Airline pilots are banned from chit-chat during take-off and landing because of a little-known rule.
The Sterile Cockpit Rule requires pilots to avoid non-essential conversations during critical phases of a flight, which are normally below 10,000 feet.
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Eating meals and non-essential communications with cabin crews, as well as reading non-essential publications are also banned.
The regulation was introduced in 1974 after an Eastern Air Lines crash when the flight fell short of the runway and killed 72 people. Despite the poor visibility due to heavy fog, investigators determined the cause was, in part, due to "the flight crew's lack of altitude awareness at critical points during the approach" and put this down to "poor cockpit discipline".
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