Секунды до катастрофы Comet Air Crash (2004–2012) watch online HD

1954.

The De Havilland Comet, the first jet airliner in the post-war years, built on aerodynamics discovered by the military, almost twice as fast as its nearest competitor. And what a gorgeous airplane it was -- long and sleek, its four engine tucked up neatly against the hull, the air intakes inconspicuously faired into the wings. The tail fin was straight up and its wings were only partially swept back, but even that was a revolution. It was a thing of beauty. No other airplane of the time looked so prepared to fly at high altitude and high speed. The execs at Boeing must have been sweat drenched.

It was not, however, a joy forever. It hadn't been in service long before two lethal crashes occurred. Since the flying conditions in both cases were difficult, weather was blamed for the accidents. The weather couldn't be blamed for what happened to BOAC flight 781 en route Rome to London. It blew apart in mid air and crashed in the Mediterranean near Elba, killing all aboard.

Investigative techniques and equipment were crude in 1954. No Cockpit Voice Recorders, no Flight Data Records, no transponder, and most of the airplane at the bottom of the sea. Churchill orders the Navy to recover the wreck, the Comet program was that important to Britain's air industry. The accident received additional publicity because one of the passengers was the renowned British journalist and historian, Chester Wilmot. While flight 781 was still being investigated, yet another Comet fell apart over the sea. Flights were halted at once and all Comets were grounded.

I'll skip the details except to say that in 1954 the analytical techniques were primitive by today's standards. Still, the analysis was amazingly precise in its application and findings. It boiled down to metal fatigue. The Comet had a thin aluminum skin into which windows had been riveted. These were the points at which the fuselage was weakest. Cracks began to spread from the window rivets to the rest of the skin.

There's nothing mysterious about metal fatigue. If you take a thin piece of wire and twist it back and forth, it eventually softens and breaks in two. Instead of the Comet's fuselage being yanked back and forth, it was stressed with every take off and landing. On take off and during rise to altitude, pressure in the cabin increased while the air pressure in the atmosphere outside decreased. The reverse was true at each landing. However slightly, the Comet's skin expanded and contracted with every flight until it failed.

This was an important accident. It led to the disappearance of the De Havilland company, whose jet airliner -- the first ever -- was replaced by Boeing, which has more or less dominated the skies since then.

As usual, the episode is very nicely done indeed.