Air France jet with 228 people aboard missing

[ShibbOleth]

@ShibbOleth

The “current event” article lists the flights captain as Robert Piché. Not sure if this is correct, or if it’s the same guy, but there is a Captain Robert Piché who is famous for saving another flight.

Wikipedia no longer lists a name for the Captain of Air France flight 447.

[Richard_Pearse]

@Waffle_Decider

Planes do sort of have radio contact with the ground over the ocean. This is done through HF radio, instead of the VHF radio normally used over land. HF radio can sometimes be very flaky, however, and is a PITA in general.

Yeah, HF can be a nightmare to use. Sometimes it’ll be clear as VHF then 30 minutes later all you can hear is static and chatter in foreign languages. Or you can hear ATC clearly but they can’t hear you, or vice versa.

On the other hand, all the airliners normally have one radio monitoring 121.5 so a distress call on that frequency will normally be heard by someone, somewhere.

Distress calls, though, are generally something broadcast if you have the time to do it. You might not send a distress call because you don’t have a functional radio, you think you have it under control, or you are desperately trying to get it under control and don’t have time.

[Broomstick]

@UncleRojelio

Do the life rafts in transport aircraft contain EPIRBs? How many EPIRBs would be aboard an transport aircraft?

Maybe I just don’t have enough caffeine in me yet this morning, but what’s an “EPIRB”?

[Richard_Pearse]

An EPIRB is like an ELT. Wiki.

[Shirley_Ujest]

If there is any comfort in this disaster, at least the rescue & recovery will be happening in Spring/Summer weather.

[Broomstick]

Um… somehow I thought that this occurred in the southern hemisphere, in which case we’re talking fall weather.

[Magiver]

Brazilian A/F reporting wreckage 400 miles out (oil, seat cushions). So now they have a zone to search.

[ShibbOleth]

@Broomstick

Um… somehow I thought that this occurred in the southern hemisphere, in which case we’re talking fall weather.

It’s in or near the tropics, but it is in the southern hemisphere.

[Kalhoun]

@Broomstick

Um… somehow I thought that this occurred in the southern hemisphere, in which case we’re talking fall weather.

My co-worker is in Brazil and she said they were at 0 degrees C this morning. It’s definitely not warm there.

[ShibbOleth]

Which part of Brazil? It’s a big country. That’s sort of like talking to your co-worker in the USA and finding out the temperature. My understanding is that they went down northeast of Recife and Yahoo weather shows the temps there in the low 80s F.

[jjimm]

Ocean Debris Spotted.

[jjimm]

Riverdance dancer (presumed) killed.

[Kalhoun]

@ShibbOleth

Which part of Brazil? It’s a big country. That’s sort of like talking to your co-worker in the USA and finding out the temperature. My understanding is that they went down northeast of Recife and Yahoo weather shows the temps there in the low 80s F.

She’s in the lower quarter of the country in Sao Paulo. I was under the impression the search zone was more due west-northwest rather than as far north as they are saying.

[JRDelirious]

@Broomstick

Um… somehow I thought that this occurred in the southern hemisphere, in which case we’re talking fall weather.

But the actual location of the crash is near equatorial so fall/spring is moot. Much of the area is currently in a more or less ongoing “summer thunderstorms” condition.

[Richard_Pearse]

Yeah it’s always relatively warm. The weather is largely defined by the location of the ITCZ or equatorial trough which is where most of the thunderstorms occur.

[Northern_Piper]

one suggestion as to the cause is a computer glitch, as outlined in this article: A Past Flight May Offer Clues to Air France 447.

There was an episode with an Airbus over Australia where the computer put the plane into a dive:

Following an investigation of the A330’s uncommanded dive, Australian aviation officials, assisted by U.S. and French authorities, blamed a pair of simultaneous failures for the near disaster. The plane has three air data inertial reference units (ADIRUs), which are designed to help the plane’s flight-control computer fly the plane safely. The system is intended to eliminate the possibility of electronic error: the flight computer, which is always monitoring the trio, can disregard one ADIRU if it begins relaying information that conflicts with the other two.

But that’s not what happened when one of them went awry on Oct. 7 and began sending erroneous data spikes on the plane’s angle of attack (AOA) — the angle between its wings and the air flowing over them — to the flight-control computer. “For some reason, the damn computer disregarded the healthy channels,” says Hans Weber, an aviation expert who heads Tecop International, an aviation-consulting firm in San Diego. “Instead, it acted upon the information from the rogue channel.” The computer, responding to the faulty data, put the plane into a dive.

…

It is not yet known whether Air France 447, an A330, carried the troublesome variety of ADIRU. But if it did, and if the Air France plane plummeted into an uncommanded dive while traveling through a downdraft generated by storms — a common occurrence over the region of the Atlantic Ocean where the plane went down — it could have been doomed as it entered a steep dive and likely broke up.

[Xema]

@Northern_Piper

There was an episode with an Airbus over Australia where the computer put the plane into a dive…

The general subject of the vulnerability of fly-by-wire aircraft seems relevant here. Despite some of what’s being implied by some “experts”, aircraft - including avionics - can be (and have been) affected by lightning. It’s at least plausible that this could have been the case for AF 447.

Let’s hope the flight data recorder is found.

[Av8trix]

Here’s an interesting analysis of the weather present in the area at the time of the accident, including an extrapolated position overlay.
http://www.weathergraphics.com/tim/af447/

The forces that weather can exert on an airplane are extraordinary, and each storm is different from the last.