The DC two and a half and the impossible ferry flight out of China

In the summer of 1941, mechanics in wartime China bolted a Douglas DC-2 wing onto a damaged Douglas DC-3 and successfully ferried the crippled airliner out of contested territory. The resulting aircraft, nicknamed the “DC-2½,” flew roughly three hours to Hong Kong with a right wing five feet shorter than its left. It remains one of aviation’s most remarkable field-repair stories.

What Was the DC-2½?

The DC-2½ was a Douglas DC-3 airliner operated by the China National Aviation Corporation (CNAC), tail number NC25691, that had its destroyed right wing replaced with a spare DC-2 wing in a field repair. Because the DC-2 wing was roughly five feet shorter than the DC-3 wing and used a different airfoil, the resulting aircraft was visibly asymmetric.

The nickname stuck because the airplane was, mechanically speaking, halfway between the two Douglas types. One wing said DC-3. The other said DC-2. Together, they made a DC-2½.

How Did a DC-3 End Up With a DC-2 Wing?

CNAC was a joint venture between Pan American Airways and the Chinese government, flying mail, cargo, officials, and silver bullion between Hong Kong and the free Chinese interior. By 1941, Japanese fighters routinely hunted CNAC aircraft on the ground and in the air.

NC25691 was sitting on the ramp at Suifu, in Sichuan province, when Japanese fighters strafed her. Machine-gun fire chewed through the main spar of the right wing, and the outer panel came apart. The airplane was upright but unflyable, and stranded on a dirt strip deep in contested territory.

Ordering a replacement DC-3 wing from the Douglas plant in Santa Monica, California meant shipping it around the Cape, up through India, and over the mountains — a process measured in months. Leaving the aircraft where it sat was a gift to the next Japanese bombing run.

Who Engineered the Repair?

CNAC’s chief mechanic, a Polish-born engineer named Zygmund Soldinski, cabled Hong Kong with a proposal: bolt a spare DC-2 wing onto the damaged DC-3. Hong Kong cabled back a single word — “Permission.”

The two airplanes were related, but not the same. The DC-2, introduced in 1934, carried 14 passengers on two Wright Cyclone engines. The DC-3 was a stretched, widened, aerodynamically refined successor carrying 21 passengers on a larger wing with bigger engines. The airfoil, root attachment, dihedral, control cable runs, and aileron size were all different.

Soldinski and his Chinese mechanics had to:

Modify the wing root to mate two different structural interfaces
Fabricate adapter plates from whatever steel was available
Re-route the control cables so the smaller DC-2 aileron would respond to the DC-3 cockpit controls
Work under tarps by day to hide from reconnaissance and by lantern light at night

Depending on the account, the repair took somewhere between three and six days.

Who Flew the DC-2½ Out?

The volunteer pilot was Captain Harold “Hal” Sweet, an American former military pilot and veteran CNAC captain. Sweet inspected the bolted-on wing root, climbed down, and agreed to attempt the ferry flight.

The asymmetric wing produced asymmetric lift. As soon as speed built on the takeoff roll, the airplane wanted to roll hard right. Sweet flew the entire leg with full left aileron and full left rudder, both feet on the rudder pedal, the yoke cranked all the way over. She was still trying to roll.

But she flew — wobbly, crabbed, and about 20 knots slower than a normal DC-3.

Sweet hand-flew the airplane through mountain passes for roughly three hours, without autopilot or copilot assistance, and landed safely at Kai Tak Airport in Hong Kong. Mechanics there removed the DC-2 wing, fitted the proper DC-3 replacement that had finally arrived from the States, and returned the airliner to revenue service, where she flew the rest of the war.

Why This Story Matters

The DC-2½ is more than a mechanical curiosity. It’s a reference point for a vanished era of aviation problem-solving — when mechanics and pilots in the field made decisions that today would require engineering review boards, airworthiness directives, and months of analysis.

Modern regulation exists for good reasons. The FAA framework grew out of exactly the kind of improvisation that occasionally killed people. But the DC-2½ represents a faith — in hand tools, in training, in the people on the ramp — that produced a working airplane on a dirt strip in the Chinese interior when the alternative was losing it to the enemy.

What Happened Afterward?

The aircraft returned to service with CNAC and survived the war, though records differ on the exact retirement date.
Captain Hal Sweet continued flying the Hump route for CNAC and later the Air Transport Command, accumulated thousands of hours over the Himalayas, survived the war, and returned to California.
Zygmund Soldinski stayed in aviation, joined Pan American after the war, and died in the 1970s, largely unrecognized outside the CNAC community.

Photographs of the mismatched aircraft do exist and are accessible online. The definitive written account appears in Gregory Crouch’s book China’s Wings, along with records preserved by the CNAC alumni association and the Pan American archives at the University of Miami.

Key Takeaways

The DC-2½ was a Douglas DC-3 (NC25691) flown out of Suifu, China in 1941 with a DC-2 wing bolted to its fuselage after a Japanese strafing attack.
The right wing was approximately five feet shorter than the left, with a different airfoil, dihedral, and aileron size.
Chief mechanic Zygmund Soldinski led the field repair; Captain Hal Sweet volunteered for the ferry flight to Hong Kong’s Kai Tak Airport.
The aircraft required full left aileron and full left rudder throughout a roughly three-hour flight and cruised about 20 knots slower than a standard DC-3.
The airplane was repaired with a proper DC-3 wing in Hong Kong and returned to revenue service for the remainder of the war.