Unknown factor in jet crashes.

The article discusses several factors causing crashes of airplanes in the U.S. Among the recent jet crashes were a Boeing 720B fan jet of Northwest Airlines, a United Air Lines (UAL) 720, and a Trans-Canada Air Lines DC-8. It enumerates factors such as the weather, lightning and the jet fuel mixture of kerosene and JP-4 combination of kerosene and gasoline. The article also concludes that question remains whether aerodynamic flaws or faulty techniques of flying in turbulence played a role in the accidents.