DH8A, Ottawa Canada, 2003

DH8A, Ottawa Canada, 2003

Summary

On 04 November 2003, the crew of a de Havilland DHC-8-100 which had been de/anti iced detected a pitch control restriction as rotation was attempted during take off from Ottawa and successfully rejected the take off from above V1. The Investigation concluded that the restriction was likely to have been the result of a remnant of clear ice migrating into the gap between one of the elevators and its shroud when the elevator was moved trailing edge up during control checks and observed that detection of such clear ice remnants on a critical surface wet with de-icing fluid was difficult.

Description

On 04 November 2003, a de Havilland DHC-8-100, operated by Air Canada Jazz, was on a scheduled flight from Ottawa/Macdonald-Cartier International Airport, Ontario, to Montréal International Airport (Dorval), Quebec, with 19 passengers and a crew of three. After deicing, the aircraft taxied to Runway 07 and was cleared for take-off. The crew carried out normal pre-take-off checks and commenced the take-off run. On rotation, the pilot felt a restriction to movement of the pitch controls and, as a result, the pilot rejected the take-off.

Upon returning to ramp, the crew moved the elevator controls through their full range of movement and found them free of restriction. The aircraft returned to the gate where maintenance inspected the aircraft and found the controls operating properly and free of restriction. Some freezing rain drops and residual de-icing fluid were found on the horizontal stabilizer and the elevator surfaces, but there were no large pieces of ice. The aircraft was de-iced again and proceeded to Montréal.

The Investigation

The investigation led by TSB Canada concluded that the data, provided by the Flight Data Recorder (FDR), indicated that something had physically interfered with movement of the left elevator -developing an elevator split during the take-off: “At the beginning of the take-off run, both elevators moved in unison to approximately 7.5° trailing edge down at 45 kts indicated airspeed (KIAS). As the aircraft accelerated, a split developed, the left elevator essentially not moving while the right elevator continued to move trailing edge up to a maximum of 2.2° up. The maximum split was 8° at 107 KIAS.”

The full content of this page is available to registered users only.
Please Log in or Register

SKYbrary Partners:

Safety knowledge contributed by: