Synopsis
On 14 December 2017, an Airbus SE313B Alouette II helicopter, registered TU-HAH and operated by Ivoire Hélicoptère, crashed into houses in the Jean Folly neighborhood of Port Bouët, Abidjan. The aircraft was conducting a technical test flight after a period of inactivity and was equipped with an agricultural spray kit. One person on the ground was fatally injured, the pilot and one other ground person sustained serious injuries, and the mechanic helper on board suffered minor injuries. The helicopter was destroyed.
Sequence of Events
The flight began at 11:27 UTC when the pilot requested engine start for a test flight east of the airport at 500 ft with a planned endurance of 40 minutes. Two persons were on board: the pilot and a mechanic helper. After a long period of inactivity (from 23 February 2017 to 11 December 2017), the helicopter had been modified for agricultural spraying. A previous ground run and check flight on 11 December had been satisfactory.
At approximately 11:31, TU-HAH departed from runway 21 and made a left turn as instructed by the control tower, climbing to 500 ft. The transponder code 1337 was displayed, and the aircraft was visible on radar. The pilot assessed the aircraft parameters as satisfactory and initiated a downwind leg for return. Shortly after, the pilot observed a drop in engine rpm, turned right towards the beach, and then experienced a complete engine stoppage. The helicopter struck electrical wires and impacted houses in autorotation.
At 11:34, the tower repeatedly called TU-HAH for an estimate of point E but received no response. The radar track disappeared on radial 173 at about 2.8 NM from the VOR/DME "AD". At 11:35, the tower received a call from an Ivoire Hélicoptère agent reporting the crash, based on information from the pilot himself.
Injuries and Damage
| Injuries | Crew | Other Passengers | Ground Persons | |----------|------|------------------|----------------| | Fatal | 0 | 0 | 1 | | Serious | 1 | 0 | 1 | | Minor | 0 | 1 | 0 | | Total | 1 | 1 | 2 |
One person on the ground sustained fatal injuries, the pilot and another ground person were seriously injured, and the mechanic helper suffered minor injuries. The helicopter was destroyed. The crash destroyed electrical cables, embedded in the roof of a shop, and damaged a neighboring house.
Investigation Findings
The investigation was conducted by the Bureau des Enquêtes et Analyses des Accidents et Incidents d'Aviation de Côte d'Ivoire (BEA-CI). Examination of the wreckage revealed that the engine failure resulted from a lack of fuel in the main tank. The fuel level indicator was found to have failed, leading to fuel starvation. The aircraft had been inactive for nearly ten months prior to the accident, and its fuel system was inspected only after the accident.
Probable Cause
The accident was caused by an engine failure resulting from a lack of fuel in the main tank, due to a failure of the fuel level indicator.