A Fokker 50, OO-VLF, is operating a scheduled passenger flight from London City Airport, England to Ronaldsway Airport, Isle of Man. The flight was uneventful and ATC vectors the crew for an ILS approach to Runway 26. The wind was at nearly right angle to the runway, 170º at 25 knots, with gusts up to 34 knots, resulting in a crosswind component.
This resulted in a crosswind component close to the aircraft AOM (Aircraft Operating Manual) of 33 knots.
OO-VLF after the landing on soft ground (source aaib.gov.uk)
At 10.05 local time, the aircraft receives its landing clearance from ATC, with the latest wind, 180º at 24 knots. The Autopilot was subsequently disconnected by the Commander (Pilot Flying). The approach was flown manually with the aircraft at a crab angle of 20º. (The aircraft heading was 245º with the runway centerline heading at 265º, although a 2014 approach chart, see below, states a runway heading of 261º)
IOM Runway 26 Approach chart (© UK-CAA)
At 50 feet AGL (Above Ground Level) the commander started to decrab the aircraft by applying right rudder and into the wind (left) aileron.
At touch down the aircraft heading was 253º and bounced once before touching down again within the Commander applying full right rudder. It became immediately apparent that the aircraft was pulling to the left side of the runway. The rudder input was not enough and the Commander selected full reverse power in an attempt to stop the aircraft from leaving the paved runway surface. It was too late and the aircraft went off the left side of the runways paved surface and came to a stop with the Nose Landing Gear and the Left Main Landing Gear in the grass.
Weights and speeds were consistent with those required in the aircraft performance data for an aircraft in the (flap) configuration, weights and weather conditions.
With the aircraft stopped, the Commander contacted the Senior Cabin Crew Member to find out the situation in the cabin, which was reported as "cabin secure and all unharmed.
The Commander subsequently attempted to taxi the aircraft back onto the paved surface but did not succeed. The aircraft actually turned further to the left as the left main gear would not move. The watch officer from the Airport Fire Brigade noticed the aircraft in trouble and deployed the Fire Brigade to render assistance. ATC was aware of the situation as well and advised the crew to contact the Fire Brigade at 121.6 Mhz who advised the crew to shut the aircraft down. Which the crew complied with. The crew and passengers were then evacuated from the aircraft from the aft righthand door. Several passengers complained afterwards of the height of the exit.
The AAIB investigated the incident and in their report (available by clicking here) concluded that a combination of the following factors were contributing to the occurrence;
Crosswind close to aircraft limit
Crab angle on touchdown (12º left of centerline)
The bounce on touchdown in which the rudder was centred momentarily