Date & Time:
Dec 15, 2022 at 2114 LT
Type of aircraft:
Beechcraft 90 King Air
Operator:
Registration:
N13GZ
Flight Phase:
Flight
Flight Type:
Ambulance
Survivors:
No
Site:
Lake, Sea, Ocean, River
Schedule:
Kahului – Waimea
MSN:
LJ-1590
YOM:
2000
Country:
United States of America
Region:
North America
Crew on board:
1
Crew fatalities:
1
Pax on board:
2
Pax fatalities:
2
Other fatalities:
0
Total fatalities:
3
Captain / Total hours on type:
615
Aircraft flight hours:
10130
Circumstances:
The medical transport flight was en route to pick up a patient on a neighboring island on an instrument flight rules (IFR) flight plan in dark night conditions over the ocean. About 13 minutes after departure, at 13,000 ft mean sea level (msl), the airplane’s vertical gyro failed, which subsequently failed the pilot’s Electric Attitude Director Indicator (EADI), which also caused the autopilot to disconnect. The failure of the EADI and autopilot disconnect required the pilot to manually fly the airplane using the copilot’s attitude gyro for his horizon information (bank angle and pitch attitude) for the duration of the flight. The pilot did not declare an emergency, nor did he inform air traffic control (ATC) that his electric attitude indicator had failed and that his autopilot had disengaged. After the instrumentation failure and autopilot disconnect, the airplane entered a series of right banks before being brought back to level, followed by a left turn, and then subsequent right banks. ATC asked the pilot to change course and the pilot agreed. The copilot attitude indicator indicated that the airplane entered a descending, steep right bank turn. Over the next 5 minutes, ATC issued varying instructions to the pilot. During this time, the airplane entered several right- and left-hand banks and rolls and descended 1,000 ft per minute (fpm), which increased to -3,500 fpm as the airplane’s airspeed increased. About 7 minutes after the instrumentation failure, the airplane was in a 65° bank angle when ATC asked the pilot to verify his heading. As the pilot responded, the airplane bank angle increased to 90° and the airspeed exceeded 260 knots. The bank angle and airspeed continued to increase; a loud metallic bang was recorded that was consistent with an in-flight separation of the empennage from the fuselage before impacting with the water. After an extensive underwater search, the main wreckage was located on the seabed at a depth of about 6,420 ft. The wreckage was recovered and transported to a facility for examination.
Probable cause:
Guardian Flight’s inadequate pilot training and performance tracking, which failed to identify and correct the pilot’s consistent lack of skill, and which resulted in the pilot’s inability to maintain his position inflight using secondary instruments to navigate when the airplane’s electronic attitude direction indicator failed, leading to his spatial disorientation and subsequent loss of control. Contributing to the accident was the lack of a visible horizon during dark night overwater conditions and the pilot’s failure to declare an emergency with air traffic control.
Final Report:
N13GZ.pdf13.93 MB
