FreezingDrizzle
24th Oct 2018, 09:14
A hair raising moment - total loss of control right after touch down and aquaplaning (in slush) through the landing roll. The CRJ900 came to a halt some 160 meters from the runway end having spun more than 180 degrees.
The local Safety Investigation Authority have now published a report. (I'm not allowed to post an URL but an English version may be found quite easily; Google for example "loss of control at Turku" or check the Safety Investigation Authority Finland web pages.)
In short, the aircraft touched down at 1,95G after which a slight bounce occurred. The impending bounce was just enough for the aircraft to sense an airborne condition. Due to the CRJ900 design logic the reversers were then inhibited as they were selected before the minor bounce. The captain as pilot flying then applied full manual braking but due to over 10mm slush cover (not known or reported to crew) the wheels never started spinning enough for the anti skid to activate. Thus the landing roll from 151 KT to full stop was without reverse and with locked wheels. The first officer applied full braking as well without informing the captain, but as the captain never released the brakes this did not have an effect on the outcome. A mayday call was transmitted during the landing roll.
Astounishingly, the aircraft was able to vacate the runway after a visual check and never exited the runway although at 93 KT it was only some 0,5 m from the unpaved area. A few runway edge lights had to be replaced and the aircraft needed a new set of tyres and some five days for additional checks.
The local Safety Investigation Authority have now published a report. (I'm not allowed to post an URL but an English version may be found quite easily; Google for example "loss of control at Turku" or check the Safety Investigation Authority Finland web pages.)
In short, the aircraft touched down at 1,95G after which a slight bounce occurred. The impending bounce was just enough for the aircraft to sense an airborne condition. Due to the CRJ900 design logic the reversers were then inhibited as they were selected before the minor bounce. The captain as pilot flying then applied full manual braking but due to over 10mm slush cover (not known or reported to crew) the wheels never started spinning enough for the anti skid to activate. Thus the landing roll from 151 KT to full stop was without reverse and with locked wheels. The first officer applied full braking as well without informing the captain, but as the captain never released the brakes this did not have an effect on the outcome. A mayday call was transmitted during the landing roll.
Astounishingly, the aircraft was able to vacate the runway after a visual check and never exited the runway although at 93 KT it was only some 0,5 m from the unpaved area. A few runway edge lights had to be replaced and the aircraft needed a new set of tyres and some five days for additional checks.