Swiss investigators believe an Airbus A321 sustained a tail-strike at Geneva after a pilot mistakenly believed the aircraft had bounced on landing.
The Swiss International Air Lines jet (HB-IOC) had touched down on runway 05 following a service from Zurich on 9 March 2014.
Swiss investigation authority SUST states that the flight had been uneventful and that the aircraft made contact with a 1.4g impact.
The first officer felt, however, that the touchdown had been “unusually hard” and believed the aircraft had momentarily become airborne again.
SUST says, however, that this was “not the case” and attributes the erroneous interpretation to lack of experience. The first officer had just over 200h on A320-family jets, from 341h total flying time.
In response to the perceived bounce, the first officer initiated a go-around, but pulled her side-stick to the rear stop. The thrust levers were advanced to the take-off position.
SUST notes that the two side-sticks are not linked and that the captain, as a result, did not receive timely tactile feedback regarding the position of the first officer’s side-stick.
The crew training manual for the aircraft warns that a bounced touchdown is among the main reasons for tail-strikes, and cautions against excessive rotation rates in the event of a go-around close to the ground.
Owing to its length, the A321 is susceptible to tail-strikes at a pitch attitude of 9.7-11.2°, depending on whether the landing-gear is fully compressed.
As the aircraft climbed away during the go-around, air traffic control inquired as to whether the jet’s tail had contacted the runway, but the first officer responded: “Not that I know.”
The aircraft suffered damage to the underside skin of its aft fuselage but completed a second approach to runway 05 and landed without further incident. None of the 78 occupants was injured.
SUST found that software modifications to the flight control computers, designed to reduce the risk of tail-strikes, had not been implemented on the aircraft involved.