An up-to-par episode about a Grumman Mallard built in 1947 that lost a wing and crashed into the Atlantic just off Miami Beach in 2005, losing all 20 people aboard. It came as a shock to the public. Chalk's Ocean Airways had been ferrying people -- mostly high end people -- back and forth from Bimini and the Bahamas to Miami since the airline was founded in 1917. This was the airline's first air crash and, as it turned out, it's own death knell.
The investigation was the kind that would bore me to tears. They had to go over fifty years worth of repairs, major and minor, looking for some reason that the wing had separated from the rest of the airplane. But they did find it.
Business had been poor for some years at Chalk's and cost-cutting measures were implemented, including winnowing the list of mechanics. Serious problem were patched over, and when the patches failed, new patches were applied. The pilots recognized the gravity of the issue, had discussions, and some resigned.
The ultimate cause was found to be metal fatigue. There's nothing high tech about metal fatigue. If you take a piece of wire, a paper clip, and wiggle it back and forth long enough, it separates. That's what happened to the wing. On the ground, wings droop slightly. In the air, wings are bent upward at a slight angle. In other words, with each take off and landing, the wings are being bent back and forth.
The airline finally collapsed, with most being sorry to see the end of a business with such a long tradition.