Easyjet A319 at London on Jul 13th 2021, rejected takeoff above V1 due to disagreeing airspeeds

Last Update: January 13, 2022 / 11:29:04 GMT/Zulu time

Bookmark this article

Photo of Easyjet G-EZBD, Airbus A319 — Easyjet G-EZBD, Airbus A319 (Photo credit: Jeroen Stroes Aviation Photography / Flickr / License: CC by)

Incident Facts

Date of incident
Jul 13, 2021

Classification
Report

Airline
Easyjet

Flight number
U2-9002

Departure
London Luton, United Kingdom

Destination
London Luton, United Kingdom

Aircraft Registration
G-EZBD

Aircraft Type
Airbus A319

ICAO Type Designator
A319

An Easyjet Airbus A319-100, registration G-EZBD performing flight U2-9002 from London Luton,EN to London Luton,EN (UK) with 2 crew, had been in long term storage since Jun 14th 2021 and was scheduled for a non-revenue verification flight. The crew had briefed in particular to watch for airspeed discrepancies remaining below 20 knots during the takeoff run. The aircraft lined up runway 07 at intersection H for departure and commenced takeoff. When the commander's (32, ATPL, 4,412 hours total, 4,272 hours on type) ASI showed 60 knots the first officer's ASI showed 40 knots. When the commander's and standby ASI increased through 80-90 KIAS the first officer advised his ASI was still showing 40 KIAS. The commander checked they were still on the centerline and how much runway remained, then checked his ASI which was already above 100 KIAS and increasing quickly. As V1 had been calculated at 109 KIAS, the commander made a quick decision and called STOP. Takeoff was rejected, the aircraft came to a stop about 350 meters before the end of the runway.

The AAIB released their final bulletin concluding the probable cause of the serious incident was:

The aircraft suffered an airspeed discrepancy resulting from a blocked pitot probe. The crew recognised the fault and the takeoff was rejected.

The AAIB summarized the operator's examination of the aircraft:

The aircraft pitot systems were examined after the event and all appeared to be satisfactory. All three pitot systems were flushed in accordance with Aircraft Maintenance Manual (AMM) procedures. During the flush some debris was seen to be removed from the co-pilot’s pitot system. The material was not recovered so the quantity and constituent of the debris could not be determined. Following the flush procedure, all the aircraft pitot systems were leak checked in accordance with AMM procedures and all were satisfactory.

The AAIB analysed:

The aircraft suffered a discrepancy between airspeed systems, which was identified during the takeoff roll through routine flight crew cross checks. Prior to the flight the crew had discussed company documentation relating to previous airspeed discrepancy events on other aircraft and so they were alert to the possibility. The co-pilot noticed a discrepancy between his PFD and the ISIS at approximately 60 kt. He rechecked the indications and confirmed that the PFD indications had remained at 40 kt and informed the commander by which point the ISIS was indicating between 80 and 90 kt. The aircraft was light and therefore accelerating very rapidly. The commander looked briefly across the cockpit to confirm the situation and then called “Stop.” The aircraft airspeed was above 100 kt and increasing rapidly. As a result of the rapid acceleration, by the time the commander was able to articulate his order, the RTO was initiated at 120 kt, 11 kt above the calculated V1. However, due to the light weight the aircraft was within the field length limited performance and stopped safely on the runway.

The debris from the pitot probe was not recovered, so it was not possible to determine the source of the material that obstructed the co-pilot’s pitot probe. Recorded data showed that the calculated airspeed on the co-pilot’s system remained at 0 kt throughout the event and so it is likely that the system was significantly blocked.

The engineering checks carried out on the aircraft before and during the parked period all recorded that pitot covers were fitted. It was not possible to determine when the pitot blockage occurred.