Danger In The Skies?

It's either an uncanny run of bad luck or a warning sign that something may be dangerously wrong. And federal investigators are pressing Trans World Airlines to find out.

In the past eight days TWA planes have made five emergency landings in a string of engine-related problems. The most bizarre incident happened Tuesday over Miami. Just after TWA Flight 4 took off for New York, an engine blew apart spewing chunks of hot metal onto cars below, reports CBS News Correspondent Bob Orr.

"It sounded like hail, very large hail. When we came out it was raining metal," said one woman.

The crippled MD-83, with 100 people aboard, turned around and landed safely.

The series of failures started July 11 when a TWA 757 lost oil in one engine and had to put down in Omaha, Neb.

The next day, a more serious incident occurred. Flight 379 was forced to land at a Missouri Air Force Base after an engine exploded -- filling the cockpit and cabin with smoke.

Three days later, on July 15, a TWA flight from San Jose had to turn around after an in-flight engine failure. And on Wednesday, just a day after the Miami metal shower, another TWA jet made an unscheduled landing in Wichita after a cockpit light warned of an engine oil problem.

Now, National Transportation Safety Board investigators are looking at the damaged engines and FAA inspectors are going over TWA maintenance procedures looking for any common threads that may signal a real problem.

Engine failures are fairly common and usually don't draw much attention. But, TWA - now a part of American Airlines - only carries 4 percent of U.S. air travelers. As one investigator puts it TWA doesn't have enough flights to have that many problems.

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