Greek F-16s intercept Helios Airways B737 [preliminary report]

F-16.net ^ | 8/14/2005 | Staff

[dr_who_2]

Why hasn't anyone in the airline industry or in the airline regulation business suggested remotely-controlling civilian airliners? If the Soviets could fly Buran by wire, why can't others do it? Yes, it would introduce another security risk, but that sort of problem has already been solved. There was some research done into making aircraft fuel less explosive in the event of a crash, but that also got sidelined.

[dr_who_2]

True, but it seems to me that the easiest way to decompress an airplane is to blow open a hole on one side of it.

[TWhiteBear]

Agreed. The facts and observations/data, at this point, do not seem to be clarifying the incident.

[HangnJudge]

True, but it seems to me that the easiest way to decompress an airplane is to blow open a hole on one side of it.

One would think the F-16's would have seen a hole
Those pilots usually have great eyes and observational skills

[Robe]

OK.. here's the poop !!!! (I'll try to keep it simple for the non tech types , so my explanation my not be EXACTLY techinacaly correct..)

The A/C and Cabin pressuration systems are interconnected In the engine( compressor section) the are a number of pick ups called p1, p2 etc,since the compressor is made in stages(each compressor turbine ring)the P1 stage would be the pick up from the 1st or the lowest/coldest section. As you go back , the compressed air gets hotter. it then passes into the ignition chamber of the engine.

Theses are called engine BLEEDS, one (I know there's more that one) feeds two AIR CONDITIONING PACKS

APU or engine P5 and if necessary P9 stage bleed air (hot) is pre-cooled by fan air before entering the pack. Inside the pack, bleed air is cooled by ram air through heat exchangers and an air cycle machine. A water separator collects water condensed by the cooling process to avoid icing.

Cabin Pressuration Panel B-373

In flight: If one pack fails with the pack switches in AUTO, the other will regulate to high flow (unless flaps are down).

If you dispatch with one pack inoperative, then max altitude is FL250. If a pack fails when above this level, then you may continue at the higher level.

This photo shows the location of the two air conditioning packs underneath the aircraft. Notice that the two ram air inlets have their deflector doors retracted because the aircraft is in-flight (see logic table below). The packs are accessed through the two large access panels between the deflector doors and the wheel well, these panels are hinged inboard. Aft of the access panels are the ram air exit louvres which give you a nice warm blast on your legs when you are stood in the wheel well doing a walk-around on a cold winter day!

As you can see the air (pressure) comming from the engines is never introduced in to the cabbin, it just heats the PACKS and is dumped overboard. So you can't have any outside "BAD AIR" in the cabin !

When the pilot is out of the cockpit it is required that the Co-pilot don the oxegin mask If a loss of pressuration was to occur at least one of the crew would be fuctioning As soon as the bells and whistles go off in a DECOM, the first thing done is the crew dons thier masks retards the powerlevers and desends.!

I find it very hard to belive that a simple LOSS of pressuration caused this Crash

Here are the Schematice of the A/C system

My 2 Cents!

Robe

[HangnJudge]

My 2 Cents!

Darn impressive, what do you come with for 2 bits?

[Robe]

I just pushed a few airplanes around for a few years, from Cubs, to F-4s to DC-3s on up to B-747s before the feds grounded me because I had turned the magic age of 60 !!

Hurrmph !!!

[Rome2000]

Terrorism seems the only likely explanation, much more plausible than decompression.

[COEXERJ145]

Terrorism seems the only likely explanation, much more plausible than decompression.

You obviously don't know much about airplanes. This is going to turn out to be an accident, not terrorism.

[dr_who_2]

Whoops. Good point.

[McGavin999]

Was Benin Sevan on the plane?

[Robe]

I agree....

I'm damned skeptical about the text message guy......

I don't want to unduly worry folks, but those masks in the back tend to leak a lot. They're made out of hard plastic and don't seal on the face well, not like the crew masks which are made of soft rubber..

IMHO the chances of this guy out lasting the crew are one in a billion.

I'm leaning toward some type of gas released into the cabin.. odorless/tasteless.. maybe introduced while in the rest room while donning a gas mask

[festus]

Since Greece has no mountains over 10,000 feet,

I checked that out and you are right. The highest point is Mt. Olympus which is 2917 meters and if I did my math right thats 9521 feet.

Since decompression would not be a problem at or below 10,000 feet what happened ?

[longtermmemmory]

don't forget the SMS message was sent in greek.

[longtermmemmory]

everyone gets knocked out at altitude and then the autopilot takes the plane dutifully down to the landing altitude. At 10,000 feet people start to regain conciousness.

[festus]

Is the autopilot that smart upon decompression to drop the altitude ?

I guess it could be and then the whole thing makes sense.

[longtermmemmory]

not to do it automatically, just to do it as a matter of course. I bet SOME people got the masks on, and they were "good enough" to keep them alive until the plane's computer ran though its flight program.

IOW the autopilot did what it was told to do.

[festus]

Maybe its just you have a better longtermmemory ?

;-)

[NY Attitude]

I just read on Fox that the airplane was intercepted at 34,000 feet. The pilot of the F-16 stated that oxygen masks inside the cabin were deployed and that the pilot of the airliner was slumped over. The F-16 pilot further stated that he saw 2 people moving about inside. At 34,000 feet there isn't sufficient oxygen to sustain life for a long period of time.

[PeoplesRepublicOfWashington]

Isn't one of the pilots always required to be on oxyen when above 12,000 feet? I don't see how decompression could have done this.