What happened
On July 6, 2008, an Aerospatiale AS350B, registration JA9755, operated by Ogawa Air Inc., departed Aomori Airport to perform aerial television coverage of a Japan Maritime Self-Defense Force vessel. The crew consisted of a pilot in command, a second pilot assigned to observation duties, a reporter, and a cameraman.
During the flight, the aircraft traveled along the coast of the Tsugaru Peninsula toward the Shimokita Peninsula. While flying at a low altitude over the sea, the aircraft encountered dense fog. Eyewitnesses reported seeing the helicopter flying near the coast before it disappeared into thick fog, followed shortly by the sound of a crash. The aircraft struck the sea surface near Cape Omasaki and sank. The impact resulted in two fatalities and left two passengers missing. While the airframe was destroyed, no fire occurred upon impact.
The investigation
The JTSB investigation examined the aircraft's flight path via radar records, which showed the helicopter's speed exceeded 100 knots, and analyzed wreckage recovered from a depth of approximately 13 meters. Investigators reviewed meteorological data, including a dense fog advisory that had been issued for the Shimokita area prior to the flight. The investigation also looked into the crew's decision-making process and the company's weather monitoring procedures. Physical examination of the wreckage revealed significant damage to the main rotor hub, blades, and fuselage, consistent with a high-speed impact with the water.
Findings
- The crew likely proceeded into an area where visibility did not meet Visual Flight Rules (VFR) requirements, potentially because the pilot was able to maintain visual contact with the coastline.
- The aircraft entered a region of dense fog where the horizon became obscured.
- The pilot in the left seat likely experienced spatial disorientation after losing the horizon as a reference point, failing to transition to instrument flight techniques quickly enough.
- The aircraft was likely performing a left turn to exit the fog and avoid obstacles, which led to the loss of attitude control and the subsequent high-speed impact with the sea.
- The flight crew and the company's head office failed to sufficiently monitor updated weather advisories regarding the dense fog.