Casualties unknown

2021-09-04: (SE-ROJ) — HR

HR

On September 4, 2021, an aircraft (registration SE-ROJ) was involved in an aviation accident near HR. Investigators recorded the probable cause as: The immediate cause of the accident was an excessive pitch angle around the lateral axis at the moment of touchdown. This summary draws on records from the Air, Maritime and Railway Traffic Accident Investigation Agency of Croatia (AIN).

Sourcesthe Air, Maritime and Railway Traffic Accident Investigation Agency of Croatia (AIN)Primary reportUpdated 1785055897Data APIEditorial standards
Aircraft registered SE-ROJ
Aircraft registered SE-ROJ. Photo: Anna Zvereva / CC BY-SA 2.0, via Wikimedia Commons

An Airbus A320neo experienced a tailstrike during landing at Split Airport due to a significant wind gradient and aircraft pitch dynamics.

What happened

On September 4, 2021, at approximately 10:34 UTC, an Airbus A320neo, registration SE-ROJ, operated by SAS, experienced a tailstrike while landing on runway 05 at Split Airport. The aircraft was on an ILS Z approach, and the crew had been briefed on the potential for a tailwind and the characteristics of the runway touchdown zone.

During the final 70 feet of the approach, the aircraft encountered a significant change in wind direction and speed, specifically a tailwind gradient. As the aircraft descended, the pilot applied a nose-up command at approximately 55 feet. This action, combined with the loss of airspeed caused by the tailwind, led to an increased pitch angle. Just before touchdown, the aircraft's angle of attack reached a level that triggered the high angle of attack protection. This activation of the Flight Control Laws resulted in a further nose-up demand, causing the aircraft's pitch to reach a maximum of +13.4 degrees. Consequently, the lower part of the fuselage near the tail struck the runway surface.

There were no injuries to the 168 passengers or the 6 crew members on board. The aircraft sustained structural damage to the fuselage skin between frames 68 and 72 and longitudinal members 32LH and 32RH, as well as damage to the APU drainage pipe and the rear galley drainage pipe.

The investigation

The investigation, conducted by the Croatian Aviation Safety Agency (AIN), involved analyzing data from the Digital Flight Data Recorder (DFDR) and the Cockpit Voice Recorder (CVR). The analysis was supported by technical reports from the aircraft manufacturer, Airbus, and involved coordination with investigative bodies from France, Sweden, and Norway. The investigation examined the meteorological conditions, the aircraft's flight control laws, and the crew's handling of the aircraft during the final approach phase.

Probable cause

The immediate cause of the accident was an excessive pitch angle around the lateral axis at the moment of touchdown. This was driven by a significant wind gradient and changes in wind speed and direction during the final 70 feet of the approach, which, combined with the aircraft's flight control protections, reduced tail clearance.