Operators of Airbus A321neo aircraft, including Air New Zealand, have been alerted by European aviation safety regulators to circumstances in which the nose of the plane could pitch up.
A European Union Aviation Safety Agency has warned the behaviour of the elevator aileron computer installed on A321neos can cause "excessive pitch attitude" that could result in "reduced control of the aeroplane".
The fault is most likely to occur on the final approach phase, UKAvitaiton.news reported, particularly if a "hard manoeuvre" is attempted, such as a large correction to the aircraft's angle of attack (AoA).
The temporary revision instructs airlines not to load their A321neos with a centre of gravity as far rearward as currently permitted so the weight is not towards the rear of the aircraft and the directive says they must change the aircraft flight manuals accordingly.
''Analysis of the behaviour of (a computer) installed on A321neo revealed that excessive pitch attitude can occur in certain conditions and during specific manoeuvres.
"This condition, if not corrected, could result in reduced control of the aeroplane,'' the directive from the agency says.
Air New Zealand says it has been advised of the potential problem which could affect planes with excessive tail-heavy loading.
''We don't load our A321s in this way, so the issue has no impact on our operations,'' a spokeswoman said.
This country's Civil Aviation Authority has also been contacted for comment.
Air New Zealand began adding the first batch of seven A321neos to its fleet last November and the aircraft are used on short-haul international flights, including across the Tasman.
The fault is not seen as serious as the flight control computer fault that has grounded the Boeing 737 Max aircraft that resulted in two fatal accidents claiming 346 lives.
FlightGlobal also reports that the crew would be able to react to this pitch-up to bring the aircraft immediately under safe control.
There would be no automatic take-over of manual crew input by an automatic aircraft system compared to the Boeing 737 MAX feature.
EASA has ordered operators of the A321neo to amend the flight manuals accordingly, within 30 days.
The order covers both those powered by CFM International Leap-1A and Pratt & Whitney PW1100G — which Air NZ has.
Seven temporary revisions to the flight manual have been issued, FlightGlobal reports. EASA says the safety measure is an interim action and could be followed by further requirements.
Air New Zealand is buying 13 Airbus neo aircraft (seven A321neos and six A320neos) to replace the A320 fleet that currently operates Tasman and Pacific Island services and a further seven Airbus A321neo for domestic network growth.
The A321neos are longer than A321s with 214 seats - 46 more than the airline's current international A320 fleet.
The A321neo is the biggest of Airbus' narrow-body fleet.