A new report by the Transportation Safety Board of Canada found incorrect fuel and inadequate supervision are to blame for a small plane crash near Thompson that injured eight people last fall.

Keystone Flight 408 left Thompson on Sept. 15 of 2015 en route to Winnipeg, but had problems and turned around.

It crashed about two kilometres from the Thompson Airport around 6:45 p.m., just short of the runway.

Eight people on board were taken to hospital, including six passengers and two pilots.

READ MORE: Small plane crash near Thompson may be result of fuel error

TSB launched an investigation after the crash, and its findings were published Tuesday.

The investigation found the flight was operating a series of trips to several northern Manitoba communities that day. It landed in Oxford House and was scheduled to leave for Pikwitonei Airport, but the crew determined the weather made the trip too dangerous. The crew decided to fly to the Thompson Airport to refuel.

A fuel dealer was contacted to meet the flight, the report said.

The investigation found the pilot-in-command was busy with post-flight duties in the cockpit. The pilot had planned to give the aircraft fuel handling technician the flight’s fuel load information. Instead, the second-in-command pilot took on the duty.

The second-in-command pilot noticed the technician was having trouble finding which fuel filler openings were for the main tank. The second-in-command pilot pointed out the fuel fillers, and asked the technician to fill the main fuel tank and put 80 litres in the auxiliary tank, but did not say what type of fuel was needed.

Neither pilot nor the technician noticed placards or markings on the plane that indicated that the plane required AvGas fuel.

The report said the technician had about one month experience fueling aircrafts and had only just begun to work without supervision.

The technician was required to present a fuel order form where the crew would have specified the fuel type. However, this form was almost never used by the fuel dealer’s employees, the report said.

The technician began fueling the plane after both pilots went into the airport terminal. He was using Jet-A1 fuel in a plane that required AvGas, the investigation found. The spout didn’t fit into the fuel filler opening, the report said, but the technician removed it and installed a reduced-diameter spout.

When re-fueling was finished, the report said the technician printed a fuel slip and wrote that Jet-A1 fuel was used. The technician left the slip in a building where the pilot-in-command couldn’t gain access. As a result, the crew didn’t look over the slip prior to takeoff.

The report said when the crew started the engines, the remainder of the AvGas fuel was still being used by the plane, so the engines were performing normally.

After rotation, the plane wasn’t climbing or accelerating normally, and pressure of both engines started to fall. The pilot-in-command made a radio call to a flight service station saying they needed to return to the runway. However, the engine’s power output kept falling and the plane kept descending.

The report said the plane then tried to perform a forced landing on Highway 391, but oncoming traffic foiled that plan. The plane then made a forced landing in a partially cleared wooded area. The cabin door was forced open during impact with the ground, the investigation found.

The report said those on the plane sustained various serious injuries, but were able to help each other to exit the aircraft. Emergency crews were called.

TSB said a post-accident inspection found safety concerns and Keystone’s air operator certificate was suspended. After an in-depth review of the company’s safety record, the Minister of Transport cancelled its air operator certificate in December of 2015.