Wop May, the Mad Trapper of Rat River, and the Arctic Manhunt That Put a Bush Pilot in the Sky Over the Northwest Territories in Nineteen Thirty-Two

In February 1932, a bush pilot named Wop May flew a ski-equipped Bellanca Pacemaker through temperatures of fifty-five degrees below zero Fahrenheit over the Northwest Territories and Yukon, providing aerial surveillance that proved decisive in the most remarkable manhunt in Canadian history. The target was Albert Johnson, known as the Mad Trapper of Rat River - a man who killed an RCMP officer, wounded several more, and evaded trained pursuit teams for 48 days across some of the most hostile terrain on earth. To this day, no one knows who he really was.

Who Was Albert Johnson, the Mad Trapper of Rat River?

Albert Johnson arrived in Aklavik, in the Mackenzie Delta of the Northwest Territories, in the summer of 1931. He paid cash for a canoe, trapping supplies, and food for the winter, and volunteered almost nothing about himself. No one learned his real name, his origin, or what he was running from.

He paddled up the Rat River, built a cabin in the interior, and settled in for a trapping season. That might have ended the story, but local Dene trappers began reporting disturbed traplines - snares sprung with no animal taken, sets moved or stolen. The complaints reached the Royal Canadian Mounted Police detachment in Aklavik.

In December 1931, two officers made the journey up the Rat River to speak with him. Johnson refused to open the door. He stayed completely silent. The officers returned to Aklavik.

What Started the RCMP Manhunt?

The RCMP obtained a warrant and returned on December 31, 1931 - New Year’s Eve - with four officers. The cabin appeared dark and cold, no smoke from the chimney. When Constable Alfred King stepped forward and announced himself, a single rifle shot came through the door and struck him through the chest.

The remaining officers dragged King out of the clearing and ran a 150-mile sprint through Arctic darkness to reach the nursing station in Aklavik. He survived, barely.

The RCMP assembled a nine-man posse and returned on January 9, 1932. What they found made clear Johnson had anticipated exactly this. He had reinforced the log walls of his cabin and dug the floor down nearly two feet, allowing him to fire from just above ground level through carefully cut rifle ports while presenting almost no target to shooters outside. He had turned a trapper’s shack into a fortified position.

The siege lasted fifteen hours in temperatures that dropped to fifty below zero. Officers repeatedly tried to advance and were driven back every time. When they finally brought in dynamite and blew part of the structure apart, there was no body. Johnson had slipped through the perimeter in the night and had been walking for hours before anyone knew he was gone.

The Canadian Broadcasting Corporation picked up the story and broadcast it nationwide. Canadians followed the hunt like a serial drama. Newspapers named him the Mad Trapper of Rat River, and the name never left him.

How Did Albert Johnson Evade the RCMP for 48 Days?

Johnson moved alone through the Arctic in temperatures that regularly reached fifty to sixty below zero Fahrenheit, crossing ground that challenged experienced teams with well-fed dog sleds and full supplies. He laid false trails, doubled back on his own tracks, and walked backward in his own footprints to redirect pursuers. He crossed frozen rivers at unpredictable points to avoid being tracked. In one documented stretch, officers following his trail spent an entire day covering country Johnson had crossed in a few hours.

On February 5, 1932, Johnson shot and killed Constable Edgar Millen in a creek-bed ambush. Millen was an experienced Arctic officer.

With one officer dead, several wounded, and six weeks of pursuit behind them, the RCMP made a call to Edmonton, Alberta.

Who Was Wop May, and Why Did the RCMP Call Him?

Wilfrid Reid May - called Wop since childhood, the result of a younger cousin mispronouncing Wilf, a nickname that followed him without apology for the rest of his life - was not quite forty years old in 1932, and his biography up to that point was almost implausible in its density.

He learned to fly during the First World War and arrived at the Western Front in the spring of 1918. On April 21, 1918, during his very first combat mission, he became the target that Manfred von Richthofen - the Red Baron - chose to pursue. May was a brand-new pilot who had been told not to engage enemy aircraft, had run his guns dry by firing too long, and was in a split-S dive at low altitude with the most feared fighter pilot of the war behind him. Roy Brown, May’s flight leader, dived in from above, and the Red Baron went down on the Australian side of the lines. May landed with a bullet hole in his aircraft. It was his second combat mission.

He returned to Canada after the war with 13 confirmed aerial victories and went back to flying.

By the late 1920s, May was one of the established names in Canadian bush aviation, flying freight, passengers, and mail into country that had no ground transportation at all. In January 1929, he and his partner completed what became one of the famous mercy flights of early Canadian aviation. Diphtheria had broken out near Fort Vermilion in northern Alberta. May wrapped antitoxin in heated blankets to prevent freezing, pre-heated the engine oil before pouring it in, and flew 300 miles north in an open-cockpit aircraft through minus-thirty conditions. The antitoxin worked. The children lived.

When the RCMP asked him to bring his airplane north to help track a man who had been evading pursuit for six weeks, May said yes.

What Was the Bellanca Pacemaker, and How Did It Perform in Arctic Conditions?

The aircraft May flew north was a Bellanca Pacemaker - high wing, radial engine, fitted with skis for winter operations. It was built for load and durability rather than speed, designed to absorb the abuse of working conditions and keep flying when a more refined aircraft would have failed.

Arctic winter flying in a piston single in 1932 demanded constant attention to the oil temperature gauge. Cold attacked oil viscosity and changed the way the engine breathed. Metal components contracted in ways that altered tolerances. A forced landing out there meant a survival situation in terrain that was already trying to kill people who were fully prepared for it. Fuel stops required careful range calculations because the distance between alternatives was not forgiving.

What the airplane gave the RCMP was something entirely new: aerial reconnaissance over wilderness terrain. Johnson’s tracks in the snow were nearly invisible from the ground unless a pursuit team was right on top of them. From altitude on a clear Arctic day, the shadows of disturbed snow created a readable line across the landscape - a man’s path through three feet of powder was visible from a thousand feet up in a way it never was from the surface. May spotted the trail, circled low to mark the direction of travel so dog sled teams below could follow, flew supplies to pursuit teams that had outrun their carrying capacity, and evacuated the wounded.

Why Did Johnson’s Crossing of the Richardson Mountains Stun Experienced Arctic Officers?

Then Johnson did something that challenged belief even among the people chasing him.

He crossed the Richardson Mountains - the range that divides the Northwest Territories from the Yukon - alone, on foot, in February. The passes are brutal terrain in summer. In winter, without equipment support or any possibility of rescue, the Richardsons represent a wall. Johnson went through them.

When RCMP pursuit teams found his tracks coming down the Yukon side, the accounts from those officers document a moment of simple disbelief. They looked at the evidence in the snow and had difficulty accepting what it was telling them.

How the Hunt Ended on the Eagle River

May spotted Johnson on February 17, 1932, moving along the frozen surface of the Eagle River in the Yukon - a solitary figure in a white winter afternoon. May made his pass low enough that the shadow of the Bellanca crossed over him, then banked and circled to bring in the ground teams.

The confrontation was not prolonged. Officers closed in from multiple directions. Johnson turned and fought. He was hit multiple times and kept fighting. He went down on the river ice still shooting, and did not stop until he physically could not.

Forty-eight days after the rifle shot through the cabin door on December 31, 1931, it was over.

Was Albert Johnson’s True Identity Ever Discovered?

A search of Johnson’s pack and pockets produced the supplies of a disciplined wilderness man: Swedish money, gold nuggets, two pistols, a rifle, and enough ammunition to have continued considerably longer than he did. Nothing identified him.

His fingerprints matched no records in Canada or the United States. No missing person report matched his description. The theories accumulated across the following decades - a fugitive from American law, a First World War veteran who had learned survival during the conflict and never fully returned from it, a man who had chosen deliberately and completely to disappear from whatever life preceded his arrival in Aklavik.

Albert Johnson kept the name the newspapers gave him because he never offered another one.

Why This Story Matters in Aviation History

The aerial search for the Mad Trapper was the first time aircraft played a decisive role in a Canadian wilderness manhunt. Before May and the Bellanca Pacemaker, the Canadian North had drawn its own borders with geography and cold. Pursuit over long distances depended entirely on what could move across the surface.

The airplane changed that equation in ways that shaped every search and rescue operation that followed. It could carry supplies to teams that had outrun their sleds’ capacity. It could evacuate the wounded. It could provide real-time aerial tracking with no equivalent on the ground. The technology was rudimentary by any later standard, but the operational principle it demonstrated - that aviation extends the reach of human effort into terrain that otherwise admits no reach at all - has held ever since.

May’s willingness to manage oil temperature in fifty-five-below conditions, making low passes over frozen river valleys with no cockpit heat worth mentioning, was what made the capability real. The airplane was only as useful as the pilot willing to take it where it needed to go.

Key Takeaways

Albert Johnson arrived in the Northwest Territories in summer 1931 and triggered a manhunt when he shot Constable Alfred King through his cabin door on December 31, 1931.
Johnson evaded a full RCMP pursuit for 48 days through temperatures as low as 60 below zero, crossing the Richardson Mountains alone on foot before being cornered on the Eagle River on February 17, 1932.
Wop May - a First World War ace who survived being chased by the Red Baron on April 21, 1918 - flew a ski-equipped Bellanca Pacemaker through the most extreme conditions of the hunt to provide aerial surveillance.
May’s aerial tracking was the first time aircraft played a decisive role in a Canadian wilderness manhunt, demonstrating that aviation could extend the reach of law enforcement and rescue operations into terrain that otherwise drew its own borders.
Albert Johnson’s true identity was never established - his fingerprints matched no records in Canada or the United States, and no missing person report ever matched his description.