The Transportation Safety Board of Canada (TSB) has concluded that fuel mismanagement lead to the emergency landing of a small airplane on 36 Street N.E. earlier this year.
The Piper Navajo Chieftain plane was en route from Medicine Hat to Calgary with four passengers and two crew members on board.
The report released Thursday said that just after 5:30 a.m. on April 25, the right engine began to surge 22 kilometres from YYC Calgary International Airport.
When the right engine began surging, the first officer ran an engine failure checklist. The report found the checklist onboard the plane was missing the cause check – which has the crew check items including fuel flow and fuel cell selector position — and feathering of the propeller steps.
The report said the crew requested a runway that was closer to their location and then “lost the right fuel pump.” The left engine began to surge shortly after and minutes later the mayday call went out.
Recognizing they weren’t going to make it to the airport, the crew touched down on the northbound lanes of 36 Street N.E. just north of Marbank Drive N.E. There were no injuries to the passengers, crew or people on the ground.
Fuel on the plane is stored in flexible fuel cells — two in each wing panel: two outboard and two inboard, according to the TSB. The outboard cells, used during flight, each hold 40 U.S. gallons (but had 16 U.S. gallons each at takeoff). The inboard cells, used during takeoff and landing, hold 56 U.S. gallons each.
WATCH: A small plane was forced to make an emergency landing early Wednesday morning, turning a Calgary roadway into a runway. No one was injured. Reid Fiest explains what caused it to happen.
In its report, the TSB said an inspection found there was enough fuel in the plane to make the trip from Medicine Hat to Calgary but the outboard fuel cells of the plane had run empty while the inboard cells were nearly full.
The plane manufacturer’s standard operating procedures (SOPs) states that when fuel management procedures are not in place, fuel starvation can happen even though enough fuel is on board.
The plane’s owner, Super T Aviation, created a SOPs document containing a normal procedures checklist, but there were differences between it and the manufacturer’s pilot’s operating handbook (POH).
The report states that in the POH descent checklist, the crew is told to check the fuel selectors are set to inboard fuel cells. However, the air operator’s normal procedures descent checklist did not include this item. Instead, the step to check that the fuel selectors are set to inboard was included in the before-landing checklist.
Not having switched back to the inboard cells before landing, the crew inadvertently starved the engines of fuel after consuming the outboard cells.
In response, the company has made several changes to its Piper Navajo SOPs, quick reference handbook and normal procedures checklist for the aircraft, and submitted them to Transport Canada. These changes include:
- Step to set a timer when the outboard tanks are selected
- Step to switch from the outboard tanks to the inboard tanks has been moved from the before landing checklist to the descent checklist on the company-generated normal procedures checklist
- Guidance on procedures for accepting runway changes has been added to the company SOPs
- More detail on aircraft evacuation procedures has been added to the SOPs
The report praised the pilots of the plane for their choice of an alternate landing area which led to a successful emergency landing.