had one-off events fuel tank explosions, cargo door failures, things like that. there are horrific examples. crash of twa flight 800 in 1996 believed initially to be terrorism was later determined to have been an explosion of flammable vapors in a fuel tank. japan airlines flight 123, the 1985 crash considered the single deadliest accident in aviation history, more than 500 killed. it was determined that a previous tail strike had damaged the plane s rear pressure bulkhead and the repair was faul faulty. a similar thing happened to this russian aircraft. in 2001 this plane s tail struck a runway while landing. it was repaired and an official of the airline says the plane had been checked thoroughly for cracks. but safety experts are telling us tonight it is possible that a defect in the repair was simply not visible and a crack could have spread very rapidly during the time this plane might have been dissdisintegrating, wolf.
structural failures, how common is it it s repair or maintenance related. we re finding more and more where it s repair related. there were at least two suicides in the wake of this incident. a japan airlines employee who was working with victims families and an inspection engineer who issued a certificate of air worthiness for the doomed plane after the 1978 tail strike. to this day, jal 123 remains the deadliest single aircraft accident in the history of aviation. we ve seen the disastrous results of airplanes not properly repaired, maintained or inspected. japan airlines flight 123. american flight 191. aloha flight 242. we ve also seen what can happen when a plane has a design flaw but those flights are the exception, not the rule. every day, 3 million passengers
20,000 feet, which is where airplanes experience the most pressure on the vessel itself. at that point, they received a door warning, that a door was ajar, which turned out not to be the case. we ve already seen how an airplane s fuselage expands as the plane goes up and contracts as the plane comes down. the altitude with the greatest pressure differential between the pressurized inside of an aircraft and the unpressurized atmosphere outside is right around 24,000 feet. that s where jal 123 experiences an explosive shock. a massive decompression for reasons that they didn t know. but the crew did not realize the amount of damage they had sustained until very quickly, the airplane became less and less controllable to the point that it was no longer controllable at all. that would be a nightmare scenario for a pilot. what the pilots don t know is a critical piece of the 737
as we ve seen, structural failure on airplanes can be caused by inadequate inspections, faulty maintenance practices or design flaws buried deep within the guts of these giant machines. but the deadliest single plane crash in history, a 747 that crashed into a japanese mountainside, had another cause entirely. august 12th, 1985, japan airlines flight 123 has a staggering 524 people on board. the plane is set to fly from tokyo to osaka. this workhorse of a jet makes the one-hour trip several times a day. it s like flying from new york to boston.
the tremendous force blows the vertical fin and other parts of the sail section right off the giant 747. critical hydraulic lines are severed in the process. the first officer makes several radio calls that says that we re in uncontrollable flight. we do not have control of the airplane. they re fighting literally for their lives. the airplane starts to go into what they call a pitch oscillations, up and down, as well as a dutch roll. the airplane starts to swing back and forth. and no matter what the pilot tries to do as far as flight control inputs, he s not having an effect. the pilots fight desperately for control of the airplane for 32 terrifying minutes. they manage to keep the plane aloft, but with no hydraulics, they can t control the plane s up and down or side to side movement. eyewitnesses on the ground later report that the plane was flying like a staggering drunk. as jal 123 enters a mountainous