A Maine Warden Service plane forced to land on Interstate 95 last spring had a stalled engine, starved of fuel because of a pilot error.

An inspection shortly after the landing by Warden Pilot Daniel Dufault uncovered no discrepancies with the plane, according to an incident report released recently by the Federal Aviation Administration in response to a Freedom of Information Act request filed by the Kennebec Journal.

Additional Photos A Warden Service plane is parked on a ramp of a former highway rest stop on Friday, April 26, along Interstate 95 in Litchfield. Staff photo by Joe Phelan

“There was no mechanical issue with the plane,” Col. Joel Wilkinson of the Warden Service said Friday. “The plane ran out of fuel.”

Immediately after the April incident, officials from the Warden Service said that the plane had an unidentified mechanical problem that forced the landing in the northbound lane of the highway in Litchfield.

Local flight experts said Friday that pilots are required to take off with enough fuel in their tanks that they land with 30 minutes worth left in the tanks — and not to make sure the plane is fueled is inexcusable.

“You plan a flight, you should arrive with 30 minutes of fuel,” said Paul McKeown, chief flight instructor for Maine Instrument Flight at the Augusta State Airport. “If you’re planning on landing with less than 30, that’s a problem.”

Wilkinson would not give specifics about the Warden Service’s investigation into the emergency landing, which led the service to take “corrective action” against Dufault. Wilkinson wouldn’t elaborate on the nature of the action.

Dufault announced on his Facebook page in August that he resigned from the Warden Service.

Wilkinson confirmed Friday that Dufault no longer works for the agency. Dufault could not be reached for comment Friday and has declined to comment since the landing.

No one was injured and the plane wasn’t damaged during the landing, which occurred about 8:50 a.m., Friday, April 26, in the northbound lanes of I-95 near a former rest area at mile 98. The single-propeller plane had taken off from Belfast Municipal Airport on its way to Auburn/Lewiston Municipal Airport.

Dufault was accompanied by Charlie Todd, a biologist with the state Department of Inland Fisheries & Wildlife. They were scheduled to conduct a survey of eagle nests.

The plane, a 1968 Cessna 172 that Dufault helped rebuild a few years ago, remained parked in the rest area parking lot for about two and a half hours before it was refueled and flown to the nearby Augusta airport.

Durward Humphrey, chief pilot for the warden service, said shortly after the landing that the plane had an unidentified mechanical problem that killed its engine power. Humphrey, who flew the plane back to the airport, said it would be inspected to find out what went wrong.

Conflicting reports

A Maine Turnpike Authority traffic alert moments after the landing reported that the plane had been forced down by an empty fuel tank, and Sgt. Jason Luce of the Maine Warden Service also initially said that the plane had “a fuel issue.”

But Humphrey disputed those reports and suggested the plane’s man trouble was mechanical.

The FAA’s initial statement also said the plane had “experienced a mechanical problem.”

Shortly before the plane took off from the highway, wardens directed the news media to the far end of the rest area parking lot before positioning their trucks — and a sport-utility vehicle being used by a film crew for the Animal Planet series “North Woods Law” — in front of the plane, blocking the media’s view.

Wardens still could be seen dumping containers of fuel into the tank spouts atop the plane’s wings. The FAA report says they added about 12 gallons.

“Fuel was a concern,” Humphrey said at the time. “That’s why we added fuel.”

Moments later, Maine State Police troopers closed both of the highway’s northbound lanes. The plane taxied about a quarter-mile south, turned and sped north before lifting off into the clear blue sky and disappearing from view.

Wilkinson said Friday that investigators weren’t sure immediately after the landing whether the plane had a mechanical problem or if it had simply run out of fuel.

“We had no idea why the plane could have landed in that manner,” he said. “To be fair to the employee and the investigation, we had to have (the plane) inspected and interview the employee. The results were that the plane ran out of fuel.”

Humphrey, in his report to the FAA, said Dufault called him shortly after the landing and requested cans of fuel.

“I asked what had happened and he stated he thought he ran out of fuel, but there is fuel showing on the gauges,” Humphrey wrote.

Dufault said he had to yaw the aircraft a couple times to splash enough fuel into the lines to keep the engine running a few seconds longer so he could glide to the Interstate.

“Dufault and I checked the airplane and we inspected the gauges,” Humphrey wrote. “The right gauge indicated on the empty mark and the left gauge was indicating one needle width above the empty mark.”

‘Be skeptical of your gauges’

McKeown said the FAA requires pilots to plan daytime flights under clear conditions, like those on April 26, to end with fuel left in the tank.

Officials said at the time that Dufault was in the air about 35 minutes before running out of fuel about 10 air miles short of the Auburn airport. A typical Cessna 172 has about 38 gallons of usable fuel in a 42-gallon tank and typically gets about 4.7 to 5.5 hours at cruising speeds, according to the Cessna 172 Guide.

“Belfast to Auburn is probably about a 40-minute flight and that plane would use about six gallons of fuel to make that flight,” McKeown said.

Wilkinson wouldn’t say whether Dufault manually checked the fuel level or if he believed he could make the flight from Belfast to Auburn with 30 minutes of fuel to spare.

Sandy Reynolds, fixed-based operator for the Belfast airport and president of Maine Scenic Airways, confirmed that the airport has fueling service and there was nothing to prevent Dufault from adding fuel before taking off.

Reynolds and McKeown agreed that pilots are expected to manually check the fuel level before each flight.

“The airplane fuel tank is made so you can see into it,” McKeown said. “Every pilot is taught to visually confirm the quantity in the tank.”

Dufault believed the plane had fuel because of a gauge that read one needle width above empty. But plane fuel gauges are notoriously inaccurate, McKeown said.

“Every pilot is taught to be skeptical of your gauges,” McKeown said. “All pilots are taught don’t trust the thing unless it says empty.”

Plane gauges are designed to be most accurate when the fuel is nearing the bottom of the tank.

McKeown said a pilot doesn’t want to have an empty tank at the wrong time. “You really need to know when it’s getting down to empty,” McKeown said.

McKeown said fuel level would be a cause for concern well before Dufault’s situation, with one gauge reading empty and another one needle width above empty .

McKeown said the 30 minute minimum required by the FAA should be a worst-case scenario. He requires those in his flight school to plan a trip with at least an hour’s worth of fuel to spare.

“I always point out to people these laws should never be interpreted as being safe,” McKeown said. “They’re saying it’s such a bad idea that we’re drawing a line in the sand. It’s illegal at that point.”

Dufault, who was based at Turner Aviation Field, joined the Warden Service in 2003. A news release at the time said he received his pilot’s license when he was 16 and flew for Currier’s Air Service in Greenville before joining the Warden Service.

Dufault also spent more than four years as a bush pilot, flying for two sporting lodges in Alaska before returning to Maine. He was described by his peers the day of the landing as an outstanding and experienced pilot.

Dufault also is a licensed aviation mechanic who helped rebuild theCessna he was flying on April 26.

McKeown said there is no reasonable excuse for Dufault taking off with so little fuel.

“It happens too often,” he said. “Running out of fuel is preventable and when people do it, it’s usually complacency or wishful thinking or perhaps inattention.”

Wilkinson said the Warden Service requires all pilots to do a pre-flight inspection. He said that policy has been bolstered since Dufault’s landing.

“Just like any policy, it comes down to the employee’s choice to follow that policy,” Wilkinson said.

The FAA said in its report that it was considering a test flight with Dufault to reassess his skills.

McKeown said such a test would be standard after a pilot allows a plane to run out of fuel in flight. It is unclear whether that test ever took place.

An online database shows Dufault is still a certified commercial pilot, but the FAA did not respond to emailed questions seeking additional comment on the incident report and the status of Default’s license.

“It’s fairly easy to not run out of gas in your car,” McKeown said. “The consequences of running out in a plane are obviously different and it’s relatively easy not to do that. You have to pay attention and it’s pretty easy to do that.”

Craig Crosby — 621-5642

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