What happened
On 5 April 1999, a Bell 206B helicopter, registration G-OPNI, was conducting a private flight from Teignmouth, Devon, to Denham Airport, Middlesex. The pilot intended to follow a direct track of 065° using GPS and visual references. Shortly after takeoff, the aircraft entered a layer of mist, causing the pilot to lose visual references and become disoriented. During an attempt to climb out of the mist, the pilot experienced significant uncontrolled rates of climb and descent.
While flying between cloud layers, the pilot contacted Exeter ATC to request assistance, noting that he was not IMC rated. The controller provided a radar advisory service and suggested headings toward Exeter. However, the pilot, fearing he would have to descend through cloud to reach Exeter, requested a heading toward the coast to descend over the sea. While attempting to descend clear of the coast, the pilot lost control of the aircraft while flying solely by instruments. ATC observed the helicopter turning toward the cliffs of Lyme Bay before radio and radar contact were lost.
The helicopter impacted the sea in a tail-low attitude, subsequently pitching forward and rolling over. Both the pilot and the passenger successfully exited the aircraft through the side doors. Although neither occupant was wearing a lifejacket, the wreckage remained afloat. After approximately 80 minutes in the water, the pair were rescued by a local fishing vessel.
The investigation
The investigation examined the pilot's flight experience, weather conditions, and the sequence of events leading to the loss of control. It was established that the pilot had only completed one flight in the preceding three months, meaning he was not in current practice. While the pilot had received some instrument training via a hood, this was deemed insufficient for managing an unplanned transition to instrument flight under pressure.
Witnesses observed the helicopter flying at low altitudes under cloud cover and noted a steep climb over a caravan site prior to the accident. Furthermore, while the pilot had viewed general television weather forecasts, he had not obtained a specific aviation forecast for the day, which would have indicated a high probability of fog and drizzle along the coast.