AD 2021-08-09 Prompted By The Discovery Of An Erroneous Value In Some Airplane Data Files

The FAA is adopting a new airworthiness directive (AD) for all Airbus SAS Model A330-323, -342, and -343 airplanes.

This AD was prompted by the discovery of an erroneous value in some airplane data files that are used for performance computations in the airplane flight manual (AFM). This AD requires revising the existing AFM and applicable corresponding operational procedures, as specified in a European Union Aviation Safety Agency (EASA) AD, which is incorporated by reference. The FAA is issuing this AD to address the unsafe condition on these products. This AD becomes effective April 23, 2021.

Supplementary Information: EASA, which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2021-0071, dated March 12, 2021 (EASA AD 2021-0071) (also referred to as the Mandatory Continuing Airworthiness Information, or the MCAI), to correct an unsafe condition for all Airbus SAS Model A330-323, -342, and -343 airplanes.

This AD was prompted by the discovery of an erroneous value in some airplane data files used for AFM performance computations. This erroneous value could result in the generation of an incorrect displacement drag in the take-off, accelerate-stop, and landing distance computations for particular situations. The FAA is issuing this AD to prevent these errors, which, in combination with one engine inoperative at takeoff, and with more than 50 mm dry snow at an airport within an AFM altitude between 8,000 and 12,500 feet, could lead to substantially reduced performance of the airplane and possible runway overrun, and consequent damage to the airplane and injury to occupants. See the MCAI for additional background information.

FMI: www.regulations.gov