Archive for July, 2010


July 14, 2010


July 14, 2010

The Mikoyan-Gurevich MiG-15 (Russian: Микоян и Гуревич МиГ-15) was a jet fighter developed for the USSR by Artem Mikoyan and Mikhail Gurevich. The MiG-15 was one of the first successful swept-wing jet fighters, and it achieved fame in the skies over Korea, where early in the war, it outclassed all enemy fighters. The MiG-15 also served as the starting point for development of the more advanced MiG-17 which would oppose American fighters over Vietnam in the 1960s. The MiG-15 is believed to have been one of the most numerous jet aircraft ever made, with over 12,000 built. Licensed foreign production perhaps raised the total to over 18,000.The Mig-15 is often mentioned along with the F-86 Sabre in lists of the best fighter aircraft of the Korean War and in comparison with fighters of other eras.
On November 30, 1950, at 0720 hours (local) during a raid on the North Korean Air Base at Namsi, an American B-29 Superfortress was hit by cannon fire from an aircraft that flashed by so fast, the gunners had no chance to return fire. Luckily the damage was confined to the outer port wing of the Superfortress and it immediately turned back toward its base. F-80C “Shooting Stars” which were escorting the B-29’s tried to engage the interloper but were left in the dust as the stranger turned northeast toward the Yalu River. The Americans had not even had time to identify the nationality of the craft, and though a couple of F-80 pilots got a fleeting glance at the silhouette, intelligence officers at the debriefing were unable to identify the craft except to say it was jet powered. F-80 pilots estimated the craft was approximately 85 mph (136.8 kph) faster than the Shooting Star. Damage to the B-29 indicated the craft carried at least one 37mm cannon and probably another, smaller cannon. This was the debut of the “MiG-15” and USAF brass viewed the development with what was described as “organized panic”, from Korea all the way to the Pentagon.

In 1939, Anushavan Ivanovich (“Artyom”) Mikoyan and Mikhail Iosifovich Gurevich teamed up to enter a design competition for a new Russian monoplane fighter. They won the competition and their outstanding MiG-1 design was put into production by the TsKB (Central Constructor Bureau) and the Mikoyan-Gurevich Design Bureau was formally recognized by the Soviet government in early 1941.

The close of WWII found Russia with an abundance of captured German aircraft technology. There were experiments in high speed and near sonic speed flight, which the German scientists were unable to put to practical use due to allied bombing and the subsequent deterioration of facilities. There were captured Messerschmitt Me-262 and Arado Ar.234 jet aircraft along with many brand new Jumo and BMW jet engines, still in crates. Everything including scientists, experimental data, engines, aircraft, tools and machinery was immediately confiscated, loaded into boxcars and shipped to Russia. This action put the Mikoyan-Gurevich Design Bureau in possession of mounds of secret German documents and the scientists who had created them.
The introduction of the MiG-15 was a total (nasty) surprise to the NATO air groups, somewhat comparable to the surprise the Allies received when the Japanese A6M Zero-Sen made its appearance a few years before, during WWII. The Mig-15 was developed under the utmost security. The Soviet philosophy was; if another country could achieve military superiority, sooner or later it was bound attack Russia, just as the Nazis had on June 22, 1941. Under Stalin, military weapons research had high priority and the secrecy involved was deadly serious. Anyone even suspected of the slightest security violation was tortured and executed. The KGB was listening. Thus, the MiG-15 – arguably the worlds best fighter aircraft at the time – was produced in near total secrecy.

The first step toward producing the first MiG jet was known as the model I-250. It featured the odd installation of a 1,400 hp (1045 kW) piston engine in the front and a small, 650 pound static thrust (2.89 kN) jet located in the rear. The craft itself was vaguely reminiscent of the sleek MiG-1 with a rather sharp nose, and cockpit set into the back half of a bullet-shaped fuselage. It was said this oddball craft had a top speed of well over 500 miles per hour (805 kph) in level flight, placing it in the elite group of the fastest prop driven planes in the world.

Though the goal was to produce a pure jet aircraft, Russia simply did not have the engineering expertise to build a jet engine capable of enough power to better the speed of a prop driven plane. Like the US a few years before, the Soviets in 1944 were working with technology acquired from building turbochargers for piston engines. It is (very roughly) a similar problem designing a jet engine as designing a turbocharger; extremely hot exhaust gases under pressure are used to power a turbine. In front of this turbine (connected the same shaft) is a compressor which packs fresh air and fuel into a combustion chamber. Upon ignition, the hot gasses are produced which power the turbine, thus producing a self sustaining reaction and (in the case of the jet engine) the thrust needed to power the aircraft. The first practical Soviet jet powered aircraft was the Mig-9 which flew on April 9, 1946. It had a top speed of 560 mph (901.23 kph) which was much faster than the prop driven aircraft of the time, but not faster than the American P-80A Shooting Star (the designation “P” for “Pursuit” was changed in 1948 to “F” for “Fighter”).
While the Soviets were having their developmental problems, the British on the other hand seemed to be years ahead of everyone. The Jumo and BMW engines the Russians had captured in Germany were rather primitive when compared to England’s Rolls-Royce jet engines in the late part of 1945. And just as it appeared the rest of the world was about to leave the Soviets far behind in the race for a more practical jet engine, fortune truly smiled on the Reds.

In Britain, Clement R. Attlee of the socialist Labor Party was elected Prime Minister in 1945. Attlee, being somewhat naive about the Russian brand of socialism, immediately set about improving relations between Britain and Russia. At the invitation of Attlee, Joseph Stalin sent a team of scientists and engineers to the Rolls-Royce factory to study the design of the superb “Nene” jet engine. Arrangements were made for the Soviets to manufacture the engine in Russia under license from Rolls-Royce. They also took several Nenes with them when they returned to Russia. The Russians wasted little time in copying every detail of the engine and appropriating the design as their own, calling it the “Klimov RD-45” with no regard at all being given to the licensing agreement with Rolls-Royce. However, due to the quality of the Russian materials used in construction of the RD-45, performance of the engine left much to be desired. Turbine blade failures were common, and average time between overhauls was on the order of a very few hours. Fuel consumption bordered on the intolerable. The dogmatic approach of the Soviet aircraft industry solved these problems one-by-one and eventually produced an engine of nearly equal quality to the original Nene. It was called the Klimov VK-1 – still almost an exact copy of the Nene.
Now in possession of a powerful and reliable jet engine, work was resumed on the design of a suitable airframe. The “I-310”, as the super secret Mikoyan-Gurevich craft became known, was first flown in late 1947 and it was immediately obvious to the Russians that they had a “world beater” on their hands. There were still some flaws to be eliminated, but it possessed dazzling performance.

Throughout the late forties, development proceeded on the I-310. Different combinations of cannon were tried, The final arrangement being two 23mm NK23 cannon slung under the left side of the nose and a 37mm NS37 under the right, with 80 rounds for each of the 23mm and 40 rounds for the 37mm. This assemblage provided a devastating punch for the little fighter, although not without compromise. The rate of fire was very slow when compared to the US .50 caliber (12.7mm) machine gun. The target was harder to hit, but it took only 1 round from the 37mm or between 2 and 3 rounds from the 23mm to destroy an enemy fighter.

It was found the aircraft had an alarming yaw at speeds above Mach 0.9 and it also had a tendency to flip itself out of a high speed turn. This latter problem was common to most early, high speed jet fighters. The yaw problem was never satisfactorily resolved. The craft was simply fitted with speed brakes on each side of the rear fuselage which automatically opened at Mach 0.9. The Soviets were fond of simple, crude fixes such as the speed brakes. When it was found that production standards were being ignored and a resulting problem of unequal lift from the wings occurred, the Russians simply improvised a trim tab to one of the wings to increase or decrease the lift of that wing. However, the trim tab could only be adjusted while the craft was on the ground..

Though engine problems, airframe problems and even weapons problems continued, the craft was rushed into production . The first production MiG-15 flew on the last day of December 1948. Continuous improvements were made and in early 1950, the MiG-15bis debuted. By this time, most of the problems with the engine and flight characteristics were alleviated (though “flicking” out of tight turns would dog the fighter throughout its life). With the Klimov VK-1 engine, fuel consumption was still somewhat of a problem but external fuel tanks gave the “bis” an acceptable combat range. Later, the production MiG-15bis would be fitted with an improved Klimov which somewhat alleviated the fuel consumption problem.

The MiG-15bis would go on to equip almost every communist nation in the world, and was manufactured in many. It was also sold to quite a few non-communists. Most of the countries of Africa bought them as well as most middle eastern countries and countries which were not members of NATO.

Included amongst the communist states equipped with the MiG-15bis was North Korea and China. By the time the Korean War began on June 25, 1950, Chinese pilots (some of which were veterans of WWII) had been quickly trained in the bis and on November 26, 1950, when Mao Zedong (Mao Tse-tung ) sent ground troops to assist the beleaguered North Korean army he also sent the MiG-15bis and its trained pilots.

The later production MiG-15bis was powered by a Klimov VK-1A engine with a static thrust of 5,900 pounds (26.24 kN) and the speed was 668 mph (1075.04 kph). It had the same armament of a 37mm cannon and dual 23mm cannon but contained in a unique removable pod. This gun-pack was drawn up into the fuselage by means of a cable winch located just behind the nose wheel compartment. The 37mm NS-37 Nudelman-Suranov cannon was on the right side of the nose wheel and the NK-23s (the later production dash 15bis had NS-23s with a faster rate of fire) were on the left. The use of spare gun-packs meant the turn-around time between sorties was very short.

As experience revealed, having the best military tools and winning the battle do not necessarily go hand-in-hand. In the case of the MiG-15 a superb fighter aircraft was flown by pilots who had received inferior training. Unlike their US counterparts, Chinese pilots of WWII were not taken out of combat and used to train new pilots. Thus, the skill level of the Chinese pilots on average was far below that of the UN pilots. This was very apparent in the US vs. Chinese kill ratio of better than 8:1 during the Korean War. And this was done with the slightly inferior F-86 which had neither the speed, maneuverability nor the altitude of the MiG. The difference was the higher quality training received by the American pilots and NATO pilots in general.

So many variants and sub-variants of the MiG-15 were produced that it would take a very heavy book to list them all. The Soviets were very fond of modifying this aircraft to fit every task from target towing to night fighter interception and ground support . However, the most important variant was the MiG-15UTI which was a two seat (tandem) model used for training new pilots. The MiG-15UTI was produced in greater numbers than the bis and was still in use in the late 1980s by communist and non-communist countries around the world.

The Mikoyan Design Bureau continues to produce aircraft of outstanding performance including the MiG-29 “Fulcrum”. In the right hands, the Fulcrum is more than a match for any aircraft in the world.

Role—- Fighter
Manufacturer—- Mikoyan-Gurevich
First flight——- 30 December 1947
Introduced—— 1947
Primary users—-Soviet Air Force
PLA Air Force
North Korean Air Force
41 others
Number built—12,000 +
Variants ——— MiG-17

MiG 15

July 7, 2010

Apart from various aerodynamic advantages, the MiG-15 was also much more heavily armed than the Sabre which, like the Shooting Star, was equipped with six 50 caliber machine guns. In contrast, both the British and the Soviets had learned during the previous war that cannon fire was much more effective than machine guns, so MiG-15s were fitted with two 23mm cannon and a single 37mm cannon, which could literally blow apart a tank.