The Soviet MiG-15 was designed to intercept enemy bombers at high altitude. With self-sealing fuel tanks and cockpit armor, the MiG was tough and simple, but it had several problems. One 37mm cannon and two 23mm cannons were supposed to shoot down B-29 Superfortresses, but they were less effective in a dogfight with another fighter. While they packed a big punch, cannons fired relatively slowly and the MiG could only carry 11 seconds worth of ammunition; also, the gunsight, leftover from World War II, was designed for lighter .303-caliber shell.
The Soviet jet was powered by a reverse engineered Rolls-Royce Nene, which gave the MiG a thrust-to-weight ratio of 0.60:1 (6,000 pounds of thrust on an aircraft with a loaded weight of 10,000 pounds) which translated into excellent acceleration and climb performance. The wings suffered problems do to poor metallurgical skill and inconsistent manufacturing processes; at higher airspeeds, the wings would actually drop. Even more astonishing, the length of the MiGs wings were not always the same. Finally, the cockpit was cramped and badly organized, with visibility to the rear so bad that a periscope had to be installed.
The MiG-15 was intended as a point defense fighter, which would scramble to intercept enemy bombers, quickly zooming to altitude. If the target was a heavy, not very maneuverable aircraft, one or two passes by the MiG should successfully shoot it down. Air combat is about trade-offs, and the technical aspects of the MiG meant it would be less successful against a light, fast, and very maneuverable aircraft.
Enter the F-86 Sabre. The defining characteristic of the Sabre was a swept wing adapted from the design of the Messerschmitt 262. A swept wing reduces drag at higher speeds because sonic shock waves form at the rear of the airfoil rather than at the front. The drawback is that a swept wing also has a smaller wing area, which translates into a higher wing loading, and a higher stall speed. This, however, is only a problem when a fighter slows down, but slowing down often happens in a swirling dogfight. So the F-86 designers borrowed something else from Messerschmitt, leading edge wing slats such as those on the Bf 109. Running along 75 percent of the Sabre's wingspan, the slats came out when the fighter slowed, thus increasing wing area and lowering the stall speed.
Powered by a J47-GE-13 engine, the F-86 had a thrust-to-weight ratio of 0.45:1, cockpit visibility with its bubble canopy was excellent, and the layout of the controls well designed. Six .50-caliber machine guns had a magazine capacity of 1,800 rounds, and the A1-C ranging gyroscopic sight was highly accurate, when it worked. The gunsight could lock on a target at about 5,000 feet; the pilot would put the pipper on the target, uncage the gyros, and open fire. The gyros and the pipper compensated for g-forces and calculated the lead for deflection shooting. Even when the radar didn't work, the pilot could use Stadiametric ranging by entering the target's wingspan and firing when the opposing aircraft filled his ranging circle.
Air combat is as much about the pilot as it is about his airplane. While the MiG had a performance edge, Sabre pilots were more aggressive and better trained. Many Sabre pilots were retreads, veterans of World War II fighter combat, called up because, ironically, the U.S. armed forces faced an acute pilot shortage following the post-war demobilization. Even the new pilots were well trained, typically entering combat with 350 flight hours. The few Soviet pilots the participated in the Korean War graduated from flight training with about 180 hours. The Chinese, faced with its own shortage of pilots, decreased the training time from 1 year to six months, and pilots graduated with just 60 hours of flight time; ten weeks of conversion training increased the Chinese pilot's hours to 80.
In the skies over Korea, a limited number of exceptionally well-trained, often combat experienced Americans faced off against more, but lesser trained Chinese. The Sabre pilots flew a well-made and well-maintained jet designed to kill other fighters. The F-86 had lighter weapons, better aiming systems, more fuel, and could outfight the MiG-15 below 30,000 feet. The Chinese outnumbered the Americans ten to one, but they were hastily trained and flying a short-range jet that was hard to fly, even though it could outperform the Sabre. The MiG had heavier weapons, but an obsolete aiming system. Finally, the MiG wasn't designed to dogfight, while the Sabre was.
In air combat, many aircraft are claimed to be destroyed by both sides, but often the "destroyed" aircraft manage to survive. MiGs often returned to base with forty or fifty holes, according to one Soviet pilot, even though U.S. intelligence officers often confirmed a kill if the F-86 pilot had managed to score just 13 bullet strikes. On the other side, Chinese often confirmed kills if a radar contact disappeared from the scope, but aircraft would often do that when exiting at low altitude. The best evidence, then, may come from official admissions of aircraft losses, or incontrovertible eyewitness accounts.
F-86 pilots claimed to destroy 800 MiGs. Soviet sources admit to 319 combat shoot-downs, with 309 to Sabres. Chinese sources admit 224 losses, all to Sabres. North Korean sources do not exist, but a defector estimated that at least 100 N.K. MiGs had been shot down, but it might be a good idea to adjust that down to 75 based on possible overestimation. All told, then, 608 MiGs-15s were lost in combat.
The USAF confirms that 78 Sabres were shot down in air-to-air combat. Fourteen more F-86s were lost to battle damage or from running out of fuel, and twelve more are listed as lost to "unknown" causes, making the total of lost Sabres 104. At the same time, however, 47 pilots were killed, 26 were captured, and 65 more were reported as missing in action, for a total of 138. Presumably, if the pilot was lost, then so was his airplane.
A tally of 608 MiGs vs 138 Sabres gives the F-86 a kill ratio of 4.4:1. Air superiority was never in doubt thanks to the F-86.
Source: Hampton, D. (2014). Lords of the Sky: Fighter Pilots and Air Combat from the Red Baron to the F-16. New York: HarperCollins