Investigators have traced the post-V1 abort of a BMIbaby Boeing 737-300's take-off roll to an oversight which left the stabiliser trim set in the wrong position.
The aircraft, departing Birmingham for Edinburgh in snowy weather on 13 February, failed to rotate at 135kt (250km/h) when the first officer pulled on the control column.
As the aircraft continued to accelerate to 155kt the captain opted to reject the take-off, says the UK's Air Accidents Investigation Branch.
Although the 737 was travelling "well above" the V1 speed of 126kt, the captain correctly judged that the aircraft would be able to stop within the remaining length of Birmingham's 2,600m (8,530ft) runway.
The AAIB found that the crew had omitted to set the stabiliser trim at the usual point because of de-icing procedures under way at the time.
De-icing procedures "disrupted" the crew's routine, it says, leaving the stabiliser trim incorrectly set, and the crew was "distracted" by the unusual requirement to leave the flaps up while taxiing in slush.
The crew also felt pressured by de-icing hold-over time constraints, and the rotation failure "reinforced" the captain's concerns that ice accretion may have affected the aircraft's control surfaces.
"When the first officer said he could not rotate the aircraft, the captain quickly made the decision to reject the take-off, having judged there was sufficient runway remaining to do so and believing the aircraft was not capable of flying," says the AAIB.
While the stabiliser setting was incorrect, it was still within permissible range, so there was no warning horn to alert the crew.
Simulator trials subsequently indicated that the aircraft could have rotated successfully, and climbed away safely, if the crew had applied a "more forceful" pull on the control column.
A Boeing 747-200F operated by US freighter operator Kalitta Air was destroyed at Brussels on 25 May last year when overran during a post-V1 rejected take-off after kestrel ingestion caused its No 3 engine to stall.
Source: Flight International
