|Dan's Papers - Long Island
Flight 800's Center WingTank
Pilot Who Flew The Plane Before Fateful Flight
Questions Official Conclusions
By Jerry Cimisi
It is no surprise to anyone on either side of the TWA Flight 800 controversy
that the National Transportation Safety Board declared at its final,
concluded hearing that the doomed plane that exploded four summers
brought down by an electrical spark which had ignited vapors in the
near empty center wing fuel tank.
Unfortunately, the NTSB said, its investigators have not been able to
the spark or wire that originated the explosion.
Among the many who contest the NTSB scenario is the last pilot to fly
and live to talk about it.
In a phone interview some days after the NTSB hearing, now retired TWA
Al Mundo, who had brought the plane into New York from Athens late
afternoon of July 17, 1996, explained not only the fuel system of the
but detailed his reasons why the center wing fuel tank would not have
the initiating cause of the explosion or explosions that destroyed
"We had left Athens that Wednesday morning," said Mundo. "The center
tank would have been full."
The center wing fuel tank is just that: a tank of fuel that is directly
the middle of the plane, beneath the passenger cabin.
Before going into the reasons why the fuel in that tank would not have
full on arrival in New York, Mundo explained the fuel system of the
"There are four main tanks of fuel, and two reserve tanks, to feed into
engines. If you're sitting in the cockpit, from left to right, you
the edge of the left wing, the number one reserve tank. Then, in sequence,
you have the number one main tank, number two main tank, number three
tank, number four main tank, then on the tip of the right wing, the
four reserve tank."
Mundo went on to say that the fuel flow of the plane is maintained so
the weight of fuel throughout the wing span will be balanced. Fuel
normally fed from each tank to its corresponding engine, although,
Mundo, when the combined fuel in the number one main tank and its reserve,
and the number four main tank and its reserve equals 25,000 pounds
is measured in pounds, not gallons), cross feeding fuel procedures
"We turn on both of the center wing tank fuel pumps. The center wing
two pumps, which work at twice the capacity of the other four main
pumps; their fuel flow is at fifteen pounds per square inch (psi),
wing tank pumps put out fuel at thirty psi.
"The cross feed valves are open, which allow fuel from the center wing
pumps to go to the number one, two, three and four engines. We shut
pumps from the number one main and its reserve and the number four
its reserve. We leave the pumps on from two and three as back up, though
because they are working at a rate only half that of the center wing
it's the center wing tank that is supplying fuel to the engines. At
point the two and three main tank feed is there as a backup. Anyway,
point the center wing tank is supplying fuel to all the engines.
"Eventually, as the center wing tank burns down to about 3,000-4,000
of fuel, the fuel begins to feed from the number two and three main
When the fuel quantity in the center wing tank gets low, a light for
pump begins to blink on the flight engineer's panels. "When the light
steady," said Mundo, "you turn off the pump for that light.
"Then you turn on the fuel/water scavenge pumps in the center wing tank
drain any liquid remaining. "
With the feed from the center wing tank now turned off, all four engines
being fueled from the number two and number three main tanks. At the
where there are about 25,000 pounds of fuel in each of the main tanks
number one main and reserve tanks and number four and reserve tanks
25,000 pounds each), so there is an even balance across the wing. Cross
feeding is terminated so that main tank one and its reserve will be
into its respective engine, number two into its respective engine and
Mundo went on: "When the plane landed in New York, the center wing tank
in the cockpit would have read zero pounds. It is possible that the
center wing tank fuel gauge could have read 300 pounds, which would
fifty gallons. This is not an unusual discrepancy."
In the first few days after the Flight 800 investigation Mundo asked
official what exactly the fuel use log had shown in regards to the
of fuel in the center wing tank upon arriving in New York. "He told
Mundo said, "that the log, which is placed in the Flight Document Envelope
and normally kept for ninety days, could not be found. This was an
He added that whatever level of fuel existed in the center wing tank
time would not be entirely composed of fuel. "All fuel contains some
It's the same with the gas in your car. Fuel is 6.7 pounds per gallon;
is heavier, 8.34 pounds, so the water goes to the bottom of the tank.
combination of water and fuel is what the scavenger pumps transfer
number two main tank."
Mundo said, "When 747's undergo a heavy maintenance check, and the nose
strut is deflated which tilts the plane downward, all the liquid in
center wing tank fuel goes to the front of the tank where it is drained
The amount drained is usually close to fifty gallons or around 300
In sum, the center wing tank of the plane that was about to become Flight
was empty or nearly empty before leaving New York in the late afternoon
to its evening takeoff to Paris.
Because of prevailing winds, planes usually carry more fuel when going
than when going east. "And then," said Mundo, "you also have to consider
distance youâ€™re travelling. Athens to New York is a lot
farther than New York
Now we get to one of the crucial points of the NTSB theory about the
volatility of the center wing tank. Mundo said, "There is the assumption
the NTSB that the fuel was heated by the air conditioning packs below
plane to a temperature that caused the fuel and fuel vapors to reach
This is an assessment with which the majority of the media concur. A
Times article from Wednesday, August 23, the day after the NTSB hearing
began, stated, "the nearly empty tank, which had been heated to an
state while the twenty-five year old jet sat baking in the sun for
three hours before taking off."
Mundo said, "I left two of the packs running, as was common practice."
added that with the flight time between Athens and New York at about
hours, "for at least nine and half hours the metal of the tank was,
altitude we had been flying, exposed to temperatures that were about
fifty-five degrees Celsius. Now metal will cold soak ” when your car
outside through the night in January you know it takes the metal some
"This is something they should have tested, but they didn't, exactly.
NTSB flew a plane across the continental United States, trying to duplicate
the conditions of the Athens to New York flight, but in the summer
over the land would be warmer than over the North Atlantic” and of
the plane would not be in the air for as long as on an Athens to New
run. Nobody knows exactly what the temperature in the fuel tank was
Flight 800 took off from New York. Commander Donaldson took a reading
747 at Kennedy the summer after the accident, and he found the temperature
the fuel drained from the center wing tank which had been on the ground
equivalent amount of time as 800 was, to be a degree above the ambient
[outside] tempertaure." (Retired Navy Commander William S. Donaldson
a longtime critic of the government's investigation of Flight 800.)
"Flight 800 took off for Paris at about 8:15 p.m. on the evening of
1996. A nearly empty tank has more fuel vapor than a tank that is full.
Government investigators speculate that the vapor-ridden center wing
tank was ripe for an explosion” instigated by the as-yet unfound electrical
But Mundo pointed out that the center wing fuel tank is vented to relieve
pressure inside the tank. "With an aircraft in flight," Mundo said,
a Venturi effect over the vent outlet. The more the speed, the less
pressure. When you're in a car and someone's smoking and you open a
the air pressure outside is less than the pressure inside and the greater
pressure inside pushes the air outside; the smoke will be sucked out
car. The air rushing outside the plane would create a great suction
should have decreased or eliminated any buildup of vapor in the tank."
* * *
Former TWA pilot Al Mundo then talked about another aspect of the electrical
spark theory: on Good Friday, 1995, when he was flying the plane that
become Flight 800 in July, 1996, the aircraft was struck not once but
The plane did not explode.
"We were descending into Rome. We were at about 13,000-11,000 feet.
were two strikes of lightning, about three minutes apart. There was
bang, and a yellow flash; initially there was no indication of anything
in the cockpit."
But a photoelectric cell activated an inerting gas whose purpose was
smother any fire or smouldering that could be caused by an electrical
This was done on the first lightning strike.
Mundo said, "Upon landing it was discovered there was not only substantial
damage to the right wingtip, it was also found that an electrical charge
gone all the way into the wing area, causing circuit breakers in the
to pop and the wheel brake temperature indicators to register full
the brakes had scarcely been used. It is quite evident from this that
strong surge of electricty went through the wing.
"The damage incurred was extensive. The plane was out of service for
But despite the damage that had been inflicted by the two lightning
the plane was able to land safely. The inference is obvious: if the
that expolded fifteen minutes out of JFK in the summer of 1996 was
down by an electrical spark igniting the center wing fuel tank, why
two lightning strikes, which would certainly supply infinitely more
to the electrical system of the plane than the theorized stray spark,
the aircraft to be blown apart?
Early on in the Flight 800 investigation, Mundo learned that there had
sooting found on the right wing vent system. "It seemed strange to
me that if
the explosion was initiated by the center wing tank, why would there
sooting on both sides of the wing? I contacted personnel in the investigating
team and suggested they check those records from the 1995 flight to
if the sooting came from the lightning strikes. I was later informed
records could not be located."
Mundo was questioned by investigators "about five days after Flight
said, but the extent of the questioning was solely on the character
Athens to New York Flight. The former pilot continues to feel that
investigators have not pursued the obvious lines of inquiry raised
or, if they have, such tests or studies have not been made public.
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