Sterile flight deck rule

[1] One such accident was Eastern Air Lines Flight 212, which crashed just short of the runway at Charlotte/Douglas International Airport in 1974 while conducting an instrument approach in dense fog.

The NTSB determined that the probable cause of the crash included the flight crew's failure to enforce a sterile cockpit during the final preflight checklist procedure.

Flying demanded constant attention, and the wind and engine noise in a slipstream-blasted open cockpit all but drowned out normal conversations.

[4] As aviation technology developed through the postwar period, increased comfort and sound reduction gradually created a more office-like environment, which is more conducive to distractions.

[5] The introduction of the Cockpit Voice Recorder as an objective onboard observer played an important role in the assessment of the problem during accident investigation by the NTSB, and eventual implementation of the rules by the FAA.