What happened
On February 21, 2004, a Schweizer 269 (registration EI-FUN) was engaged in a flight instruction session at Weston Aerodrome. The instructor and student were performing revision exercises to prepare for an upcoming Licensing Standards Test. The specific maneuver being practiced was a "Quick Stop," which involves rapid deceleration to reach a hover.
During the exercise, the student pilot attempted a downwind turn and flare. As the aircraft reached a 90-degree bank, the main rotor blades and the front left skid made contact with the ground. The impact caused the helicopter to cart-wheel for approximately 30 meters before coming to an upright stop. Despite the impact, both occupants evacuated the wreckage without assistance. The instructor sustained minor injuries, while the student was uninjured. The aircraft was subsequently declared beyond economic repair.
The investigation
The AAIU investigation examined the flight dynamics, the environmental conditions, and the suitability of the training area. Investigators noted that the student was operating with a high ground speed of approximately 70-75 knots due to a tailwind. The investigation also reviewed the training syllabus requirements under JAR-FCL, which include performing these maneuvers, and compared them against FAA guidelines, which suggest such high-energy maneuvers are safer when performed into the wind.
Findings
Several contributing factors led to the accident:
- The student pilot applied a back-pressure on the cyclic to initiate the flare while the aircraft was in a steep bank.
- The aircraft was flying at a low altitude, which left the instructor with insufficient time to intervene and recover the aircraft.
- The student pilot experienced discomfort with the high ground speed caused by the tailwind.
- The training area was relatively confined, bordered by a runway to the north and a hedgerow to the south, which may have increased pilot tension.
- The instructor may have allowed the student to maintain control for too long during the critical phase of the maneuver.
Safety action
- The Irish Aviation Authority (IAA) should review the suitability of designated helicopter training areas for performing dynamic, low-level maneuvers at Weston Aerodrome.