Scheduled Revenue Flight

In poor weather conditions, the crew continued the approach below the minimum safe altitude until the aircraft impacted terrain short of runway threshold. The lack of visibility caused by the heavy rain falls remains a contributing factor, but the crew should have made the decision to initiate a go-around procedure since the landing was obviously missed.

Failure of the left engine shortly after takeoff due to fuel exhaustion. It was reported that the fuel tank connected to the engine was empty at the time of the accident and that the pilot already completed other flights during the day between Karimui and Kundiawa and back without adding fuel.

Loss of control during takeoff after the aircraft suffered aquaplaning

An investigation conducted by the Australian Transport Safety Bureau (ATSB) revealed that an explosion and fire occurred shortly after takeoff, causing the electrical system to fail. The fire's source probably was the terminal board between the inverters and a control relay. Kerosene carried in passenger luggage in the Twin Otter's aft cargo hold possibly began leaking and was possibly ignited by faulty or age-deteriorated electrical wiring.

Controlled flight into terrain.

It was determined that the accident was the consequence of the following factors:
- Poor quality in the organization of the meteorological support at Lagos airport, as a result of which the crew did not receive reliable information about the actual direction and force of the wind during the approach and landing procedure, which caused the aircraft to land too far down the runway;
- The presence of a layer of water on the runway, about which the crew was not informed prior to landing, which caused the aircraft to enter an aquaplaning mode and the loss of braking action efficiency;
- The failure of the crew to initiate a go-around procedure after he encountered poor weather conditions during the final stage of the approach and an erroneous estimation of the actual remaining length of the runway for the safe completion of the landing in case of heavy rainfall;
- Violation on part of the cabin crew requirements for the number and placement of flight attendants at landing, which led to unnoticed penetration of 15 passengers into the rear trunk and toilets after the plane crashed and their death in the event of a fire;
- Unsatisfactory organization of rescue operations at Lagos Airport.

It was determined that the accident was the consequence of a controlled flight into terrain. The following contributing factors were reported:
- The crew continued the flight at the altitude of 400 metres while the minimum safe altitude for the area was fixed at 800 metres,
- Poor visibility due to low clouds (600 to 1,500 metres),
- The crew failed to return to the departure point when weather conditions deteriorated,
- Loss of visual contact with the ground after the crew decided to continue under VFR in IMC conditions,
- The crew did not receive the emergency radio station and signal devices before departure, as well as the fact that on that day the dispatch microphone at the Kherpuchi Airport was not turned on, which made it impossible to establish the actual instructions of the flight director. In such conditions, the flight was not monitored.

The crew failed to follow the approach checklist and failed to lower the landing gear.