Page:CAB Accident Report, Eastern Air Lines Flight 21.pdf/24

 in men or equipment and to anticipate as far as possible the occurrence of human error or mechanical defect so that measures to prevent them or avoid their potentially tragic effects may be taken. It is the established practice of most of the major air carriers to provide a definite procedure by which all essential instruments and controls are checked at certain specified times during operation. This is usually accomplished by means of a check list upon which the instruments and controls are listed and is so firmly established as to be a matter of routine. Had such a formal procedure been in effect at the time Trip 21 was performing an instrument approach at Atlanta, a routine check would have revealed such an error in altimeter reading as appears to have been involved in this case. If, for some reason, it had not been possible for both officers to receive the setting relayed from the field and thus to check the instruments, a comparison of the readings on the two altimeters would have revealed a material discrepancy. However, in the absence of a formal procedure, it is entirely possible that an originally erroneous setting made by the officer who received the message from the ground station could escape unnoticed by the other officer. Therefore, even though Captain Perry did not adequately perform the duties incumbent upon him by failing to check carefully the altimeter settings before commencing a let-down procedure in complete reliance upon one of them, it is also apparent that Eastern did not exercise the requisite degree of caution by failing to establish a cockpit procedure to guard against just such occurrences as probably befell Trip 21 at Atlanta.