Pilots Who Flew ‘The Hump’ Over the Himalayas Have Harrowing Stories to Tell

By Nedda Thomas

Editor’s note: The following is an edited excerpt from Nedda Thomas’ book, “Hump Pilot: Flying Over the Treacherous Himalayas During WWII,” which recounts the wartime exploits of her father, Ned Thomas, a World War II pilot who flew the dangerous route over world’s highest mountain range.

No Hump run over the Himalayas was entirely predictable, but it was always a round trip due to the dearth of fuel in China. Kunming constituted the main Chinese terminus, but Ned Thomas flew into Luliang, Chanyi, Yunnanyi, Li-chiang and other far-flung outposts, landing overburdened planes on primitive airfields and dirt runways that sucked sand into engines and wreaked havoc with the plane’s mechanics.

Of this enormous territory pilots flew, the Himalayas formed the northwestern wall. To the south, the Indian Ocean moated them in. East and nose ahead lay occupied China. Flyers departed India’s Assam Valley, radioed for weather sightings across the Hump from Fort Hertz in Burma and kept flying on a wing and a prayer.

“Turnaround to Kunming,” Ned remembers, “could be eight hours or 10, depending on winds. We were cruising maybe 150 mph, dealing with heavy loads and a lot of resistance. If we were lucky, we had a cockpit heater that worked.”

The aircraft in the foreground is a C-46 transport, originally designed as a commercial plane to carry a crew of five men and thirty-six passengers. The more distant plane is a P-40 fighter, distinguished for its effectiveness in middle-altitude work with the Royal Air Force in England and Africa. | Photo credit Library of Congress

They didn’t always have heaters, but they did have leather jackets layered with extra clothing beneath because cabins turned into flying freezers over the mountains. Ned often waited to turn on his cockpit heater until the return leg with an empty cargo, given the dangers of stray sparks in a plane awash in high-octane fumes and leaks from 55-gallon fuel drums.

“We could take the E-route going out, that’s the lower Hump, maybe flying 16,000 to 18,000 feet,” he said. “The Easy Route reopened with the liberation of Myitkyina (Burma). … Coming back with empty planes, we flew the … route farther north. It’s higher and more difficult. Nowadays planes are pressurized from 7,000 feet. Without pressurization or oxygen, we didn’t customarily take passengers at those altitudes.”

At least the engines had oxygen, thanks to life-giving turbos.

“As you go higher, you have less air and oxygen. … The air gets rarified and engines have to labor harder to operate. … Before turbochargers, as you went higher the engine eventually stalled.

“Then we’d be dropping down through a hole in the clouds to land in China, and most of the light below was from lanterns. Like a scene from the Stone Age.”

The statistics told a terrible story. Half of the Chinese did not survive to age 30. Poverty, disease, brutality and abuse was the status quo. Drought or rainfall determined every harvest, and usually the Japanese were there to pillage first. Bare hands and rudimentary tools scratched subsistence from the soil.

Oxen help load C-46s in Nansin, Burma, in late 1944. | Photo credit National Archives

Flying over scenes that would have looked familiar to Ghengis Khan, Hump planes threaded their course to assorted bases deep in China along a narrow skyway about 50 miles wide that could extend a 1,000 miles in length, depending on the destination.

The Hump was many routes, as it fanned out east of the mountains. Some 13 bases lay on the Indian side, and officially included distant Karachi, a city in modern-day Pakistan. Distances flown could expand or contract in response to the advancing or receding of the Japanese. Flights debarked from India’s soggy Assam Valley and quickly climbed to arctic conditions. At the first major ridge, vegetation thinned away and jagged peaks emerged through the clouds.

According to Lieutenant General William H. Tunner, who commanded the airlift supply operation from India to China, at least 400 Hump planes went down during the 3½-year operation. Somberly, he wrote:

“We had lost planes all through this area, and had never again heard from many of the crews. … Perhaps they had perished in the crash. If they had parachuted out, they may have been caught in the treetops, or injured in the fall to Earth. They could have starved [or] wandered aimlessly in the dense undergrowth until they dropped with exhaustion. They could have been found by native tribes, and been mistreated, murdered or turned over to the Japanese.”

Ned’s ability to focus and compartmentalize wasn’t always easy, but it gave him an edge and he used it. What degree of fear or dread did he experience flying over these jungles?

“I don’t think you dwell on things like that. In the air, you’re intent on monitoring your flight pattern and instruments. …We were all aware of planes being lost over the Hump. For the jungle, we had chits (notes) in local dialects printed on silk so they wouldn’t disintegrate, promising a reward to natives for returning us to a place where we could be rescued.”

Army personnel load a plane with vital military equipment before flying over the Hump in January 1945. | Photo credit National Archives

Embedded deep in this savage terrain of jungles and ridges, several great rivers roared through canyons. On each side of the range, water was obscene and rank, the diseases were exotic and insects and animals stood ready to chomp into a man. In addition, it was not reassuring to see service crews in China routinely siphoning fuel from Hump aircraft before they flew the route back to India. With no allowance made for the unexpected, returns could be cliffhangers for pilots as they watched their fuel gauges tremble.

What about enemy attacks? The Japanese onslaught abated greatly when they were driven farther south into Burma. The real danger they posed sat straight below.

Japan’s foot soldiers spread thick as tar over the terrain, their patrols everywhere, their presence dictating the limited and dangerous air routes planes could fly. With good cause, encounters with them on the ground were more feared than aloft. Pilots often felt they’d rather have taken their chances with Nazi captors than fall to the cruelty of Japanese infantrymen.

But one foe never let up. Killer weather was what enemy pilots faced daily. The best weather—best being in the loosest possible sense of the word—occurs between November and March, before the arrival of the monsoons with their opaque fogs and blinding sheets of rain, which could put runways underwater and periodically shut bases down. From March into summer, the conditions could nix any visibility. It wasn’t unusual for pilots to be unable to distinguish the tips of their wings.

Weather was an everlasting puzzle that constantly tricked American meteorologists on the scene. Reconnaissance, too, was primitive. Most reports relied on pilot debriefings or radio reports along the way. Word of major storms usually arrived too late to be useful, and the rapidly shifting conditions were impossible to anticipate. Tunner said “the weather on the Hump changed from minute to minute, from mile to mile.”

“The wind stream was always precarious,” Ned affirms. “It created updrafts and downdrafts. Those were what was terrible. We were flying a lot of gasoline, one of the worst things you can mess around with. The fumes were all over the plane. You smelled them in the cockpit till you got on your oxygen [mask].”

A frightening mystery rose out of the Hump experience and its weather. Based on accounts of several pilots, a monstrous unnamed summit towered somewhere north of the flight path and crested higher than Mount Everest, 29,029 feet above sea level. Men blown off course by fierce storms found themselves hurled inside a harrowing updraft, and came out at 30,000 feet to confront a giant.

The threatening pinnacle was first sighted by two Chinese National Aviation Corporation (CNAC) pilots as they attempted to map an early route across the range. Later Hump pilots also saw it and gave credible accounts of being flung far too close for comfort.

Did an immense mountain really rise somewhere amid countless others? Were pilots blown there like mariners swept over an unsailed sea, into the unexplored reaches of a remote place? Had their altimeters played them false?

Ned Thomas, who was first in his primary flight class to solo, poses with a PT-17 after completing training at Douglas Army Airfield in Georgia. | Photo credit Photo courtesy of Nedda Thomas

Ned explained the enigma simply in the level-headed terms.

“With different atmospheric conditions, your altimeter will vary as you move from one pressure situation to another,” he said. “You’re always resetting your altimeter on a flight, to reflect these differences. … As you go from one pressure situation to another, ground control will tell you the setting, and you use a knob on the dial to adjust your altimeter. You can get a false altitude reading if you don’t keep changing your setting. Of course, we didn’t have any way to get that information over the Hump because no stations existed in the mountains.”

Plainly put, their altimeters hadn’t malfunctioned, they just weren’t reset for changes in pressure conditions.

Ned’s take on the mystery reflects the knowledge of an instrument pilot, and something of his temperament, too. Things had to make sense. He needed to keep his head and deal with the world he was in. He had cause. They knew about inexperienced flyers sent into the Hump, recent cadets out of flight school, or mature men with minimal training in the instruments needed for high-altitude flying. Some had never flown the C-47 or the bigger C-46.

Deployed as copilots into what was viewed as a backwater war, forgotten while their country pursued a policy of “Europe first,” they took to the highest peaks and worst flying on earth in unfamiliar aircraft, while ground control talked them through basics like adjusting their flaps.

Ned came in with a newer breed that received more training before arriving in theater.

“You had to know the plane you were flying. The history of aviation went back maybe a few decades, but Hump flying was the big unknown. No one ever flew under these conditions. It was a new world.”

—Nedda Thomas is a Virginia-based author and Ned Thomas’ daughter. This story originally appeared in the Fall 2015 issue of On Patrol, the magazine of the USO.

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