What happened
On March 20, 2022, a Cessna 172P, registration N98763, was destroyed during a routine hurricane and tsunami practice flight near Kekaha, Hawaii. The flight, operated by the Civil Air Patrol under Part 91 regulations, departed from Lihue Airport. The intended flight path involved flying inland, passing a radar dome at Barking Sands PMRF, and then turning west to follow the coastline at 1,000 feet above ground level.
According to ADS-B data, the aircraft did not execute the planned turn toward the coast. Instead, it continued over land and ascended a ridgeline until it impacted a near-vertical mountainside at approximately 3,600 feet. The impact occurred in a nose-up, wings-level attitude. The two pilots on board sustained 2 fatal injuries.
Witnesses at the Kalalau lookout reported hearing the aircraft but could not see it due to heavy fog, with visibility reported as low as 20 feet. A nearby helicopter pilot observed the aircraft flying straight and level before it entered a cloud layer. Following the crash, a search and rescue helicopter located the fragmented wreckage in steep, mountainous terrain.
The investigation
Post-accident examination of the wreckage confirmed that all primary flight control surfaces, including flaps and trim tabs, were intact and functional. The engine showed damage consistent with the impact and the subsequent fall down the mountain, though some engine components were not recovered. The propeller exhibited impact damage and rotational scoring on both blades.
Toxicology analysis of the pilot's liver and muscle tissue revealed the presence of gabapentin. While this medication can cause side effects such as dizziness or drowsiness, investigators determined it was unlikely to have contributed to the accident, noting that the co-pilot could have mitigated any impaired decision-making.
Findings
- The aircraft impacted the terrain in a controlled manner while flying in IMC (instrument meteorological conditions).
- The pilot failed to follow the planned flight route, which would have moved the aircraft away from the rising terrain.
- Poor visibility and low clouds obscured the mountainside during the flight.