India, April 8 -- Sometimes it pays to look into history. The same is the case with aviation. In 1991, a United Airlines plane smashed into the ground in Colorado. A few years later, in 1994, another plane, this time operated by the US Airways, nose-dived near Pittsburg. Around 157 people died in both the crashes but investigators from the United States' National Transportation Safety Board (NTSB) could not pin down the cause while they had their suspicions about the fact that a faulty aircraft rudder caused the problem. It was not until June 1996, when a third aircraft in Miami suffered another catastrophic event but managed to land safely, that investigators found out the truth. It was indeed a faulty rudder system, even though the manu...