So back to the question, what was the debris from?

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In summary: I can at least see them or have pictures of them.In summary, conflicting reports are being made about why Air France jet crashed with 228 aboard. It is unclear if the debris found earlier is from the missing plane, but the air force has said that it is not. Two Spanish pilots say they saw "intense flash" in the area where the jet crashed, and Brazilian minister says that oil slick is ruling out a midair fire or explosion as the cause of the crash.
  • #71
Just out of curiosity, this flight disappeared from radar. Why aren't aircraft tracked by GPS? Is there no permanent contact/tracking with an aircraft?

Jared
 
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  • #72
GPS is one-way/passive. The receivers don't communicate with the satellites. And I don't think the plane near enough to land to be on radar - it was transmitting its position via some radio based communication network. That's why it was so easy to find the crash site.
 
  • #73
Surely there are better tracking systems? I somehow find you saying it was easy to find the crash site a bit unbelievable. Took them a fair bit of time, plus they didnt confirm the debris straight away (hence this thread).
 
  • #74
jarednjames said:
Surely there are better tracking systems? I somehow find you saying it was easy to find the crash site a bit unbelievable. Took them a fair bit of time, plus they didnt confirm the debris straight away (hence this thread).

For a long time, there's been emergency beacons that transmit a signal to some NOAA satellites (http://searchandrescue.gsfc.nasa.gov/dass/cospas_sarsat.html ). There's some limitations inherent in the current system - high rate of false alarms, hours to pinpoint the location, etc.

The follow-on system, http://searchandrescue.gsfc.nasa.gov/dass/index.html , should be much more effective and compatible with the emergency beacons already used with SARSAT. The primary advantage is that this will be a secondary payload on GPS satellites and there will almost always be at least 4 GPS satellites in view.

NASA Search and Rescue overview
 
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  • #76
Moonbear said:
I wasn't expecting them to get food and water into the raft, which is why I suggest time has run out even if there were initially survivors. What would they have as food? Maybe if they were REALLY lucky, they'd have the airplane peanuts from the galley, but planes only carry enough food for one meal, two tops, and I'd expect even if some were salvaged, most would have gotten away during a crash.

There were two links posted about people who survived for extended (months) lengths of time on rainwater and fish
 
  • #77
Some of the wreckage has been found and so have several more bodies.

The Brazilian Air Force has found 15 bodies floating in the ocean near where investigators believe doomed Air France Flight 447 crashed.

They also discovered further debris from the plane yesterday, including a section of fuselage bearing the Air France logo.

http://www.dailymail.co.uk/news/wor...t-447-disappeared-bodies-recovered-ocean.html

http://news.yahoo.com/s/ap/20090608/ap_on_re_la_am_ca/brazil_plane
 
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  • #78
BobG said:
A person would be better off drinking their own urine than drinking seawater.

Seawater is about 4% salt. Salt concentration of urine varies a lot, but would be about 2% max. If the person was well hydrated before being stranded, the first couple cycles of urine would probably be well below that, but, since the person is just reingesting waste, the concentration would quickly build up.

The person might gain an extra day or so if he's stranded for a short time - at least he's maximumizing the concentration of the little liquid he does have to expel.

If more than a very few days, he's not prolonging anything - he's not getting rid of toxic wastes from his body. The only advantage over seawater is that at least the person wouldn't be adding salts from external sources.

What are the odds that anyone surviving an airplane crash into the middle of the ocean still had a full bladder as they were climbing into life rafts?

Office_Shredder said:
There were two links posted about people who survived for extended (months) lengths of time on rainwater and fish
They started out with fresh water supplies and some food in each of those cases, and had the means to catch fish. When you are in a life raft full of passengers from a crashed flight, you don't start out with supplies. This isn't even the sort of life raft that a fishing vessel would have with a canopy and flares. As far as I know, on a commercial flight, it's the inflatable slide used for exiting the doors that can be detached for use as a life raft.

Crashing during a storm, I'm not even sure people would have managed to stay in such a raft as it was tossed in the waves.
 
  • #79
jarednjames said:
Surely there are better tracking systems? I somehow find you saying it was easy to find the crash site a bit unbelievable. Took them a fair bit of time, plus they didnt confirm the debris straight away (hence this thread).
They found several debris fields within a day or two and I'm assuming one was the right one. It took several days to confirm only because it took ships a while to get on site and the weather was bad.
 
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  • #80
Moonbear said:
This isn't even the sort of life raft that a fishing vessel would have with a canopy and flares.
I'm not sure that's true. These things are huge and weigh a good hundred pounds - I'd be surprised if they don't throw in 10lb of key provisions/equipment like a flare gun, mirror, fishing pole, and hand-crank RO machine.
 
  • #81
russ_watters said:
I'm not sure that's true. These things are huge and weigh a good hundred pounds - I'd be surprised if they don't throw in 10lb of key provisions/equipment like a flare gun, mirror, fishing pole, and hand-crank RO machine.

Just a thought, but if people had certain things on them, plastic or something couldn't they construct something to convert salt water to fresh(ish) water? An evaporator? wouldn't need to be that big but would give something. Obviously they would need some rather specific things, a carrier bag for instance.

Jared
 
  • #82
RO (reverse osmosis) machine is just that.

Edit: something like that for example: http://www.campingsurvival.com/kahaemdewama.html - these things exist and I suppose they are part of the life raft equipment.
 
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  • #83
russ_watters said:
I'm not sure that's true. These things are huge and weigh a good hundred pounds - I'd be surprised if they don't throw in 10lb of key provisions/equipment like a flare gun, mirror, fishing pole, and hand-crank RO machine.

For a commercial flight, I don't think they have much other than a flare gun, a radio, light and locator signal thing. I suspect the rest of the regulations for "extended overwater flights" apply to things like Coast Guard helicopters that are likely to be pushing their fuel supply limits, since there's no way a commercial airline has 2 days of water per occupant in one of those inflatable slides/rafts (that would be an awful lot of stuff to get out of the way if using it for a slide!)

http://www.winslowliferaft.com/fars.asp

Though I missed this story earlier this year...I don't know if this is resolved yet, or if your best bet for an empty seat next you is still American Airlines 767s. That was their solution to not having enough life rafts...leave empty seats on the plane.

http://www.nbcdfw.com/news/business/FAA-Looks-Into-American-Airlines-Life-Raft-Shortage.html
 
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  • #84
Borek said:
RO (reverse osmosis) machine is just that.

Edit: something like that for example: http://www.campingsurvival.com/kahaemdewama.html - these things exist and I suppose they are part of the life raft equipment.

I do apologise, I read it in a rush and thought it said row, as in oars or something.
 
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  • #85
Moonbear said:
What are the odds that anyone surviving an airplane crash into the middle of the ocean still had a full bladder as they were climbing into life rafts?

Just another thing to think about as you're plunging towards the ocean. Those that have exercised forethought and self-control just get a lot luckier than the others.

I, for one, am not sharing.

Well, unless one of the other survivors is really hot looking, of course.
 
  • #86
Eight more bodies also were found, bringing the total recovered to 24 since Air France Flight 447 disappeared with 228 people on board, according to Air Force Col. Henry Munhoz.
http://news.yahoo.com/s/ap/20090608/ap_on_re_la_am_ca/brazil_plane
 
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  • #87
Autopsies suggest Air France jet broke up in sky
http://news.yahoo.com/s/ap/20090617/ap_on_re_la_am_ca/brazil_plane
SAO PAULO – Autopsies revealed fractures in the legs, hips and arms of Air France disaster victims, a Brazilian official said Wednesday. Experts said those injuries — and the large pieces of wreckage pulled from the Atlantic — strongly suggest the plane broke up in the air.

With more than 400 bits of debris recovered from the ocean's surface, the top French investigator expressed optimism about discovering what brought down Flight 447, but he also called the conditions — far from land in very deep waters — "one of the worst situations ever known in an accident investigation."

French investigators are beginning to form "an image that is progressively less fuzzy," Paul-Louis Arslanian, who runs the French air accident investigation agency BEA, told a news conference outside Paris.

"We are in a situation that is a bit more favorable than the first days," Arslanian said. "We can say there is a little less uncertainty, so there is a little more optimism. ... (but) it is premature for the time being to say what happened."

A spokesman for Brazilian medical examiners told The Associated Press that fractures were found in autopsies on an undisclosed number of the 50 bodies recovered so far. The official spoke on condition he not be named due to department rules.
. . . .
Presumably bodies when flying in numerous directions and hitting the water at terminal speed would be fatal. Most people would likely have been unconscious once the pressure dropped - at about 34,000 ft (~10 km) the pressure is about 0.24 atm / 3.47psia / 23.93 kPa.

http://www.engineeringtoolbox.com/air-altitude-pressure-d_462.html

And the air is rather cold: -52.4°C / -62.2°F
http://www.boeing-727.com/Data/fly odds/standard alt.html

And the plane was probably doing about 500 mph.
 
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  • #88
  • #89
I was talking with someone who mentioned that they (Airbus) didn't know until recently that they had all this data from the Airplane because each Airbus Aircraft has a satellite link that sends information about the airplanes status during the flight so that if it needs repairs they have the parts ready by the time the airplane lands. This reduces downtime and generates more money for the airline companies. Welcome to the future.
 
  • #90
Cyrus said:
I was talking with someone who mentioned that they (Airbus) didn't know until recently that they had all this data from the Airplane because each Airbus Aircraft has a satellite link that sends information about the airplanes status during the flight so that if it needs repairs they have the parts ready by the time the airplane lands.

Do you mean Airbus didn't know what they put on their planes? Like "OMG, I have just learned - after over forty years - that my left hand have five fingers"?

From the very beginning we were all the time told about 24 (or something) failure messages sent automatically by plane. From what was repeated - ad nauseam - by media, these messages serve just the purpose you have mentioned - they help in servicing the plane once landed. I suppose s/he referred to these messages? Or is there something new?
 
  • #91
Borek said:
From the very beginning we were all the time told about 24 (or something) failure messages sent automatically by plane. From what was repeated - ad nauseam - by media, these messages serve just the purpose you have mentioned - they help in servicing the plane once landed. I suppose s/he referred to these messages? Or is there something new?

Airbus obviously know they fit an ACARS, but how much data they configure it to send and if they log and/or store the messages is upto the individual airline or sometimes the maintenance contractor. So the airframe maker cannot rely on the messages for accident investigation.
Rolls-Royce particularly log a huge amount of data for their engines which the airframe maker and the airline wouldn't know about and wouldn't normally have access to.

The ACARs is also used by the airline to generate ontime departure/arrival info which has led to allegations of some flight crews (not AirFrance!) being a little naughty by opening the door while still taxiing (so the ACARS logs an earlier arrival time for a late flight) or pulling fuses if they are over hours.
 

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