft by this point - as long as there isn't a really big hole somewhere. The descent continues until you reach about 10,000 ft. Takes about 6 minutes from cruise altitude to a safe to breath altitude. Oxygen masks are needed for the descent.

This airplane supposedly went through severe turbulence - Something sudden had to happen for them not to be able to call out a may day.

[vash]

holycrap! i used to think going down in a plane accident would be a halfway decent exit plan. but i didnt factor in the fear. all that screaming and praying...yikes.

i dont even know what to think about this one. i was always under the impression that planes were tracked 100%. i feel for the families. not knowing sucks.

[rick-l]

What would do this?

It sent an automatic message fourteen minutes later at 0214 GMT (10:14 p.m. EDT Sunday) reporting electrical failure and a loss of cabin pressure.

[MT930]

In plane with fly by wire control , meaning the control inputs to control surfaces are electronic.

Instead of cables and hydraulics, electric issues are very very big problems! controls can be lost. They have many redundancies to safe guard these unless they had a catastrophic event of some type.


Sounds like the planes control telemetry was sent to the manufacture, Airbus remotely during the problem. Location information however maybe difficult to ID.

[Heel n Toe]

Originally Posted by MT930

Instead of cables and hydraulics, electric issues are very very big problems! controls can be lost. They have many redundancies to safe guard these unless they had a catastrophic event of some type.

Yeah, very scary stuff considering they were headed into some massive thunderstorms just before things went bad.

[Porsche-O-Phile]

Electrical power loss on a modern jet is pretty much a death sentence. EVERYTHING is electronic now - instrumentation, engine controls, flight surface controls, etc. However this is extremely unlikely given how redundant the systems are (and everything is shielded, etc. - one of the reasons aircraft are so expensive).

A loss of cabin pressure from 40,000 would provide a very short TUC (time of useful consciousness) unless supplemental oxygen was used and/or an emergency descent was initiated (sounds like it was).

Flying into thunderstorms is a really easy way to die - even in a modern jet with all kinds of protections. I'm thinking these guys punched into a CB cell and it tore them up, but we'll see.

Very interesting to see what's going to come out of the investigation.

[Dantilla]

Another problem with over-water depressurization-

Jet engines gain efficiency with altitude. They are notoriously thirsty at low altitude. If they had to make a decent to 10,000 feet over open water, they would not have enough fuel to reach land.

There are a few corporate jets based at my local airport. They try to coordinate with the tower that once they begin to taxi, they are able to continue directly onto the runway, and take off without stopping. Sitting on the taxiway, an idling jet engine is using similar fuel flow as high-altitude cruise speed.

When on the ground in my little airplane, I always let the jets go first. If I tell the tower guys that I will hold for the jet, the jet's crew always says thanks.

[Jim727]

This is the time to wait for a good accident investigation. Lots of things can go wrong; what brought it down remains to be seen.

T-storms can be really vicious - pilots usually go to great lengths to stay out of them. It will be interesting to learn how severe these were and why they weren't or couldn't be avoided.

Lightning striking composite surfaces can be more of a problem than lightning striking metal surfaces. Composites need associated conductive surfaces to route lightning energy away.

Electrical failure is a matter of degree. I don't know how the A-330 controls cabin pressure, but losing electricals and cabin pressure together might suggest a combination of problems. There is also the question of whether the lightning strike affected the fly-by-wire systems.

Severe accidents usually have more than one cause, and this one might take a while to get answers.

[Joeaksa]

I always carry a hand held GPS when on overwater flights. You cannot depend on the ships electronics to get you home, and I WILL make it home.

That said, Airbus puts everything in electronics and everything depends on computers and so on. Boeing does not and lets the pilots be more of a controlling agent than Airbus. There are systems on the Airbus that can actually over-rule the pilots and frankly this is pure BS in my silly mind. We can see the situation and think about it, but thats not what they want.

"If it aint Boeing, then I aint going!"

Joe A

PS no one seems to have remembered the ELT. This communicates with satellites ANYWHERE in the world and its powered by itself, not ships power. Why didnt it signal something? Wonder if the airplane is sitting on its belly on a beach on the Western coast of Morocco?

[Heel n Toe]

Originally Posted by Joeaksa

PS no one seems to have remembered the ELT. This communicates with satellites ANYWHERE in the world and its powered by itself, not ships power. Why didnt it signal something?

Not sure what ELT is, but one cable news report I saw said there was an "automated transmission" of some sort just as they lost contact with the plane.

[Heel n Toe]

The flight left Rio on Sunday at 7 p.m. local time. About four hours later, the plane sent an automatic signal indicating electrical problems while going through strong turbulence, Air France said.

:::::::::::::::::

"It's going to take a long time to carry out this search," Douglas Ferreira Machado, head of investigation and accident prevention for Brazil's Civil Aeronautics Agency, or ANAC, told Globo news. "It could be a long, sad story. The black box will be at the bottom of the sea."

Air France-KLM CEO Pierre-Henri Gourgeon, at a news conference in Paris, said the pilot had 11,000 hours of flying experience, including 1,700 hours flying this aircraft. No name was released.

Aviation experts said it was clear the plane was not in the air any longer, due to the amount of fuel it would have been carrying.

"The conclusion to be drawn is that something catastrophic happened on board that has caused this airplane to ditch in a controlled or an uncontrolled fashion," Jane's Aviation analyst Chris Yates told The Associated Press.

"I would suggest that potentially it went down very quickly and so quickly that the pilot on board didn't have a chance to make that emergency call," Yates said, adding that the possibilities ranged from mechanical failure to terrorism.

Airbus declined to comment until more details emerge.


More here:

http://www.foxnews.com/story/0,2933,523701,00.html

[techweenie]

This plane (and many others, I suspect) has an electricity-generating turbine that can be lowered into the airstream to provide emergency power. AFAIK, the Airbus 330 is a fly-by-wire aircraft, and would have this backup system in case of catastrophic electrical failure.

Speculation at this point isn't all that useful, though. Hard to imagine what one's last moments would be like, falling toward the ocean.

[slodave]

Quote de Joeaksa

PS no one seems to have remembered the ELT. This communicates with satellites ANYWHERE in the world and its powered by itself, not ships power. Why didnt it signal something?

Not sure what ELT is, but one cable news report I saw said there was an "automated transmission" of some sort just as they lost contact with the plane.

ELT - emergency locator transmitter.