Key point: Even low-tech weapons can be effective if used right.

On the night of June 16, 1953, the Associated Press reported on “a boiling mass of flame, mushrooming like an atomic bomb, shoots skyward from a burning fuel dump, set afire at the South Korean port city of Inchon.” The fire “lighted the sky for more than 20 miles” and took three days to put out, having consumed 5.5 million gallons of fuel.

The perpetrators of this devastating attack? A flight of four pokey North Korean two-seat trainers flying blindly through the night.

The Marines, Navy and Air Force fielded their most advanced radar-equipped jet fighters to intercept these low-tech night raiders—but soon also had to contend with deadly MiG-15 jet fighters stalking the night skies over Korea.

Washing Machine Charlie Heckles at Night

The Polikarpov Po-2, or U-2, was a two-seat wood-and-fabric biplane developed in the late 1920s for use as a primary flight trainer. The aircraft’s 125-horsepower Shvetsov engine could lift the plane no higher than ten thousand feet and to a maximum speed of around ninety-five miles per hour. You could outrun one with your typical modern car. Up to five one-hundred-pound bombs could be carried underwing, while backseaters sometimes operated a machine gun on a flexible mount, or hefted mortar shells or bunches of propaganda leaflets to be dropped by hand.

During its darkest hour in World War II, the hard-pressed Soviet air force deployed Po-2 units to harass German troops at night, including the famous all-female 588th “Night Witches” regiment. Though the night raiders inflicted only minor damage, they were devilishly difficult to track and shoot down, and kept troops on the ground stressed and fatigued.

By late 1950, the Korean People’s Air Force had most of its piston-engine fighters and bombers swept from skies or destroyed on the ground by UN fighter planes. While Soviet MiG-15 jets based in China joined the fray in November, it would be a few years before the KPAF’s own MiG-15 pilots were ready for prime time. In the meantime, the KPAF adopted Soviet night-raiding tactics to harass frontline positions, logistical bases and airfields.

The North Korean Po-2s were later joined by around a dozen Yakovlev Yak-18 two-seat basic trainers. A more modern metal-and-fabric design that entered production in 1948, the Yak-18 could fly faster at 150 to 180 miles per hour but had shorter range. Nonetheless, both the Po-2 and Yak-18 could operated from short frontline airstrips at night, and concealed in barns or underground caves during the day.

These “heckling” raids were frequent, scary and noisy—the throaty drone of their motors led to the nickname “Washing Machine Charlie”—but they usually didn’t cause too much damage.

Airbase technician Herbert Rideout recalled that Bedcheck Charlie “would fly over toss out small bombs hoping to hit a tent, aircraft or something else of importance. I found these night time extravaganza’s rather exciting. The sirens would go off, big search lights would come on to try to find him and anti-aircraft batteries would begin firing with tracers which would light up the sky better than any Fourth of July that I had ever seen, and all the time we in trenches were shooting our rifles in all directions. Bed Check Charlie was very elusive and only one was ever brought down.”

But as the 1953 raid on Incheon demonstrated, the night raiders did get lucky sometimes. Late in 1950, two Po-2s hit a line of P-51s at Pyongyang with a cluster of small bombs, damaging eleven and forcing three to be abandoned. Later, two Po-2s ventured over Suwon Air Force Base and managed to destroy an F-86A Sabre of the 335th Fighter Squadron on the runway, and damage eight more of the advanced jets.

Though UN forces disposed of air defense radars, they had only a few squadron of F-82 Twin Mustangs, F4U5N Corsairs and F7F Tigercat fighters designed for night fighting. The Po-2s and Yaks flew low and slow, and were not highly visible on radar due to their small size and fabric construction.

Still, Marine fighter pilots did make a few successful intercepts. Benefitting from onboard radars, twin piston-engine Tigercats shot down two Po-2s, while gull-winged F4U-5N Corsair, arguably the best naval fighter of World War II, also scored several kills. Corsair pilot Guy Bordelon would shoot down three La-11 fighters and two Yak-18s at night over Korea, becoming the only Navy ace of the Korean War.

Skyknight and Starfire to the Rescue

In December 1951, a flight of MiG-15s buzzed the South Korean capital of Seoul at night, startling the U.S. military with the realization they had no night fighters jets that could meet the Soviet jets on equal terms. All three branches of the U.S. military hastily deployed their most advanced radar-equipped jets to counter the threat.

For the Air Force, this meant transferring F-94B Starfire jets of the 319th Fighter Squadron to Korea. The two-seater straight-winged jets were derived from the P-80 Shooting Star, the first operational jet fighter of the U.S. Air Force. The F-94 had first been developed in 1949 to counter the Soviet Tu-4 strategic bomber, a reverse-engineered B-29. The Starfire’s nose-mounted APG-33 radar helped it home in on enemy aircraft at short range, but it still required ground controllers with longer-range radars to direct it in the general direction of the enemy. An uprated J-33 turbojet compensated for the weight of the radar and radar operator, and even featured the first functional afterburner on a U.S. military aircraft.

However, the Starfire’s gear was still considered so advanced in 1951 that it was initially forbidden from flying over North Korean territory for fear that crashed aircraft would offer a technological bounty to the Soviets.

But while hunting night intruders, the Starfires were so fast that they closed too rapidly and often made repeated passes, unsuccessfully attempting to line up the propeller planes in their gunsights. The commander of the 319th perished when he fell below his Starfire’s stall speed of 110 miles per hour while attempting to slow down enough to fall in behind a Po-2—a circumstance some consider the only biplane-on-jet “maneuver kill” in history. Another F-94 crew reported “splashing” an intruder and then was never heard from again, possibly having collided with the wreckage of their victim.

Larger F3D Skyknight jets of the Marine Corps and Navy were more successful over the night skies of Korea. Designed by legendary aviation engineer Ed Heinemann, who created the A-4 Skyhawk, the chunky Skyknight was nicknamed “Willy the Whale” due to its capacious fuselage, necessitated to accommodate both the extra large thirty-inch radar antenna in the nose, and its operator, seated beside the pilot.

The F3D’s AN/APQ-35 radar was more effective than the F-94’s, because it actually compromised three radars employing more than three hundred vacuum tubes: both a long-range search radar and a short-range tracking-and-targeting radar in the nose, plus a third rear-facing threat-warning radar to detect approaching attackers. The APQ-35 could detect fighter-size targets over twenty-five miles away, which made the Skyknight more effective as a patrol plane—and its four twenty-millimeter cannons packed a heavier punch.

Though the Skyknight had arrester hooks and folding wings for carrier operations, they were mostly flown from bases on land; their sensitive equipment was easily banged up by carrier landings, while their powerful, downward-canted engines were known to set decks on fire if left idling too long.

Therefore, the Marines’ “Flying Nightmares” squadron VMF-513(N), flying from land, was the first to use the type in action from a base in Suwon. They were later joined there by the Navy’s VC-4 “Night Capper” squadron, detached from the carrier USS Lake Champlain.

With a maximum speed of 565 miles per hour, the clunky F3D-2 was over a hundred miles per hour slower than the MiG-15, and no match in a conventional dogfight. But the F3D’s radar allowed its crew to “see” its opponents better at night, while the MiGs relied on their ground-based radars to direct them.

On November 8, 1952, the F3D flown by Oliver Davis and Dramus Fessler were directed towards a MiG-15 flying ten miles ahead of them at seven thousand feet. Fessler was able to track the MiG’s position on his radar until Davis spotted the bloom from the MiG’s turbojet engine and fired a burst from his twenty-millimeter cannons. Lt. Ivan Kovalev successfully ejected from the Soviet fighter after it burst into flames.

Five days earlier, Major Stratton claimed to have shot down a Yak-15 in his Skynight—though, as the type was never operated over Korea, it’s not clear what exactly he engaged.

In another unusual engagement, Lt. Joseph Corvi and Sgt. Dan George tracked a Po-2 biplane over Sinanju on December 12, 1952. Unable to spot the tiny biplane far ahead, Corvi aimed a burst of his cannons purely based on the radar contact, and scored the first beyond-visual-range kill in air-combat history.

The MiGs Strike Back

U.S. jets weren’t the only ones making night interceptions. American B-29 strategic bombers had been forced to fly by night because of their excessive vulnerability to MiG-15s. As Soviet La-11 night fighters lacked the speed and climb rate to intercept them, the VVS deployed MiG-15s to attempt intercepts at night under the direction of ground controllers.