WASHINGTON — Airbus is requesting that the U.S. Federal Aviation Administration (FAA) approve the emergency descent performance of its A321XLR model based on the standard A321neo, claiming that the aerodynamic alterations to the long-range version will only have a minimal impact. 

The aircraft manufacturer asserts that flight-test data and analyses demonstrate the A321neo can descend from its certified ceiling of 39,800 feet to 10,000 feet in 2.67 minutes.

The A321XLR has undergone several high-speed performance enhancements, such as reprofiling the inboard flaps, optimizing the belly fairing and aileron droop, and redesigning the flap-track fairings. In a communication to the FAA, Airbus states that the A321XLR's total drag in clean configuration is reduced by around 0.7% compared to the A321neo, due to improvements in the flow topology on the upper wing surface.

However, during an emergency descent, the flow changes significantly as air braking is deployed, resulting in a substantial increase in drag. Airbus argues that the aerodynamic improvements are unlikely to materially affect the A321XLR's descent capability compared to the A321neo, and the two models can be considered equivalent.

Airbus highlights that the A321XLR and A321neo will share identical flight controls for emergency descent, pressure-control systems, limit speeds, and engines. Therefore, it asserts that the XLR should be granted the same compliance status as the A321neo in regard to pressurization regulations.