What happened
On 13 September 1998, a Sikorsky S76A (Modified), registration G-BVKR, was performing an oil exploration and production support flight. The aircraft was en route to North Denes, Norfolk, after having de-manned an offshore platform. During the flight, the co-pilot reported hearing an unusual external noise, though the commander could not detect it.
As the helicopter approached North Denes on short finals, the Air Traffic Controller alerted the crew that an object appeared to be hanging from the rear of the aircraft. The crew performed a hover taxi to the dispersal area and shut down the engines without further incident. Upon inspection, no object was found attached to the aircraft, but the horizontal stabiliser showed several punctures. An aircraft cargo strop was later recovered from the runway.
The investigation
The investigation established that the incident was caused by the inadvertent dislodgement of a cargo strap from the baggage compartment. This occurred while the helicopter was boarding passengers at an unmanned offshore platform without the assistance of a Helicopter Landing Officer. The strap had fallen onto the landing gear door and became trapped when the landing gear was retracted. During flight, the strap flailed, leading to the noise heard by the co-pilot and the resulting damage to the horizontal stabiliser.