Originally Posted by 450knotOffice

There IS a history of at least one other jetliner being taken down by a fuel tank explosion.

In 1963 a Pan 707, "Clipper 214", from BWI to PHL, was hit by lightning while holding at 5000 feet west of PHL waiting for a cell to clear the airport. Fuel vapors in a reserve tank in the left wing were ignited, which ultimately resulted in a large portion of the left wing departing the aircraft. The 707 broke up and crashed. Changes were made to the certification regs as a result of that flight.

While the root causes of the fuel tank explosions on the TWA 747 and Pan Am 707 were different (lightning versus a short circuit), the result was the same.