Flight 9268

Recently, a Russian airliner, Metrojet Flight 9268 flying at 31,000 feet, broke into pieces and crashed in a remote area of Egypt's Sinai Peninsula, killing the 224 people on board. An official from the airline said the crash must have been caused by “an external influence” because planes don’t break apart in midair.

The same official, Alexander Smirnov, also said, “We exclude technical problems and reject human error" as possible causes of the crash.

Why would an airline official reject human error as a possible cause of an accident? According to an FAA report, 70 to 80 percent of civil and military plane crashes are due to human error. Sometimes the pilot makes a mistake. Sometimes maintenance people make a mistake.

In 1985, Japan Airlines Flight 123 experienced explosive decompression when an improper repair to the plane’s aft pressure bulkhead led to failure of the bulkhead which then blew the vertical stabilizer off the airplane. The plane  subsequently crashed, killing 505 people. The pressure bulkhead had been damaged seven years earlier during a tail strike. A tail strike happens when the plane is landing or taking off and the pilot rotates the nose too high, causing the tail of the fuselage to strike the runway. A repair was improperly made, and for seven more years the airplane flew without problems, until the defective repair failed.

Like the Japanese airliner, the aircraft called Metrojet Flight 9268 experienced a tail strike that caused significant damage. Was the repair made improperly, causing the aft pressure bulkhead to fail years later? While a few planes have been brought down by “an external influence,” the number is very small compared to the number of planes that have crashed due to technical problems or human error. Ruling out the factors that have caused 99 percent of all airplane crashes – and ruling them out at the beginning of the investigation – is wishful thinking in the extreme.