Within less than a month, the European Union Aviation Safety Agency (EASA) has issued two airworthiness directives addressing issues detected in certain members of the Airbus A320 family – the A321neo and A320neo. The issues, although of different origins and appearing under specific conditions, relate to the aircraft’s angle of attack protection and could potentially lead to an excessive pitch scenario, the agency stated. Some aviation professionals have noted that the issue in both cases is similar to the one that the MCAS software on the Boeing 737 MAX was developed to address.

In July 2019, the EASA issued an Airworthiness Directive (EASA AD 2019-01-71) alerting operators of the A321neo of a weakness in the angle of attack (AoA) protection. The issue, identified during analysis of the behavior of the elevator and aileron computer, was described as having the potential to lead to excessive pitch attitude under “certain flight configurations and in combination with specific manoeuvres commanded by the flight crew”.

The agency ordered operators of the A321neo to revise their flight manuals according to temporary revisions (AFM TR) developed by Airbus. That particular directive, considered as an “interim action”, has since been revised and re-published on July 31, 2019 (EASA AD 2019-01-71R1), commanding operators of the aircraft type to comply with the manufacturer’s recommendations within a 30 day ‘window’ starting August 7, 2019.

On the same day, July 31, 2019, the authority released another directive (EASA AD 2019-01-89), addressing a similar issue with the A320neo, detected during “analysis and laboratory testing of the behaviour of the flight control laws” of the aircraft type.

Airbus clarifies pitch up scenario

A spokesperson for Airbus told AeroTime that this latest issue was identified during tests of a new in-development flight control computer on the A320neo. The manufacturer also confirmed that, as in the previous case, the problem affecting the A320neo results in reduced efficiency of the AoA protection when the aircraft is set in a “remote combination” of circumstances, as previously mentioned in the EASA AD.

Perhaps aiming to distance itself from the AoA problems on the Boeing 737 MAX, Airbus highlighted that there are “clear dissimilarities” between the issues affecting its A320neo/A321neo aircraft and “other scenarios currently being discussed, which are affecting aircraft other than Airbus aircraft types”. The manufacturer also stressed that despite the similarities between the A320neo and A321neo cases, “there are clear differences specific to the A320neo”.

The European Union Aviation Safety Agency (EASA) has alerted operators of the Airbus A321neo of a potential “excessive pitch” problem. The issue, as many aviation professionals have noted, is similar to the one that Boeing’s MCAS software on the 737 MAX was developed to address.

The issue affecting the A320neo, as the plane maker explains, requires a combination of four conditions which are:

·       aircraft at a significant Aft CG (Center of Gravity);

·       sustained and continuous deceleration;