Air France 447 - On topic only!

[Myndee]

Spirit Airlines.

Save your breath Peter. The Scarebus cult is deaf to reason.

That, good sir, is false.

[Black Ram]

So what materials about the Bus did they give you to study?
Why do you have a pic of the pretty Steelers A319, if you dislike/fear the Bus?
Sounds like these things are becoming popular in the US.

[MCM]

Myndee,

I personally disagree with a couple of the airbus philosophies, but that is my personal opinion.

What isn't opinion, however, is accident statistics.

For example, compare aircraft.

A320 vs 737 accident rates for the modern aircarft. How many 737-800's crash compared to A320's for similar operators?

How about A330's vs 767's?

I think you'll find the stats will reveal that in terms of global aviation safety, the Airbus certainly holds its own - but perhaps for different reasons than the Boeing.

General:
The ice crystals Evan talks about in scenario A are an interesting phenomenon that is being looked at more and more. Engine failures due to ice outside the normal icing range (below -40 SAT... too cold for ice) have cropped up a fair bit over the last few years, and we are learning more and more about them. Conversely, the rapid increase in SAT (such as scenario B) can quickly put the aircraft above its maximum thrust limited altitude and have speed quickly reducing.

It will certainly be interesting to see what is on the FDR.

[Theoddkiwi]

It's the first time I am posting on this thread, so
Now, the most plausible to point out (I was also a bit skeptical about it at the beginning, myself), is that, in such a convective thunderstorm cell, especially in the ITCZ, thunderstorms regularly imply vaste releases of energy, in the form of thunder and electrical discharge! Now it is not uncommon, for such thunderstorms or thunderstorm system (which is the case here), to produce ball lightning, which, is known to have a particular attraction to metals, an have a reasonably higher voltage than regular bolt lightning. It is also known to have entered into flying airplanes! Now correct me if I'm wrong, but a ball lightning strike (or, call it what you want), could reak havoc into a plane's sitems, in less than a second. It could fry the radio comms, screw up the flight computers (so vital to an Airbus, as we all know), allowing the PIC very few seconds to react, and also cause all the errors in the flight systems, seen on the ACARS messages.

I know this was a while back, but anyway.
Our fleet get hit by lightening often due to climate that we fly in. Aircraft are well capable of withstanding most lightening strikes. The belief that all the avionics will explode and the aircraft fall apart is crap.

Electricity will always take the path of least resistance, everything on the aircraft is bonded to the airframe with metal braid straps. What these straps do is ensure that electrical charge from one part of the aircraft can pass easily through the metal structure and skin and out to the static dischargers then out to the atmosphere. The path of least resistance.

What electrical charge won't do is work down into the airframe and into the electronics boxes which are themselves metal boxes which are also bonded to the airframe.
Even if a lighting strike charge did try to pass though the avionic bays it will pass around the metal boxes and not through the electronic cards inside as they pose higher electrical resistance.

Lightening Strikes will almost always cause some surface damage to the external aircraft structure, typically burnt rivet heads and some damage to the skin where it entered and exited.

It will sometimes cause damage to some structural and composite components and this is often due to less than perfect bonding.

It will occasionally damage susceptible radio systems typically the HF radio system being most common due the big antenna. But very rarely if ever all communications as each system is independent and often duplicated so the same fault occurring to multiple systems is almost impossible.

It can very very rarely cause disruption to the Navigation, Flight control and Engine Control systems. But almost never all at the same time.

Sorry but aircraft are just to well designed to be at any real risk to lightening.

Lightening Strikes are the most overrated hypothetical cause of aviation accidents and most frequently blamed by the media and witnesses.
The fact is that there have only been a handful of accidents where a lightening strike led to the loss of an aircraft. I believe the last commercial airliner was a Pan Am 707 in 1968 when fuel vapor ignited and the aircraft exploded.

Lightening did not cause AF447 to crash nor any other airliner in the last 40 years.

[Evan]

Lightening Strikes are the most overrated hypothetical cause of aviation accidents and most frequently blamed by the media and witnesses.
The fact is that there have only been a handful of accidents where a lightening strike led to the loss of an aircraft. I believe the last commercial airliner was a Pan Am 707 in 1968 when fuel vapor ignited and the aircraft exploded.

I've even read somewhere that that Pan Am 707 was possibly hit by positive lightning, which is far more powerful than conventional lightning. I've also read that aircraft are not (cannot be?) designed to survive positive lightning strikes. But positive lightning is extremely rare and I'm not sure if it can occur over deep water anyway, since it originates from the earth. I'm NOT suggesting this as a theory for AF447.

Question though: If conventional lightning strikes near the nose of a plane, what effect could it have on the pitots or pitot transponder units, or the associated wiring (the A330 being a pitot-by-wire aircraft)?

[Jpmkam]

First Body Recovered From Air France Crash Debris On Seabed

Nearly two years after Air France Flight 447 mysteriously crashed into the Atlantic Ocean off Brazil, crews are raising the first victim's body from the ocean floor. The debris is about two and a half miles below the water's surface and crews have located some wreckage, including the two critical flight data recorders that might indicate what caused the plane to go down in a violent thunderstorm.

CNN says the victim's body is skeletal and still strapped to an airplane seat. Eleanor Beardsley told NPR's All Things Considered last month not all relatives of the victims want the bodies raised to the surface. Fifty-one bodies were recovered after the accident and Eleanor says another 50 bodies were discovered by underwater cameras.

[TeeVee]

Myndee,

I personally disagree with a couple of the airbus philosophies, but that is my personal opinion.

What isn't opinion, however, is accident statistics.

For example, compare aircraft.

A320 vs 737 accident rates for the modern aircarft. How many 737-800's crash compared to A320's for similar operators?

How about A330's vs 767's?

I think you'll find the stats will reveal that in terms of global aviation safety, the Airbus certainly holds its own - but perhaps for different reasons than the Boeing.

I agree with you MCM, and apparently, so does Boeing. check out their own data regarding accident rates.

www.boeing.com/news/techissues/pdf/statsum.pdf

even given that, i think if you do a more detailed analysis, taking into consideration the number of years the model has been in service, the number of flights etc etc, the stats MAY look a bit different.

ad.com used to maintain a database with what appears to be more data but it only runs through 2004.

[TeeVee]

First Body Recovered From Air France Crash Debris On Seabed

we are truly sick to exhume skeletal remains. this should be their final resting place. yeah yeah to each their own, but how selfish and self-centered is it to disturb the remains for no good reason? i would bet a princely sum that the skeletal remains will not reveal anything pertinent about the crash. and as for the parts of the aircraft the bodies are attached to, if the fdr and cvr do not reveal the cause does anyone here really believe a pax seat will??

my .5 cent

[Joe H]

I've even read somewhere that that Pan Am 707 was possibly hit by positive lightning, which is far more powerful than conventional lightning. I've also read that aircraft are not (cannot be?) designed to survive positive lightning strikes. But positive lightning is extremely rare and I'm not sure if it can occur over deep water anyway, since it originates from the earth. I'm NOT suggesting this as a theory for AF447.

Question though: If conventional lightning strikes near the nose of a plane, what effect could it have on the pitots or pitot transponder units, or the associated wiring (the A330 being a pitot-by-wire aircraft)?

Hi Evan, interesting stuff, however I would add that positive lightening as such originates at cloud level, not the earth, most lightening originates at the earth. the postive (theoretical) strikes originate above and meet already originated strikes. I am not dismissing your hyposthesis, I would just add that the fdr does not seem to support this, or should I say acars info... Lansa 508 is another great example.. but both that and the 707 incident resulted in fuel combustion afaik. no evidence has been found of combustive processes on AF447, but.. who know ?
I doubt the sequence of interument reporting would follow that theory.. but, again, we are hopefully a few weeks away from first transcripts, so who knows ? Damage to electrical instrumentation seems to be highly unlikely.. often one only knows the effect after the cause.

[Joe H]

we are truly sick to exhume skeletal remains. this should be their final resting place. yeah yeah to each their own, but how selfish and self-centered is it to disturb the remains for no good reason? i would bet a princely sum that the skeletal remains will not reveal anything pertinent about the crash. and as for the parts of the aircraft the bodies are attached to, if the fdr and cvr do not reveal the cause does anyone here really believe a pax seat will??

my .5 cent

Who is the 'we' ? surely some want closure, some dont.
I find, in light of recent events, your post to be quite controversial. How selfish and self centered is it for some country to bury a politcal assisination at sea. With no respect for family or relatives. ? Beggars belief... Sorry, but...

[Fear_of_Flying]

we are truly sick to exhume skeletal remains. this should be their final resting place. yeah yeah to each their own, but how selfish and self-centered is it to disturb the remains for no good reason? i would bet a princely sum that the skeletal remains will not reveal anything pertinent about the crash. and as for the parts of the aircraft the bodies are attached to, if the fdr and cvr do not reveal the cause does anyone here really believe a pax seat will??

my .5 cent

I don't think a body will reveal much if the FDR and CVR do not. However, if investigators put together a framework for what happened, this evidence could further corroborate such an explanation. Scientists seem to like corroborating evidence. And as you say, some people would like the remains undisturbed, but others would like them returned home. Whichever the case may be, they are but empty shells, on that most would probably agree, and could probably deal with it either way. I think I would want a loved one left at sea, but I can't even be certain of that - until you're in the situation, how can you be?

[Fear_of_Flying]

I've even read somewhere that that Pan Am 707 was possibly hit by positive lightning, which is far more powerful than conventional lightning. I've also read that aircraft are not (cannot be?) designed to survive positive lightning strikes. But positive lightning is extremely rare and I'm not sure if it can occur over deep water anyway, since it originates from the earth. I'm NOT suggesting this as a theory for AF447.

Question though: If conventional lightning strikes near the nose of a plane, what effect could it have on the pitots or pitot transponder units, or the associated wiring (the A330 being a pitot-by-wire aircraft)?

That last bit is an interesting idea I don't think we discussed - what if it wasn't the pitot tubes themselves that were faulty, but the wiring? Would that scenario produce the same effect as what the ACARS showed? We better figure this out fast, we'll soon have the real answers.

[Evan]

Hi Evan, interesting stuff, however I would add that positive lightening as such originates at cloud level, not the earth, most lightening originates at the earth. the postive (theoretical) strikes originate above and meet already originated strikes.

Yeah, I guess I got that backwards. It's been a while since I read about it. One thing I remember is that positive lightning can travel laterally before striking down and strike many miles distant from a convective storm. Frightening. Anyway, as I said, I don't think lightning was at fault with AF447 unless it had some destructive effect on the pitot system. I still find the ice crystal or supercooled water theories most plausible.

[Evan]

What isn't opinion, however, is accident statistics.

For example, compare aircraft.

A320 vs 737 accident rates for the modern aircarft. How many 737-800's crash compared to A320's for similar operators?

How about A330's vs 767's?

I think you'll find the stats will reveal that in terms of global aviation safety, the Airbus certainly holds its own - but perhaps for different reasons than the Boeing.

Of course, these raw statistics are misleading. In comparing the relative safety of the aircraft design, you have to deduct any crashes that were not due to design or mechanical issues, and only then are these stats useful. For instance, the 767 has had a number of hull loss incidents, but only one crash I am aware of related to mechanical issues, and this was an early ER model with a flawed reverser design which has since been replaced fleetwide. Other crashes were due to 'foul play' and pilot error (not stall-related). These could have involved any airframe. Therefore, despite the raw statistics, I consider the B767 to be among the safest aircraft ever designed.

[guamainiac]

Under the terms stated then every sniper since perhaps 1776 should be unearthed and shot for a war crime?

Back to AF however. The way the AC crushed and the metal sheared a microscope will certainly tell a tale about which components were going in what direction.

However (nasty little word), if ... if, there was a chance that the fracture pattern on the remains or tissue analysis (cold does preserve as does salt), then bring some up for examination.

TeeVee, the big question for you is how can you possibly recover component parts without the remains coming along.

I mean, at that point regarding the remaining kin, you have to almost make a decision to .... or get off the proverbial pot. I would not go to extraordinary means to obtain remains.

For that matter when you look at what I consider to be almost insane and I mean no disrespect to anyone, I think the degree of recovery from the WTC rubble that was carted off was crazy. But, that said I am within 50 miles and there was involvement, but it was driven by the Rabbis who stated that every body part had to be recovered. This process took years and just wrapped up a short time ago.