aaden
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TWA800 Fuel Tank Question

Tue Jun 02, 2009 7:22 am

I was reading a report on TWA800; am I correct that the fuel tank exploded because of a live wire? The explosion was caused by the lack of fuel in the tanks.

I don't understand why there wouldn't be any fuel in the tanks if it was crossing the atlantic.

Can anybody sum up what happened?

I'm not looking for a conspiracy, I just want the technical stuff.
 
propilot83
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RE: TWA800 Fuel Tank Question

Tue Jun 02, 2009 7:58 am

TWA-800 was a Boeing 747-200. After watching a documentary on the accident, I learned that fuel vapors were in the center fuel tank and that an air conditioning unit pack was located directly underneath the center fuel tank. Investigators had concluded that after the plane sat on the tarmac at JFK before departure, the weather was very hot that July day, and the air conditioning packs were running full blast to cool the interior of the plane, and so in doing this, the air conditioning unit underneath the center fuel tank became very hot, and after take-off, some kind of electrical wire running through the empty center fuel tank caused a spark and the fuel vapors ignited causing a massive explosion from the center fuel tank and causing the plane to break apart. The Air conditioning unit might have had something to do with the explosion and the wiring of the center fuel tank. As far as fuel not being loaded in the center fuel tank on that TWA-800 flying across the Atlantic, well perhaps the flight was only about 3,500 miles or so, and the Boeing 747-200 can fly quite a distance without the need of having fuel in the center fuel tank, I believe that the center fuel tank is used for long haul flights that are near 5,000 miles + or for emergency reserve fuel. I am not sure yet if the NTSB did eventually find the "electrical wire" that caused the spark in the center fuel tank.
 
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SEPilot
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RE: TWA800 Fuel Tank Question

Tue Jun 02, 2009 10:16 am

I knew an ex-PA 747 pilot when this happened (he was our local flight instructor); he said that the standard procedure would be to have a small amount of fuel in the center tank and you would use that on takeoff; at just about the time the plane exploded you would switch tanks. He was convinced there was something in the tank switching mechanism that sparked and caused the explosion. The NTSB was unable to identify the precise wire or function that caused the explosion, and I remain unconvinced by the official explanation. I am also dubious of the various conspiracy theories as well. But what the eyewitness saw does not square with the official explanation.
The problem with making things foolproof is that fools are so doggone ingenious...Dan Keebler
 
fr8mech
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RE: TWA800 Fuel Tank Question

Tue Jun 02, 2009 12:07 pm



Quoting SEPilot (Reply 2):
he said that the standard procedure would be to have a small amount of fuel in the center tank and you would use that on takeoff;

Not too sure about that. Standard procedure, on just about any aircraft, is tank-to-engine on take-off and landing. You would switch to the center tank after take-off and start burning the center tank to all the engines (as I recall). When the center is empty, you burn the inboards to all the engines. When the inboard quantities matched the outboard quantities, including the reserve tank(s), you burn tank-to-engine. As I recall, the override/jett pumps in the center tank will only take the tank down to 2 or 3 thousand pounds. It's up to the scavenge pump to deal with the rest. And all it does is pump the fuel into the #2 main.

Quoting SEPilot (Reply 2):
He was convinced there was something in the tank switching mechanism that sparked and caused the explosion.

Tank switching or selection is performed by pump manipulation and use of the crossfeed valves. As I recall, on the B747-classic, none of these wires run internal to the tank. The only wires I recall seeing in the center tank, or any tank, for that matter, were FQIS (fuel quantity indication system) wiring.
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dispatchguy
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RE: TWA800 Fuel Tank Question

Tue Jun 02, 2009 12:09 pm



Quoting AAden (Thread starter):
I don't understand why there wouldn't be any fuel in the tanks if it was crossing the atlantic.

The B747-100, for the relatively short flight to CDG from JFK, wouldnt need enough fuel onboard to require the center fuel tank to be loaded.

Every airliner has specific fuel loading and distributions. So if the fuel is X, we already know how that X will be divided up into the various fuel tanks on the aircraft. And, for the fuel load required on TWA800, the dispatch fuel didnt require loading of fuel in the center tank.

The fuel load was 176.6, and the distribution for this would be:

Mains 1 & 4 - Full (24.6 each)
Mains 2 & 3 - 60.1 each
Reserve 1 & 4 - Full
CWT - Empty
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Euclid
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RE: TWA800 Fuel Tank Question

Tue Jun 02, 2009 4:05 pm



Quoting Fr8Mech (Reply 3):
The only wires I recall seeing in the center tank, or any tank, for that matter, were FQIS (fuel quantity indication system) wiring.

From what I remember from the programs I have seen about this crash, the only wires in the tank were for the fuel indicators, as quoted above. These were all low current wires that would not be able to spark due to the low current carried by them. No high current wires were routed through the tank due to the danger of sparking.

However, the wiring in this plane was found to be in a very bad state, and it is assumed that a spike through one of the high current wires elsewhere found its way to the wiring in the fuel tank, causing it to spark.

The evidence for this comes from what I believe was the last words spoken on the CVR: "Look at that crazy fuel flow indicator", suggesting that something in the wiring had gone haywire.
 
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Jetlagged
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RE: TWA800 Fuel Tank Question

Tue Jun 02, 2009 4:14 pm

As well as FQIS wiring, which is low voltage, the boost pumps, situated inside each tank, require electrical power, which is a much higher voltage. However these pumps have flame suppression systems and so were discounted as a probable cause by the NTSB. A short circuit in the FQIS wiring, leading to a high voltage, was deemed to be the most likely source of ignition.

The main point about TWA800 is that the centre wing tank was empty, apart from fumes. One recommendation made after the accident was to always refill the centre wing tank with cold fuel before each departure. This avoids the problem of highly combustible fuel vapours which only need a spark to ignite. Much harder to ignite a tank of liquid jet fuel.

[Edited 2009-06-02 09:39:23]
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Jetlagged
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RE: TWA800 Fuel Tank Question

Tue Jun 02, 2009 4:47 pm



Quoting Euclid (Reply 5):
The evidence for this comes from what I believe was the last words spoken on the CVR: "Look at that crazy fuel flow indicator", suggesting that something in the wiring had gone haywire.

Fuel flow indication is entirely seperate from tank quantity indication. The fuel flow transducer is in the engine itself, nowhere near the centre tank. As well as the engine fuel flow indicator it is also connected to the engine fuel used indicator (on the F/E panel), but this is not connected to the fuel quantity indication system either.
The glass isn't half empty, or half full, it's twice as big as it needs to be.
 
fr8mech
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RE: TWA800 Fuel Tank Question

Tue Jun 02, 2009 5:30 pm



Quoting Euclid (Reply 5):
The evidence for this comes from what I believe was the last words spoken on the CVR: "Look at that crazy fuel flow indicator", suggesting that something in the wiring had gone haywire.

The fuel flow indication system is seperate from the FQIS, and on the Classic was notoriously erroneous, though most of those issues were on the ground.

Quoting Jetlagged (Reply 6):
As well as FQIS wiring, which is low voltage, the boost pumps, situated inside each tank, require electrical power, which is a much higher voltage.

The boostpumps are in the tank, but the wiring is external. Is it possible that a boost pump can produce a spark? Yes, but unlikely due to design, so I've been led to believe.
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soon7x7
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RE: TWA800 Fuel Tank Question

Tue Jun 02, 2009 9:38 pm

The current theory on the TWA800 is speculative at best, no one knows for sure the absolutes that brought down the plane. The center wing tank is about the size of a living room, 20'x20'x7'high. The inside of the tank has many baffles or walls which by design are also the wing spars. All fuel sensors and scavange pumps are of the low voltage type. The fuel itself being a highly oil base medium, helped to preserve the integrity of the wire, sealants and the condition of the aluminum inside the tanks...(virtually no corrosion, even after thirty years).The center keel beam runs throught it as well. In the tank that night were about 50 US gallons of JetA. Even with the ambient heat resulting from the three ac packs,...the fuel must be atomized or misted before it can become explosive. 50 gallons of JetA in a 20x20x7 foot room is not volitile enough to totally desomate a 850,000lb ship. Boeing has built in all precautions for heat build up and appropriate venting as the plane was designed for all environments, including desert environments. KC-135's carry 75,000 lbs of fuel and during desert storm operations while being based in hot environments that far exceeded Long Islands that day. Someday the case will be unclassified and it will be interesting to follow up on that event. Pieces of that plane are still washing up on New York beaches as about 4 tons of airframe still remain underwater...
 
474218
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RE: TWA800 Fuel Tank Question

Tue Jun 02, 2009 10:12 pm



Quoting Fr8Mech (Reply 8):
The boostpumps are in the tank, but the wiring is external.

Many boost pumps have the wiring inside the tank. Examples in the following:

http://www.parker.com/literature/Nic...for%20Literature/Brochure_Fuel.pdf

Quoting Fr8Mech (Reply 8):
Is it possible that a boost pump can produce a spark? Yes, but unlikely due to design, so I've been led to believe.

I have seen boost pumps with holes burned in the housing which suggests alot more than sparks.
 
113312
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RE: TWA800 Fuel Tank Question

Tue Jun 02, 2009 11:08 pm

I taught systems on the B747 for years and have never accepted the official conclusion. B747s have operated for decades in hot conditions around the world with little or no fuel in the center tank without exploding. The high pressure boost pumps in all of the fuel tanks use three phase alternating current so that they can impart rotary motion without the use of commutator brushes. Thus, these type of motors are hard wired and produce no sparks. In addition, the electrical portion of these pumps are in a dry cavity and not exposed to fuel or fuel vapors.

The only electrical components actually in the fuel tank are the fuel quantity sensors. These are capacitance type transduces and are powered by low voltage and very low current. THey also should not be able to produce sparks.

Contrary to what was stated by one of the other posters, the normal fuel management for a -100 series is tank-to-engine for start, taxi, and takeoff. If fuel were in the center aux tank, it would only be used once the aircraft was established in climb. Fuel is not normally carried there unless needed by the flight plan. If a little residual was there and not required, it would most likely have just been left alone. It certainly would not have been used in that part of the climb.

No matter, opening or closing of valves should not have produced an explosion. The NTSB finding, in my opinion, was in the absence of a better explanation and expedient to close the case. They never proved the case beyond a reasonable doubt.
 
fr8mech
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RE: TWA800 Fuel Tank Question

Wed Jun 03, 2009 12:28 am



Quoting 474218 (Reply 10):
Many boost pumps have the wiring inside the tank. Examples in the following:

Right, but the B747-Classic does not and this is what we are discussing. I've worked on aircraft with boost pump wiring in the tank.

Quoting 113312 (Reply 11):
No matter, opening or closing of valves should not have produced an explosion. The NTSB finding, in my opinion, was in the absence of a better explanation and expedient to close the case. They never proved the case beyond a reasonable doubt.

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Viscount724
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RE: TWA800 Fuel Tank Question

Wed Jun 03, 2009 1:54 am



Quoting Propilot83 (Reply 1):
TWA-800 was a Boeing 747-200.

It was a 747-100 (the aircraft below), not a -200.


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TUNisia
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RE: TWA800 Fuel Tank Question

Wed Jun 03, 2009 2:23 am

I still have many doubts about the governments claims regarding TWA 800.

Stuff like this...

http://whatreallyhappened.com/RANCHO/CRASH/TWA/BASS/bassett.html

still makes me wonder...
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propilot83
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RE: TWA800 Fuel Tank Question

Wed Jun 03, 2009 7:12 am

A missile did not bring down TWA-800. If a missile had actually shot the plane down, then the NTSB would not have had the capability to re-build 90 feet of the center of the plane again. You know there are always going to be rumors, theories, and a bunch of bullsh*t when events like this occur. If a missile had actually shot the plane down, the explosion would have been so big that the debris would have been no larger than the size of a car. And you know what else, the government wouldnt have kept this a secret either, because some time back in the 1970's to 1980+'s, the U.S. Navy accidently shot down an Iranian Airbus airliner in the middle east with an F-14 Tomcat. The Navy thought that it was an Iranian enemy fighter plane it was intercepting, instead later on when it was already too late.....figured out it was a bunch of innocent Iranian's flying on an Airbus jetliner. Why didnt the government keep that a secret? People will say that TWA-800 was shot down by a missile, just for the purpose of making money. Its all about money, they will print magazines, newspapers, books, a bunch of other crap just to get their pockets full of cash on some rumor out of nowhere. It is a fact, that TWA-800 was not shot down by a missile, it was a center fuel tank explosion due to some faulty electrical wiring in or near the center fuel tank with fuel vapors, or fumes in the empty tank....PERIOD!
 
PhilSquares
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RE: TWA800 Fuel Tank Question

Wed Jun 03, 2009 7:23 am



Quoting Propilot83 (Reply 15):
It is a fact, that TWA-800 was not shot down by a missile, it was a center fuel tank explosion due to some faulty electrical wiring in or near the center fuel tank with fuel vapors, or fumes in the empty tank....PERIOD!

Could you provide the data that allows you to be the authority on this matter? I have over 7000 hours in the classic and the entire sequence of events just does not make sense. While I don't subscribe to the missile theory, I certainly don't subscribe to the center fuel tank theory either.

Aircraft don't just blow up in the sky. The theories about the residual heat from ground operations and the shorting of the electrics just makes no sense.
Fly fast, live slow
 
DH106
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RE: TWA800 Fuel Tank Question

Wed Jun 03, 2009 8:19 am



Quoting Propilot83 (Reply 15):
A missile did not bring down TWA-800. If a missile had actually shot the plane down, then the NTSB would not have had the capability to re-build 90 feet of the center of the plane again....... ..... If a missile had actually shot the plane down, the explosion would have been so big that the debris would have been no larger than the size of a car.

This is undoubtably true, and though I don't necessarily subscribe to the missile theory I agree with PhilSquires and others that the facts as stated just don't add up, and like to play devil's advocate and explore all the possibilities:-

What about a missile that didn't explode - either through failure or through a dummy warhead..This could leave the 'residue' alluded to in TUNisia's link (reply14) unburnt and if it struck the 747 in a critical area around the center fuel tank it could quite possibly set off the explosion in that tank that set in train the structural break up.
...I watched c-beams glitter in the dark near the Tanhauser Gate....
 
jwenting
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RE: TWA800 Fuel Tank Question

Wed Jun 03, 2009 11:52 am



Quoting PhilSquares (Reply 16):
Aircraft don't just blow up in the sky.

Tell that to the next of kin of the A330 that crashed monday...
Accidents happen.

TWA800 like all of them was a complex combination of unlikely events and failures that when combined in the right order and under the right environmental conditions led to catastrophe.
Had there been a bit more fuel in that tank, had the short happened at a somewhat different altitude, had the aircraft not been delayed (causing the airco unit to be hotter than normal at that stage during the flight), etc. etc.etc., it would likely not have crashed.
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PhilSquares
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RE: TWA800 Fuel Tank Question

Wed Jun 03, 2009 12:24 pm



Quoting Jwenting (Reply 18):
Tell that to the next of kin of the A330 that crashed monday...
Accidents happen.

So, you have the AF crash all figured out! Amazing!!! Perhaps you need to re-read my post. I never did say accidents don't happen, what I did say was aircraft just don't explode in flight because of the vapor it the CW Tank and a spark.
Fly fast, live slow
 
soon7x7
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RE: TWA800 Fuel Tank Question

Wed Jun 03, 2009 12:42 pm



Quoting Propilot83 (Reply 15):

Just for the record...several types of missiles exist that have the potential of destroying a 747 with out even contacting the airfame...proximety missiles,etc. They don't have to be large at all, in fact very small as the airframe just has to be compromised and the breakup sequence will do the rest. Thats what can cause 50 gallons of JET A to mist, then result in a massive explosion. Travelling at 350MPH with exposed 1/16 th aluminum skin doesn't leave much to the imagination. The plane will peal apart like a banana. On the other hand, most of us, if not all of us...if anyone here believed the CIA climb video that a 747, despite cg. change and all the other crap...climbed another 3200 feet after the front 1/3 of the fuselage departed the airframe, and would have most definetely resulted in the shut down of engines #2 and #3 due to FOD ingestion, then you don't know as much about planes as you think. I can't imagine any aviatior on this site believes the CIA cartoon.
If a center wing tank JUST blew up then design flaws exist...the fleet should have been GROUNDED!...not only were they never grounded but had it been a design flaw, the same scenario would have played out many other times on many other 747's in many parts of the world. The fuel tank obviously blew, in fact ALL the fuel tanks blew....the wings opened up from explosive forces, not from aerodynamic forces although that didn't help either. The notion that other theories exist for the sake of making a buck is silly...Americans will try and make a buck on anything...thats what is great about America...right or wrong.
 
DH106
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RE: TWA800 Fuel Tank Question

Wed Jun 03, 2009 1:08 pm



Quoting Soon7x7 (Reply 20):
..........climbed another 3200 feet after the front 1/3 of the fuselage departed the airframe, and would have most definetely resulted in the shut down of engines #2 and #3 due to FOD ingestion,

Power isn't the issue, a 747 travelling at 350mph has a LOT of inertia. After the nose was blown off, the resulting gross rearwards shift in the CG would most definitely cause a pitch up. If you calculate the aircraft's kinetic energy at 350mph and then hypothosise a scenario where the aircraft then pitches up and climbs while the speed decays on the effects of gravity alone (converting it's kinetic energy into extra height or 'potential' energy) then the height gain would be of the order of 4000ft (neglecting the effects of drag etc - but then all 4 engines wouldn't instantly cease developing thrust either). I think 3200ft is entirely reasonable.
...I watched c-beams glitter in the dark near the Tanhauser Gate....
 
soon7x7
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RE: TWA800 Fuel Tank Question

Wed Jun 03, 2009 4:00 pm



Quoting DH106 (Reply 21):

On the basis of aerodynamic drag alone, all other forces will rapidly be cancelled out, drag and gravity will immediately overpower all other forces...an open cylinder, 20 feet wide by 26 feet high, minus 50% power, would create enourmous negative g's while rapid deceleration would negate any possibilty of a 3200 foot climb. Two friends of mine that were airborne in the area, one facing the event head on stated to me that upon the explosion the aircraft as much as stopped in the air and DROPPED...no climb existed...I've got over 5,000 hours flying non powered aircraft...aerdynamics are fairly important to me...a possible climb of 320 feet by inertia, figuring in all the other perameters, I'd accept that, but not 3,200 feet. Given the condition of the aircaft post nose separation...Virtually imossible.
 
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Faro
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RE: TWA800 Fuel Tank Question

Wed Jun 03, 2009 6:27 pm



Quoting Soon7x7 (Reply 9):
Someday the case will be unclassified and it will be interesting to follow up on that event. Pieces of that plane are still washing up on New York beaches as about 4 tons of airframe still remain underwater...

Interesting, I wasn't aware that there remained a "case" and that it was being kept away from the public eye. Is there any official notification of such retention, and by which public authority? How much more time remaining to declassification?

Faro
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Moose135
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RE: TWA800 Fuel Tank Question

Wed Jun 03, 2009 6:44 pm



Quoting Faro (Reply 23):
I wasn't aware that there remained a "case" and that it was being kept away from the public eye.

Officially, the FBI ended its investigation years ago, stating "No evidence has been found which would indicate that a criminal act was the cause of the tragedy of TWA flight 800." However, during the early stages of the NTSB investigation, the FBI collected large amounts of recovered materials, which they examined for evidence of a crime. For the most part, they did not release reports about those materials, nor have they turned over the materials to the NTSB or any other party, despite repeated lawsuits and Freedom of Information act requests.
KC-135 - Passing gas and taking names!
 
DH106
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RE: TWA800 Fuel Tank Question

Wed Jun 03, 2009 8:35 pm



Quoting Soon7x7 (Reply 22):
On the basis of aerodynamic drag alone, all other forces

Yeah...... fair point about the drag.
So where does CIA state the data for the reconstruction come from - was the FDR functional after the nose seperation ?
...I watched c-beams glitter in the dark near the Tanhauser Gate....
 
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Moose135
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RE: TWA800 Fuel Tank Question

Wed Jun 03, 2009 11:20 pm



Quoting DH106 (Reply 25):
So where does CIA state the data for the reconstruction come from - was the FDR functional after the nose separation?

No, the CVR and FDR both stopped working at the time of the initial blast. The CIA made up the video in order to attempt to show that the eyewitnesses didn't see what they saw. It's basically a cartoon.
KC-135 - Passing gas and taking names!
 
soon7x7
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RE: TWA800 Fuel Tank Question

Wed Jun 03, 2009 11:32 pm



Quoting DH106 (Reply 25):

The CIA data was constructed from Key Eyewitnesses. Some data from local ATC,(but not all). Statements from other pilots that were airborne. No data was retrieved from the airframe recorders that yield anything to hold onto as all power was terminated at the time of the mishap. 735 witnesses, about 200 or so were really grilled by the feds. All witnessed the same visuals despite their various geographical locations from the site. Some were engineers, pilots, and other professionals from all career levels. What the CIA cartoon set out to accomplish was to tell these witnesses "What They Really Saw". This animation includes the additional (impossible 3200ft climb). I'd like to get the staff of MYTHBUSTERS to bust that theory. I will get railed as always happens during these TWA800 threads, as a conspirator. I do believe that the center wing tank blew, so did the wing tanks...but from what? I know had I been surfing that night in those waters as I usually am, I would take to my grave the event as I witnessed it and would not allow any US Government official to CONVINCE ME that I saw something different.
One more point I find incredibly interesting. As I said, I have been surfing the waters off Long Island for 35 years. I'm a pilot, mechanic and aviation photographer. The night of the event, the Navy had many assets, Destroyers, Submarines and a P-3 Orian flying in the exact airpace with an "inop xpndr". Military asset flying in Long Island Airspace with no transponder.!?....Many witnesses reported sighting these military assets. Just south of Long Island exists MOA 105...a Military operating area that is sometimes HOT. This area is printed on the FAA issued VFR charts for all local pilots. While surfing off these beaches, I have on MANY occassions heard and felt explosive concussions.(spelling)? Grumman used to test equipment out there. Never had I heard of actual military ship sightings from these shores until the night of July 7, 1996. Two days later after the event, James Calstrom from the FBI on National television stated that NO LIVE ORDNANCE is ever being detonated off the shores of Long Island yet on the FAA charts it states..."Fly With Caution" while zone is Hot!...go figure

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propilot83
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RE: TWA800 Fuel Tank Question

Thu Jun 04, 2009 12:02 am

I dont think there was a dummy missile, there was actual reports indicating that the USS Normandie cruiser was in the area off the coast of New York, testing missiles and stuff. Why couldnt the possibility be that a faulty electrical wire can cause a spark in the center fuel tank with vapor fumes in the tank? Its possible! It might not have been a design flaw, there are hundreds of miles of wiring on a Boeing 747, mostly a lot more on the classic versions. There are many unsolved mysteries in the world that still have not been solved and probably will never be solved, life is not perfect, just because we couldnt find the faulty electrical wire that caused the explosion on TWA-800, doesnt mean that a missile shot it down just to make it seem like life is really perfect. Yea there could be the possibility that something else might have caused the crash, but like I said, the NTSB, FAA, and Boeing and the FBI werent going to spend million of tax payer dollars to not find out the truth. It just doesnt make any sense for the military or the U.S. Government to keep a secret if they had accidently shot the plane down, they would have just come forward just like they have with the Iranian air incident and as well as a lot of other incidents. Listen the technology was old okay, there were a heck of a lot of plane crashes in the 90's, so lets not blame the U.S. Government or the military for shooting down TWA-800 on accident, when it fact it wasnt true. Oh and by the way, nobody has even dared to answer my question about the Iranian Airbus that was shot down ACCIDENTLY by the U.S. Navy about 20-30 years ago in the Persian Gulf. Anyone have anything to say about that, the government didnt keep that a secret, it came forward and said "yes we thought it was a foe, however in the end.......innocent civilians happened to come in the crossfire instead!!!!
 
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Moose135
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RE: TWA800 Fuel Tank Question

Thu Jun 04, 2009 1:03 am



Quoting Propilot83 (Reply 28):
Oh and by the way, nobody has even dared to answer my question about the Iranian Airbus that was shot down ACCIDENTLY by the U.S. Navy about 20-30 years ago in the Persian Gulf. Anyone have anything to say about that, the government didnt keep that a secret, it came forward and said "yes we thought it was a foe, however in the end.......innocent civilians happened to come in the crossfire instead!!!!

What was your question about that shootdown? BTW, it wasn't an F-14 that shot it down, as you stated in Reply 15, it was shot down by missiles from the USS Vincennes, which claimed they thought they were firing on an Iranian F-14. I won't get into how to explain a state-of-the-art (it was 3 years old at the time of the shootdown) Aegis missile cruiser, mistaking an airliner, in an approved air corridor, squaking an appropriate transponder code, for an F-14.

The shootdown happened in broad daylight (approx 10:30am local time) in a busy sea lane, observed by Iranian ATC and mulitple US Navy ship radars, and the Iranians certainly weren't going to keep it quiet - they used the incident to attack the United States in the court of world opinion, and to gain a political advantage with other countries.

I'm not sure what that has to do with TWA 800. When TWA went down, many eyewitnesses reported seeing a streak of light rise from the surface of the ocean, culminating in the explosion at altitude. Following the explosion, the fireball fell downward to the ocean. Many pieces of debris were taken by the FBI for examination of a possible bombing, and yet, even after they publicly announced there was no evidence of a crime, they did not return the items to the NTSB, and they have consistently refused to release documentation of their findings. When the NTSB held their public hearings on the crash investigation, NONE of the eyewitnesses were permitted to testify. Instead, they played the CIA CARTOON, claiming that hundreds of eyewitnesses, which included military and civilian pilots, were mistaken about what they saw.

If there is nothing to hide, why is the FBI doing such a good job, 13 years later, of hiding their findings? I'm a former KC-135 pilot, and the son of a retired TWA mechanic - I've spent a lifetime around airplanes, and the story doesn't sit right with me. PhilSquares, a former military pilot, with thousands of hours in the 747, says the story doesn't sit right with him. But let's believe the half truths and partial information, since the CIA put together a cartoon that matches the official story.
KC-135 - Passing gas and taking names!
 
soon7x7
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RE: TWA800 Fuel Tank Question

Thu Jun 04, 2009 1:09 am

Your 100% correct, anything is possible. N93119 made its way around and was maintained by many, I believe Iran actually had two TWA 747's for a while and this was one of them. So yes...it is possible...what I don't buy is the methods the feds used to spoon feed the public a bowl full of pablum crap...j
 
soon7x7
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RE: TWA800 Fuel Tank Question

Thu Jun 04, 2009 1:15 am



Quoting Moose135 (Reply 29):

Moose...I never got a chance to reply to that segment, you stole my thunder...I remember that event clearly and I also remember that the were pissed, rightfully so...I also remember that the Iranians promised direct retrobution when we are least expected. Now I've been taught that they are a society that believes in an eye for an eye and a tooth fo a tooth. So in the case of TWA800...anything is possible. Just like Air France 447. I have my doubts that we will ever know the cause of this past diaster and speculation will be the closest any expert will come.
 
KE7JFF
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RE: TWA800 Fuel Tank Question

Thu Jun 04, 2009 1:23 am

I think the FBI and the NTSB did the best job with the limited information provided by witnesses, the wreckage, and the CVR/FDR.

I don't think it was a missile, but however, I think it probably is something else not in the evidence that you just had to be there to see.
 
soon7x7
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RE: TWA800 Fuel Tank Question

Thu Jun 04, 2009 2:49 am



Quoting KE7JFF (Reply 32):

Me thinks the NTSB should have been left alone to spearhead the investigation rather than the FBI and CIA. To me they seem to be sort of out of jurastiction. I can tell you that 20 minutes after the explosion occurred I was out at Francis Gabreski airport which was 6 miles north of the impact zone. Aside from the press the place was crawling with FEDS. This is eatern Long Island!...Where did all the Feds come from in 20 minutes? No TWA personel, No NTSB, no FAA...just Feds...That blew my mind...last time I saw Feds out there was when Al Gore flew in on Air force two, a 757. I flew out there every weekend for 21 years and was very familiar with what was normal at that airport and what was not...this was not. During press conferences Robert Francis (NTSB) was hardly allowed to speak, James Kalstrom was (FBI) was the spokesperson of the investigation. Understand lots of angst between the two. The press was caralled into obscure corners and spoon fed information. As we went out on the Coast Guard cutter...we were only allowed one mile distance from the Grasp and Grapple. This was more like a recovery of a space shuttle disaster rather than a civil transport plane. The whole deal stank of secrecy! For any of you out there that think I'm a cospiracy theorist think about the obvious. Historically the post crash investigation of TWA800 was not handled officially like any other plane crash investigation. If it simply was a center wing tank spark, then why the secrecy, why the feds, why not the NTSB running the recovery. AA 587 was not handled in the same manor...Swissair 111...not even Egypt air 767. If you lived here on Long Island during this event, you would have seen what I saw.
 
jwenting
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RE: TWA800 Fuel Tank Question

Thu Jun 04, 2009 5:18 am



Quoting Soon7x7 (Reply 33):
Me thinks the NTSB should have been left alone to spearhead the investigation rather than the FBI and CIA. To me they seem to be sort of out of jurastiction.

CIA was almost certainly only called in to provide some technical expertise other agencies didn't posess. They're barred by law from operating on their own inside the US.

FBI is normal. Every crash has the potential of being a criminal case (criminal negligence on the part of the maintenance crew, terrorism, pilot suiciding by flying into the ground, etc. etc.) as well as having LEOs on the scene makes it a lot harder for ambulance chasers and other scumbag lawyers to invent "evidence" for a ligitation case against everyone with a bit of money.

Of course as soon as any government agency is involved the idiot conspiracy theorists (of which there are a lot even here in a forum supposedly populated by people who know about aviation) flock to the scene and start shouting "coverup" of some "government conspiracy".

There is no conspiracy, there is no coverup, there is no missile that could have shot it down (yes, there was a cruiser in the general area but it was not within missile range by several hundred miles. Yes, there are submarine launched SAMs but those can't reach that high as they're solely designed to shoot down hovering ASW helicopters. And no, there was no mystery ship in the area with some super duper secret CIA missile either).
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Faro
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RE: TWA800 Fuel Tank Question

Thu Jun 04, 2009 9:06 am



Quoting Jwenting (Reply 34):
There is no conspiracy, there is no coverup, there is no missile that could have shot it down (yes, there was a cruiser in the general area but it was not within missile range by several hundred miles. Yes, there are submarine launched SAMs but those can't reach that high as they're solely designed to shoot down hovering ASW helicopters. And no, there was no mystery ship in the area with some super duper secret CIA missile either).

One question: in the below thread post, does the NTSB have a *right* to any supplemental reports or materials as have been requested from the FBI? Were these FOI requests/lawsuits filed by the NTSB or third parties? What will be the fate of these collected materials?

Quoting Moose135 (Reply 24):
Officially, the FBI ended its investigation years ago, stating "No evidence has been found which would indicate that a criminal act was the cause of the tragedy of TWA flight 800." However, during the early stages of the NTSB investigation, the FBI collected large amounts of recovered materials, which they examined for evidence of a crime. For the most part, they did not release reports about those materials, nor have they turned over the materials to the NTSB or any other party, despite repeated lawsuits and Freedom of Information act requests.

The chalice not my son
 
soon7x7
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RE: TWA800 Fuel Tank Question

Thu Jun 04, 2009 12:33 pm



Quoting Jwenting (Reply 34):

The way it worked before TWA800 was the NTSB would obviously be called in to kick off any and all plane incidents and accidents. If they suspected foul play they would then bring the FBI into the investigation. The NTSB would still remain the lead investigating party. In the case of TWA800, the FBI steamrolled over the NTSB and mandated they take a back seat, after the FBI/CIA was done with their findings, the NTSB was left to pick up the crumbs.
I love you guys that like to throw the "idiot conspiracy theorist" term around because your naive enough to believe that government is not capable of duping its people. The word CONSPIRACY exists because conspiracies exist. Regardless of this event being one or not, (I NEVER SAID IT WAS). I just don't believe many aspects of the final investigation and I'll tell you one very imortant factor. Many of the "Family Members" who lost loved ones no longer believe the center wing tank theory as over the years they have learned much from aviation experts and for various other reasons. I didn't read that, they told me themselves. You reside I suppose in the Netherlands. Other than what you read...what would you know? Here in America, especially in New York where the media is king, the government and the media go hand in hand, believe non of what you hear/read, and half of what you see...
Now the protocol for aircraft crashes in the US is that it becomes a crime scene immedietely until the evidence suggests it is not,...then the FBI turns over the investigation to the NTSB. Its like the 33 year old law student that was just put in place to run GM...what the heck does he know about automobile manufacturing?...it's all nonsense!  banghead 
 
PhilSquares
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RE: TWA800 Fuel Tank Question

Thu Jun 04, 2009 2:14 pm



Quoting Soon7x7 (Reply 36):
Its like the 33 year old law student that was just put in place to run GM...what the heck does he know about automobile manufacturing?...it's all nonsense!

Let me play devil's advocate. What did the past CEOs know about auto manufacturing?

Doesn't seem to me like it could make things worse!
Fly fast, live slow
 
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SEPilot
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RE: TWA800 Fuel Tank Question

Thu Jun 04, 2009 3:46 pm



Quoting Fr8Mech (Reply 3):
Not too sure about that. Standard procedure, on just about any aircraft, is tank-to-engine on take-off and landing.

I do not know 747 procedures, but this pilot had thousands of hours in the 741. I may have misremembered some of what he said, but the gist of it I remember clearly. I don't know how much he understood about the 747 systems, but he was absolutely the best instructor I ever flew with. I cannot ask him for clarification because he is now dead.

Quoting Euclid (Reply 5):
From what I remember from the programs I have seen about this crash, the only wires in the tank were for the fuel indicators, as quoted above. These were all low current wires that would not be able to spark due to the low current carried by them. No high current wires were routed through the tank due to the danger of sparking.

I believe that the NTSB thought that high voltage had shorted to these wires. If that happened, it would likely cause a spark. Whether or not it could ignite the fuel tank is a question for the Mythbusters.

Quoting Propilot83 (Reply 15):
If a missile had actually shot the plane down, the explosion would have been so big that the debris would have been no larger than the size of a car.

How do you know? I believe that a lot of anti-aircraft missiles (especially shoulder-fired ones) have very small warheads. It does not take much of an explosion to bring down an airplane. The bomb in PA 103 was perhaps a pound of explosive; it was hidden in a fairly small radio.
The problem with making things foolproof is that fools are so doggone ingenious...Dan Keebler
 
soon7x7
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RE: TWA800 Fuel Tank Question

Thu Jun 04, 2009 4:02 pm



Quoting PhilSquares (Reply 37):

Yeh, it's nothing new here in the states,...what ever happened to job qualifications? Gone are the days where you worked your way up the ladder as a result of good performance and knowledge gained.
 
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SEPilot
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RE: TWA800 Fuel Tank Question

Thu Jun 04, 2009 4:35 pm



Quoting Soon7x7 (Reply 39):
Yeh, it's nothing new here in the states,...what ever happened to job qualifications? Gone are the days where you worked your way up the ladder as a result of good performance and knowledge gained.

And let the Peter Principle run amok.
The problem with making things foolproof is that fools are so doggone ingenious...Dan Keebler
 
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Jetlagged
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RE: TWA800 Fuel Tank Question

Thu Jun 04, 2009 4:43 pm



Quoting PhilSquares (Reply 16):
Aircraft don't just blow up in the sky. The theories about the residual heat from ground operations and the shorting of the electrics just makes no sense.

So you think a spark in a tank full of highly combustible fuel vapour couldn't cause it to explode? Temperature is also important because it affects the vapour flashpoint. If the tank had not been hot on takeoff, it is doubtful that a spark would have caused an explosion. Fuel related explosions in aircraft aren't unknown, as I'm sure you will know, so I'm surprised you write the possibility off so easily.

Quoting Soon7x7 (Reply 20):
If a center wing tank JUST blew up then design flaws exist...the fleet should have been GROUNDED!...not only were they never grounded but had it been a design flaw, the same scenario would have played out many other times on many other 747's in many parts of the world.

Putting words in CAPS doesn't improve your arguments. That the 747 classic fleet was not grounded proves nothing. It's rare for an entire fleet to be grounded after any accident. All RR powered 777s are prone to the same problem that caused a BA 777 to crash at LHR, but none have been grounded. 737s weren't grounded after a design flaw was exposed in the rudder actuator. What the NTSB did after TWA800 was recommend all operators ensured the centre wing tank was freshly refilled with fuel before each takeoff. Grounding all 747 Classics would have been pointless overkill.

As for the 3200 ft climb, why do you think it was added to the reconstruction? The aircraft would not have stopped climbing instantly and perhaps the people who made the video over-estimated how far momentum would take it.
The glass isn't half empty, or half full, it's twice as big as it needs to be.
 
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RE: TWA800 Fuel Tank Question

Thu Jun 04, 2009 5:24 pm



Quoting Jetlagged (Reply 41):

So you think a spark in a tank full of highly combustible fuel vapour couldn't cause it to explode?

The point is that jet fuel vapor in normal circumstances is not highly combustible. It must be within a fairly narrow band of concentration, and this is only achieved at fairly high temperatures. That is why this is such an unusual event, assuming that this is indeed what happened. Personally I am not convinced, but have not seen a convincing case for an alternate explanation either. One thing I do believe, and that is that it is almost impossible to make everyone involved in a conspiracy keep their mouths shut.
The problem with making things foolproof is that fools are so doggone ingenious...Dan Keebler
 
PhilSquares
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RE: TWA800 Fuel Tank Question

Thu Jun 04, 2009 5:42 pm



Quoting Jetlagged (Reply 41):
So you think a spark in a tank full of highly combustible fuel vapour couldn't cause it to explode? Temperature is also important because it affects the vapour flashpoint. If the tank had not been hot on takeoff, it is doubtful that a spark would have caused an explosion. Fuel related explosions in aircraft aren't unknown, as I'm sure you will know, so I'm surprised you write the possibility off so easily

No I don't. The temp in the CW tank doesn't get that hot and there was no reason to think it would have been hot on this flight. In fact, the sister ship, which was owned by Evergreen was flown under the exact same conditions during the investigation phase and there was no appreciable increase in temp. The #2 pack was used during ground operations and again, there was no appreciable increase in temp of the CWT.

In addition, even though they were at a relatively low altitude, the air is significantly lower than at sea level. IIRC the airpressure is at 2psi at 13,000' when compared to sea level pressure. So, even though the same percentage of O2 is present, it is at a much lower volume than it is at sea level.

In addition, excluding KC-135 accidents where a tank exploded (they were all on the ground) the only other example of a fuel tank exploding while using Jet A1 is a PAL 737-300 (11 May 90) that had the center wing tank explode which subsequently ruptured the two wing tanks. The CW tank had not been filled in 3 months and the theory is there were vapors present when a spark from an unknow source ignited the fumes.

Since then, excluding the TWA accident, there were two accidents, one involving a Thai 737-400 on the ground and a Transmile 727 in BLR. However, in the Transmile incident the aircraft had a know fuel leak, so that isn't quite like the two 737 incidents.

So, yes, I find it extremely hard to believe the TWA 747 accident report.

Quoting Jetlagged (Reply 41):
so I'm surprised you write the possibility off so easily.

How can you reasonably say that? Where did I ever write I dismissed it easily? Please don't put your own interpretation on what I write. I don't know how much time you have in Boeings, but I stand by what I said. Aircraft just don't explode from the circumstances that were deemed the "most probable cause".
Fly fast, live slow
 
rwessel
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RE: TWA800 Fuel Tank Question

Thu Jun 04, 2009 8:14 pm



Quoting PhilSquares (Reply 43):
In addition, even though they were at a relatively low altitude, the air is significantly lower than at sea level. IIRC the airpressure is at 2psi at 13,000' when compared to sea level pressure. So, even though the same percentage of O2 is present, it is at a much lower volume than it is at sea level.

At 13,000ft, the air pressure is a hair under 9psi.

And didn't someone blow up a 737 center tank (on the ground) with a very low voltage spark with internal conditions similar to what was likely for TWA800?
 
PhilSquares
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RE: TWA800 Fuel Tank Question

Thu Jun 04, 2009 8:43 pm



Quoting Rwessel (Reply 44):
At 13,000ft, the air pressure is a hair under 9psi.

My mistake. At 18,000 the PSI is half of the sea level pressure.

Quoting Rwessel (Reply 44):
And didn't someone blow up a 737 center tank (on the ground) with a very low voltage spark with internal conditions similar to what was likely for TWA800?


I provided you all the fuel tank explosions. Again, there have been NO fuel tank explosions inflight.

IIRC, on the classic you could only use 2 packs on the ground. The preferred packs were 1 and 3. Neither would provide any heating to the CWT. In addition, the ground tests done in hotter conditions provided no evidence of thermal problems in the CWT.

The probability of having a fuel tank explode is very remote. The report just doesn't make any sense based on how the fuel system is designed.
Fly fast, live slow
 
SXDFC
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RE: TWA800 Fuel Tank Question

Thu Jun 04, 2009 10:34 pm

From what I remember hearing on the news, and reading in books the Boeing 747-131 N93119 came in from Athens,Greece which is a 10+ hour flight from ATH-JFK, which is why I believed they used the Center Fuel tank. I think they also used the fuel left over to run the APU while the plane was on the ground for a while, since it was delayed due to a mis-matched bag.

N93119:


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lowrider
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RE: TWA800 Fuel Tank Question

Thu Jun 04, 2009 11:01 pm



Quoting SXDFC (Reply 46):
. I think they also used the fuel left over to run the APU while the plane was on the ground for a while, since it was delayed due to a mis-matched bag.

APU fuel on the classic comes from the #2 (L Inboard) Main.
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soon7x7
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RE: TWA800 Fuel Tank Question

Thu Jun 04, 2009 11:52 pm



Quoting Jetlagged (Reply 41):

A full tank has less of a chance of exploding than one that is partially full. In the case of N93119, the night of July 17,1996, about 50 US gallons remained in the center fuel tank that measures 20'x20'x7'. The tank internally is vented for fumes and is also baffled. The fuel sensors and scavange pumps all are a function of low voltage wiring. For that amount of fuel to destroy a 747, atomization of the Jet A would be required to ignite the fuel. Considering the volume of the tank and the amount of fuel in it at the time...even the investigators revealed it would under those circumstances have been a LOW pressure event. (Sorry for the caps but its just how I emphasize stuff).
As for the 3200 ft climb...consider this. Since your an aviation person of sort, you would understand this. After the explosion, nose section 41 and section 42 departed the airframe at about 350 MPH. The section 41/42 is actually a lifting surface with the upper hump, also it was a steamlined object at the time of separation. That would have been the component that would have temporarily continued forward and upward before drag and gravity took over. The resulting FOD from the separation would have been ingested by #2and #3 powerplants which in fact did occurr as they found human tissue in both in addition to airframe FOD. At best you had an immediate failure of two powerplants or a 50% reduction in climb power...not to mention the incredible degree of aerodynamic drag a gaping 20'x26' open ended tube would create. Do you really think it continued up 3/4's of a mile?
About the time the 747, L-1011, and the DC-10 were up and coming, competition was strong to get wide bodies into the air. As a result of their haste, corners were cut and problems existed with all types and groundings did occur. The early JT9's had a habit of cracking and overheating on start ups. 747's were blowing tires all over the place. The AA DC-10 in Chicago caused a grounding. The MD-80 was grounded after the Alaska jack screw incident...the 737 almost was but was reconsidered as it would have crippled the airlines due to its high use. That was the suspected hard over rudder problem, USair #427. Other groundings have occurred...just getting to old to remember them all!


Quoting SXDFC (Reply 46):

The baggage delay you speak of was actually not really a bag mismatch. N93119 was supposed to ferry a spare engine under the wing on that flight but never made it to JFK in time. The wing mounted pod that they were to use remained in the corner of JFK's TWA hangar until AA took over TWA. Your correct in that the aircraft had come in from Athens the flight before. (My sources...friend worked at medical examiners office, friend worked for company that was to loan the engine spare, friends that were TWA mechanics at the JFK TWA Hangar that dispatched the plane that night).
 
soon7x7
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RE: TWA800 Fuel Tank Question

Fri Jun 05, 2009 12:15 am



Quoting Jetlagged (Reply 41):

As an aviator...can you or anyone here actually think that this has the ability to climb 3,200feet with a 50% power reduction?...forget the drag and gravity physics...
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