Accident Details
On 01 July 2002, at 1214 Pacific daylight time, a Cessna 172N, registration C-GRIL, serial number 17268072, took off from Boundary Bay Airport, British Columbia, for a local pleasure flight. The aircraft was rented from Regency Express Flight Operations and carried the pilot and three passengers. During take-off on Runway 25, after the main wheels left the ground, the nose rose to a very steep attitude. The aircraft climbed to an estimated height of 100 to 150 feet, then the right wing dropped, followed by the left, then the right again, and the aircraft struck the runway nose down and right wing low. A fire broke out in the left cowling area, fed by a broken fuel line, but was quickly extinguished by bystanders. Two passengers were fatally injured, the pilot sustained serious injuries, and the third passenger died in hospital the next day. The aircraft was destroyed.
Pilot Information
The pilot held a valid private pilot licence and medical certificate issued by Transport Canada. The licence was endorsed for single-engine land aeroplanes. The medical certificate, requiring glasses while flying, was issued on 13 September 2001, with the last medical on 21 August 2001, valid for 60 months. The pilot had 57 flying hours on light aircraft: 30.7 hours dual and 17 hours solo on the Piper PA-38 Tomahawk, and 7.7 hours dual and 1.6 hours solo on the Cessna 172N. Training was completed with Regency Express between 13 August 2001 and 31 March 2002, mainly on the PA-38. During training, the pilot flew six dual instructional flights on the Cessna 172 and, after licensing, three additional dual and two solo flights on this aircraft. The pilot sustained serious injuries and has no memory of the events on the accident day.
Aircraft Information
The aircraft, manufactured in 1976, had flown 5762.4 hours total since new. The engine, a Lycoming O-320-H2AD, serial number L-3626-76T, had 1575.3 hours total since new. Records indicated the aircraft was certified, equipped, and maintained in accordance with regulations except for two discrepancies: the right-hand fuel gauge was unserviceable and deferred, awaiting parts; pilots were advised to dip the right fuel tank before flight. The aircraft was fuelled to full tanks the previous day. No weight and balance calculation prior to the flight was found. Post-accident calculations using reported occupant weights, full fuel, and no baggage showed a take-off weight of 2589 pounds and centre of gravity at 45.16 inches aft of datum. Maximum allowable take-off weight is 2300 pounds; allowable CG range is 35 to 47.30 inches aft of datum.
Weather
Weather conditions were suitable for visual flight rules. The ATIS message at start-up (valid from 1100 PDT) reported winds 260 degrees magnetic at 10 knots, visibility more than 15 statute miles, broken clouds at 2000 feet, altimeter 30.26 inches, and landing runways 25 and 30. Weather was not considered a factor.
Wreckage Examination
The wreckage was initially examined at the accident site. The aircraft struck the runway nose down on its right side, damaging the right wing and right engine cowling, and forcing the nosewheel up between the pilot's seat and rudder pedals. Both propeller blades were twisted with leading edge damage, consistent with considerable power at impact. The throttle and mixture controls were full forward; the fuel selector was on the left tank. The left fuel line fractured at impact, and very little fuel remained in the left tank; the right tank was full. All control surfaces were accounted for, and damage was attributable to impact and fire, except cuts made by rescue crews. The wreckage was recovered for detailed examination.
Both front seats were locked in the sixth hole from the front. The stall warning horn did not sound when suction was applied to the stall warning hole; examination showed the reed was heavily corroded. A post-production metal flap-position indicator cover limited maximum flap selection to 30 degrees instead of 40. The aircraft records indicated no supplemental type certificate for this modification. Flap position on impact was estimated: from various measurements, the flaps were set between 19 and 23 degrees. The elevator trim tab actuator position corresponded to halfway between neutral (take-off) and full nose-up on the cockpit indicator.
The checklist provided by Regency Express did not include a challenge to verify the elevator trim position before take-off, unlike the manufacturer's pilot operating handbook checklist. The pilot confirmed using the Regency Express checklist.
Investigation Findings
The major element in the accident was the incorrect position of the elevator trim tab, set halfway between neutral and full nose-up, causing a strong nose-up pitching moment at lift-off that led to an aerodynamic stall from which recovery was not possible. A test flight replicating the configuration indicated the required stick force was within a pilot's physical ability, but unexpected, it was unlikely the pilot could react in time. It could not be determined why the trim was not set correctly. The flaps were set inappropriately for take-off (at least 19 degrees, beyond the 10-degree limit), exacerbating the pitch-up. The aircraft was overweight; no weight and balance calculation was likely completed. The stall warning system was defective. The flap selector plate was incorrect for the model. The pilot survived the impact but the passengers did not.