What happened
On the night of 7 September 2023, a Bell 212 helicopter, registration A6-ALD, was performing a non-revenue training flight from Al Maktoum International Airport toward the ARAS Driller Rig located offshore Umm Al Quwain. The crew consisted of an instructor pilot and a pilot undergoing route familiarization for the specific location.
During the third circuit at the offshore helideck, the aircraft entered a rapid descent. The helicopter impacted the water approximately 600 meters northwest of the drilling rig. The impact resulted in the destruction of the aircraft and two fatal injuries to the crew.
The investigation
The GCAA AAIS investigation examined the aircraft's mechanical condition and the flight's operational context. Technical analysis of the engines and the main rotor transmission confirmed that the aircraft was airworthy prior to the accident. Data from the engines showed that both power plants were delivering high power and maintaining normal rotor speed until the moment of impact. There were no mechanical defects or pre-existing fractures found in the mast assembly or driveshaft.
Investigators also reviewed the crew's duty records and the operator's training protocols. The investigation noted that the instructor's flight duty period had exceeded the maximum limits allowed under regulations, and the pilot in the right seat was experiencing the night offshore environment at this location for the first time.
Findings
- The primary cause of the accident was spatial disorientation caused by a lack of external visual references during the night flight.
- This disorientation led to a loss of situational awareness, preventing the crew from maintaining a proper aircraft attitude or executing a level-off maneuver.
- The instructor pilot was not adequately rested, having exceeded prescribed duty time limits.
- The crew composition involved a pilot performing route familiarization in a high-risk, low-visibility environment.
- The takeoff for the third circuit was not performed in accordance with operational manuals regarding heading selection to maintain the rig as a reference.
Safety action
Following the investigation, safety recommendations were issued to Aerogulf Services to improve flight training and operational oversight for high-risk missions. The recommendations include enhancing scenario-based training for night offshore operations and strengthening fatigue risk management and crew pairing policies to ensure pilots are sufficiently rested for complex night missions.