While the MiG-15 Fagot impressed Western observers during the Korean War, there were still considerable problems with its handling as it approached the speed of sound. It became so uncontrollable and near-sonic speeds, which it could reach in a dive, the speed brakes automatically deployed in order to prevent the pilot from exceeding speeds where he could control the aircraft. These problems were not limited only to the MiG-15 or to the Russians. The first swept-wing jet fighters all experienced similar problems as designers and engineers learned about near-sonic and supersonic speeds and how to make aircraft controllable at those Mach numbers. The U. S. F-86 Sabre, which fought the MiG-15 over Korea, had similar problems, and modifications were made to the wings and the tail surfaces to solve them.
In Russia, the MiG design bureau began making changes to the MiG-15 to solve these problems as well. They designated the new design SI, while the Soviet Air Force called it the I-330. Two prototypes, one converted from a MiG-15 airframe and designated SI-1, and the other converted from a MiG-15bis airframe and designated SI-2, were constructed. They had a completely redesigned wing, a longer fuselage, and a larger vertical tail when compared to the MiG-15. The SI-1 was used only as a static airframe and for wind tunnel testing, while the SI-2 began the flight test program. Strangely enough, the new design did not incorporate an all-flying tail but retained the conventional fixed horizontal stabilizer and moveable elevator combination instead. The benefit, indeed the necessity, of the all-flying tail for near-sonic and trans-sonic flight was already clearly recognized in the West. Later variants of the F-86 Sabre were fitted with this feature, and it would become standard on all subsequent American supersonic fighter aircraft.
Of the changes made, the new wing was the most obvious. It was thinner than the one used on the MiG-15, and it had rounded tips. The leading edge was not straight. The inboard part of the leading edge had a 49-degree sweep, while the outer section had a sweep of only 45.5 degrees. There were three fences on the upper surface of the wing rather than just two as found on the MiG-15. These fences prevented the airflow from sliding down the swept wing. The fuselage was lengthened slightly less than four feet, and a strake was added under the aft fuselage to improve lateral stability. Other design changes were made to the landing gear and elsewhere on the aircraft, but these were generally minor in nature. Many design features of the MiG-15 were retained, and many parts remained interchangeable between the designs. The armament of two NS-23 23-mm cannons and one NS-37 37-mm cannon remained unchanged and was fitted to the prototype.
Flight testing began on February 1, 1950, but after only a few weeks, the SI-2 was destroyed in a crash that also killed the test pilot. Two more prototypes soon replaced the lost aircraft, and the test program began again. During the testing, these aircraft demonstrated successful flight at Mach 1.03. In level flight, the prototypes were only about thirty miles-per-hour faster than the MiG-15bis, but the real advantage was the improved handling at high speeds. The test program concluded on June 20, 1951, and two months later, the aircraft was ordered into production as the MiG-17. NATO would later assign the reporting name, Fresco, to the new fighter.
In addition to the single 37-mm cannon and two 23-mm cannons, the MiG-17 had a single hard point under each wing for carrying external stores. When not fitted with external fuel tanks, bombs, rockets, or rocket pods could be carried on pylons installed on these hardpoints.
Although the MiG-17 production line began deliveries in August 1951, it wasn’t until June 1953 that the MiG-17 was put on public display, and Western observers initially thought it was a new variant of the MiG-15. To a large extent, it actually was, but the Soviet designation as a new aircraft was soon revealed. With the Fresco entering operational service in late 1951, it may seem that there was plenty of time for the new fighter to join the MiG-15 in Korea, but the Russians decided to keep it in their own fighter squadrons rather than evaluating it in combat alongside its predecessor. Meanwhile, some MiG-17s were modified and used as test aircraft for proposed variants and to evaluate new equipment.
One of the more interesting modifications was called Project SN. A solid nose with three 23-mm cannons was installed, and the cannons could be moved up or down in slots rather than being fixed. With this armament, the air inlet for the jet engine had to be replaced with two smaller inlets located in the wing roots.
Realizing the need for an all-weather interceptor, two developments of the MiG-17 were tested soon after the Fresco entered service. These were designated SP-2 and SP-7. The later was fitted with an Izumrud radar system mounted in the nose. The search radar was under a dome at the top of the intake lip, and the tracking radar was mounted inside a dome at the center of the divider in the intake. The aircraft was armed with three 23-mm cannons, because replacing the 37-mm cannon on the right side with a smaller and lighter 23-mm weapon helped compensate for the extra weight of adding the radar in the nose. The SP-7 went into limited production as the MiG-17P, and production aircraft were assigned to Soviet air defense squadrons of PVO Strany, the Russian equivalent of the U. S. Air Force’s Air Defense Command. NATO gave the MiG-17P the reporting name of Fresco B. Standard MiG-17s were then given the designation Fresco A.
By the early 1950s, the means of boosting the thrust of a jet engine with an afterburner had become known, and these devices began to appear on test aircraft and then on the production lines. The afterburner was very simple, consisting of an extended exhaust pipe into which jet fuel could be dumped to increase the volume and speed of the exhaust gases. But this increase in thrust was for temporary use only, because it came at the price of a considerably higher consumption rate of fuel.
The Russians modified the VK-1A engine by adding a short afterburner and redesignating the powerplant the VK-1F. The F stood for forsirovannyy, which is Russian for boosted. The maximum thrust was boosted from 5,950 pounds for the VK-1A to 7,451 for the VK-1F. The engine was installed in a SF prototype converted from a MiG-15bis airframe. With the new powerplant installed, the aft end of the afterburner nozzle extended beyond the tail section of the fuselage by several inches. Flight testing quickly demonstrated a marked increase in performance, particularly in time-to-climb numbers.
Other changes were made to the design, with the most noticeable being larger speed brakes on the aft fuselage which had much larger fairings covering their actuators. Small air intake slots were located near the top of the aft fuselage to improve cooling within the engine compartment, and the flare dispenser was moved from the right side of the fuselage to the right side of the vertical tail. Of special interest to the pilot, a new ejection seat was installed that was far more advanced and safer in operation than the one used in the MiG-15 and the MiG-17 Fresco A. The internal armament remained one 37-mm and two 23-mm cannons.
The new variant was placed in production as the MiG-17F, which NATO designated the Fresco C. It became the most numerous of all MiG-17 variants, with more than 8,000 being produced. The MiG-17F also had the distinction of being the first operational aircraft in the Soviet Air Force to be equipped with an afterburner. It would become one of the most widely exported combat aircraft of all time, and it proved to be very effective in combat, even when fighting against aircraft which, at least on paper, seemed to be vastly superior.
With the day fighter version of the aircraft now fitted with an afterburner, the next logical step was to develop all-weather interceptor versions that likewise had the benefit of the extra thrust of an afterburner. The performance figures of the MiG-17P Fresco B had suffered due to the extra weight of the radar system and its associated equipment. The addition of an afterburner would go a long way in solving this problem. Accordingly, the existing MiG-17P was modified to accept the new afterburning VK-1F engine.
The test aircraft was designated the SP-7F, and after testing, the new variant was placed into production as the MiG-17PF. NATO assigned the reporting name Fresco D to the new interceptor. Early production MiG-17PFs had the same RP-1 radar system used on the earlier MiG-17P Fresco B, but this was later upgraded to the RP-5. Armament was three NR-23 cannons with eighty rounds per gun. The substituting of a third 23-mm cannon for the 37-mm cannon used on the day fighters was again a way to compensate for the extra weight in the nose caused by the installation of the radar equipment. Nevertheless, the MiG-17PF had an empty weight of more than 550 pound heavier than the MiG-17F. It should also be noted that the installation of the radar necessitated moving the S-13 gun camera and its associated fairing to the right side of the intake lip instead of being near the top as it was on the day fighter variants.
The development of air-to-air missiles in the West did not go unnoticed by the Soviets, and they began working on their own designs. The first to reach operational status was the RS-2U, known as the AA-1 Alkali by NATO. This was a semi-active homing radar guided missile that rode the beam generated by the radar in the aircraft. This is the same principle used by the U. S. AIM-7 Sparrow missile. The first aircraft to be equipped to carry the RS-2U was the MiG-17PM. The three 23-mm cannons of the MiG-17PF were deleted, making this new version of the aircraft the first Soviet fighter to be armed solely with missiles. Two APU-4 launch rails were mounted under the inboard section of each wing, providing a total of four missiles for the aircraft. The RP-2U radar system was installed to search for targets, lock on, and then guide the missiles to their targets.
The MiG-17PM was assigned the reporting name, Fresco E, by NATO. It was not built in great numbers, leaving the MiG-17PF as the primary all-weather interceptor in PVO until it was replaced by radar-equipped MiG-19PMs and MiG-21C Fishbeds.
Not only was the MiG-17 widely exported by the Soviet Union, it was also built in two other countries as well. Communist China produced MiG-17Cs as the Shenyang J-5. Although the Russians never built a two-seat training version of the MiG-17, the Chinese did, calling it the JJ-5. It was essentially a J-5 with the two-seat cockpit arrangement of the MiG-15UTI Midget installed in place of the standard single cockpit. The JJ-5 also had a small radar installed in the upper lip of the engine air inlet. Like most MiG-15UTI trainers, it was armed with a single 23-mm cannon.
Poland produced a version of the MiG-17F as the Lim-5. They also built a limited number of Lim-5P reconnaissance variants. An attempt to develop a modified ground attack variant as the Lim-5M, and subsequently the Lim-6, met with little success, and few were produced. The Lim-6bis was an improvement over the Lim-6, but only seventy were built. The Lim-6R and Lim-6MR were photo-reconnaissance variants. When the Chinese and Polish production numbers are added to those of the Soviet Union, a total of more than 10,000 MiG-17s were produced.
Over many years of operational service, MiG-17s were flown by the air forces of Afghanistan, Albania, Algeria, Angola, Bangladesh, Bulgaria, Burkina Faso, Cambodia, Communist China, Republic of the Congo, Cuba, Czechoslovakia, East Germany, Egypt, Ethiopia, Guinea, Guinea-Bissau, Indonesia, Iraq, Hungary, Libya, Madagascar, Mali, Mongolia, Morocco, Mozambique, Nigeria, North Korea, North Vietnam, Pakistan, Poland, Romania, Somalia, Somaliland, Sri Lanka, Syria, Tanzania, Uganda, Yemen, and Zimbabwe.