A320, vicinity Liverpool UK, 2018
A320, vicinity Liverpool UK, 2018
On 24 June 2018, the Captain of an Airbus A320 which had just departed Liverpool inadvertently selected flaps/slats up when “gear up” was called. The error was quickly recognised and corrective action taken but the Investigation was unable to determine why the error occurred or identify circumstances directly conducive to it. It noted that they had previously investigated four similar events to the same operator’s A320s which had occurred over a period of less than 18 months with the operator introducing a requirement for a “pause” before gear or flap selection to allow time for positive checking before selector movement.
Description
On 24 June 2018, an Airbus A320 (G-EZOZ) being operated by EasyJet on a scheduled international passenger flight from Liverpool to Paris CDG had just taken off in day VMC when the Captain inadvertently selected the flaps/slats up instead of the gear when “gear up” was called by the First Officer. Corrective action followed promptly and the flight was completed without actual risk of loss of control and without further event.
Investigation
An Investigation was carried out by the UK AAIB who noted that they had previously investigated four similar flap mis-selection events which had occurred to A320s of the same operator between February 2016 and March 2017. The aircraft operator provided relevant QAR data to assist this latest Investigation.
It was noted that the 33 year-old Captain, who had been PM for the flight involved, had a total of 6,086 flying hours of which all but 172 hours were on type. The flight involved was the crew’s third sector of a four sector day and no evidence that fatigue had affected the performance of the crew was found.
It was established that after a 62.6 tonne gross weight takeoff from runway 27 at Liverpool with a flap 1+F configuration (an 18° leading edge slat extension and a 10° trailing edge flap extension), the First Officer’s call of “gear up” had been followed by the Captain’s SOP response “gear” as she placed her hand on the flap lever and selected it to the flap 0 position at 181 feet agl and 162 KCAS. Having done so, she had quickly realised her error and re-selected flap 1 which, in line with system logic in the prevailing situation, had resulted in the leading edge slats returning to the 18° extended position but had not interrupted the trailing edge flaps transition to 0. The landing gear was subsequently selected up passing 330 feet agl and passing 600 feet agl, pitch attitude was reduced to 10°. The flaps were eventually selected to 0 a second time passing 1650 feet agl with the speed increasing through 200 KCAS and had reached 0 by 2000 feet agl.
It was noted that the aircraft operator’s SOP for gear retraction was substituted for the operator’s SOP for flap retraction with both reliant on the PM checking their own actions in response to the instruction given by the PF. It was also noted that after a series of earlier after takeoff flap mis-selection events, the operator had introduced a pause before initiation of gear or flap lever movement to ensure “that the PM cognitively confirms the proper lever has been selected”. The notification of this procedural change was noted to have stated that this pause would also allow the PF to “intervene if he or she notices an incorrect selection is about to be made” but did not place any requirement to actively check that the PM’s response to their instruction was correct.
The Investigation noted that in the aftermath of the series of previous similar events, the aircraft operator had reviewed their responses prior to this latest event, which had included crew training in ‘active monitoring’ and on aircraft handling in low energy states at low altitudes and concluded that no further Safety Action was necessary. It was also noted that the Captain involved stated that “in future she will employ a longer pause to double check the correct lever selection and allow time for the pilot flying to intervene should they see the wrong lever has been selected”.
The Final Report of the Investigation was published on 10 January 2019. No Safety Recommendations were made.