Canadian investigators have disclosed that a Boeing 737-700 aborted its take-off roll at low speed after the crew discovered an incorrect flap configuration.
The WestJet aircraft (C-GWJT) had been departing Saskatoon airport's runway 15 for a service to Calgary on 19 April.
Runway 15 is around 6,200ft (1,890m) in length.
Transportation Safety Board of Canada says the crew, having initiated the take-off roll, realised that the flaps had been set to position '1' rather than position '5'.
It states that the aircraft had been conducting a reduced-thrust take-off at a weight of 80.5t (177,600lb). The crew rejected the take-off at 20kt.