Experimental fighter F-107A "Ultra Saber" (USA)

2024 Author: Matthew Elmers | [email protected]. Last modified: 2023-12-16 21:49

At different times, in different countries, a large number of aircraft for various purposes were produced. Among them were created admirable and regrettable that these winged machines did not leave a significant mark in the history of aviation. In most cases, they remain in the models, sometimes they "live" up to flight tests and, in rare cases, get into the museum as exhibits. These examples include the F-107A "Ultra Saber" fighter-bomber developed by North American Aviation. North American's credibility in the first half of the 1950s in the development of fighter aircraft seemed to be unshakable. The company took off to the top of the American aviation industry during the Second World War after the creation of a successful front-line bomber B-25 Mitchell and one of the best fighters of that time - the P-51 Mustang. The accumulated experience, powerful production and personnel potential, as well as the opportunity to investigate captured German developments in the field of aviation enabled the North American in the second half of the 1940s to successfully enter the jet era with the F-86 Saber fighter.

F-86 Saber

Since its debut in Korea, the Saber has established a reputation as the "king of fighters". Republic F-84 Thunderjet, Lockheecl F-80 Shooting Stare, aircraft of the closest competitors, "squeezed" into the category of fighter-bombers. Also, by order of the fleet, serial production of the deck variant of the "Saber" - the FJ1 Fury fighter was carried out. In addition to the United States, Sabers were built in Australia, Canada, Italy and Japan, and their total number reached almost 8 thousand. They were used for a long time in the air forces of 30 countries. North American in 1949, building on its success, began designing its first supersonic fighter, the Saber-45, or Model NAA 180. On this aircraft, it was planned to install a wing with a sweep of 45 degrees. However, at this time, the Pentagon gave priority in funding to strategic bombers - carriers of nuclear weapons. In this regard, the development of fighter programs has slowed down significantly. Only at the end of 1951, on the basis of the "Saber-45" was completed the development of the project of a new fighter F-100, intended to gain air superiority. In January of the following year, we signed a contract for its construction. The excellent reputation of the F-86 was the impetus for the fact that the campaign decided to undertake a successful marketing move - the new car was named "Super Saber". The prototype YF-100A took off on May 5, 1953. Already in the first sorties in level flight, it exceeded the speed of sound.

The first production F-100A was built on October 29th. Thus, the North American aircraft became the world's first serial supersonic fighter. Soon, Lt. Col. Frank Everst from the Air Force Test Center reached 1216 km / h at the ground on this plane. On September 27, 1954, after a number of modifications, the F-100A was officially adopted. But, despite the Cold War, the customer's interest in the "clean" fighter dropped significantly. Even the US defense budget could not pull the development of several diverse programs. The era of multipurpose aircraft took its beginning. Tactical Air Command (TAC, Tactical Air Comnnand) in December 1953 recommended the company to manufacture a new version of the "Super Saber", which could perform the tasks of not only an interceptor, but also a fighter-bomber. This proposal was embodied in the modification of the F-100C. This aircraft had a reinforced wing with fuel tanks and six underwing weapon attachment points. The F-100C could carry 2,270 kilograms of bombs and missiles, including tactical Mk.7 nuclear bombs. The aircraft could be fitted with a “hose-cone” air refueling system. On August 20, 1955, the F-100C set a world speed record of 1323 km / h.

Almost all of the first supersonic aircraft entered service through a series of serious flight accidents. Super Saber was no exception. On October 12, 1954, George Welch, Chief Pilot of the North American Company, was killed. During the exit from the dive with a large overload, the aircraft began to swing longitudinally and transversely. As a result, the plane collapsed in the air. To prevent the occurrence of this problem in the future, the pitch and roll control system was changed. Moreover, most of the innovations were introduced directly on the assembly line, and the finished fighters were returned for revision. Despite this, the "Super Saber" went down in the history of the US Air Force as an aircraft with a high accident rate. One of the factors that contributed to this was the high landing speed, which reached 330 kilometers per hour. This is due to the fact that the aircraft did not have flaps or landing flaps, for which there was simply no room on the wing, since, due to the danger of reversing the ailerons, they had to be moved to the fuselage.

F-100D

The most advanced and massive (1274 copies produced) modification of the "Super Saber" was the F-100D fighter-bomber, which was created in 1956. The car received an autopilot and improved electronic equipment, as well as a bomb load increased to 3190 kg. To improve track stability, the vertical tail area was increased by 27 percent. The wing has been significantly modified. Its span was increased to 11, 81 m (11, 16 m), and a root inflow was performed along the trailing edge, which made it possible to install flaps. In total, 2294 fighters of various options were built by October 1958. These machines were used until the early 1980s. Even before the creation of the F-100A, it was clear that the race for speed was far from over. In the Soviet Union, the MiG-19 fighter was developed, and the development of projects for supersonic bombers began. What was needed was an airplane capable of flying at twice the speed of sound. Naturally, North American tried to make the most of those. groundwork for the F-100.

In early 1953, the company received preliminary requirements from the US Air Force for an improved Super Saber. On the basis of the F-100 in March 1953, two variants of the project were prepared: the F-100BI fighter-interceptor or "model NAA 211" (letter "I" - "Interceptor") and the F-100B fighter-bomber or "model NAA 212" … In light of the "current preferences" of the Tactical Air Command, it was decided to concentrate on the second option. On the fighter-bomber, designed at a speed of about 1.8 M, it was planned to install the P&W J57 engine, as on the Super Saber, but with a modified nozzle design. The design of the nose of the fuselage was to be similar to the F-86D fighter-interceptor. But there was a problem with the organization of the supersonic air intake. In this regard, in June 1953, the project was again radically altered. The F-100B received a new dorsal air intake with sharp edges and an automatically adjustable central wedge, the so-called VAID (variable-area inlet duct) or variable area inlet. The upper location of the engine air duct and air intake made it possible to raise the wing and organize a zone under the fuselage for the semi-submerged placement of special ammunition (tactical nuclear bomb B-28 or TX-28) or an additional fuel tank with a capacity of 250 gallons (946 liters).

The nose part, made in the form of a flattened cone, and the canopy with a large glazing area provided excellent downward and forward visibility, which is very important for an attack aircraft. The lantern cover was folded up, and this did not allow starting the engine until it was closed. The aircraft was equipped with a modified wing from the F-100C, but it had a rear inflow and flaps. Roll control was carried out using spoilers on the lower and upper wing surfaces. The main landing gear was moved to the fuselage. The landing gear was retracted against the flight. The most interesting innovations applied on the F-100B were the all-turning (3 degrees to both sides) vertical tail of an increased area, which improved the directional stability of the aircraft. An integrated weapon control system HMA-12 was installed on the aircraft, the mass of the bomb load was increased to 4535 kg.

In October 1953, a full-size model of the fighter was built, which looked very futuristic by the standards of that time. Around the same time, the decision was made to use the latest P&W YJ75-P-11 turbojet engine. According to calculations, this made it possible to increase the speed to 2M. On June 11, 1954, a contract was signed between the developer and the Air Force for the construction of 33 F-100B fighter-bombers. The first three of them were intended for flight tests. North American was so confident of victory that on July 8 the aircraft was given a new designation F-107A (the designation was missing the first letter "Y" indicating the pre-production aircraft). The developer, promoting his project, made an attempt to offer the fleet aviation under the name "Super Fury" deck version, but this did not give results.

The official design of the F-107A was launched on May 1, 1955. Test pilot Bob Baker on September 10, 1956, lifted the F-107A into the air from the runway of Edward Air Force Base. During this dive flight, it was possible to reach a speed of 1.03M, but then the engine regulator pump failed. The pilot had to make an emergency landing. The increased landing speed (more than 360 km / h), caused by the failure of the flaps and the failure of the hydraulic system, as well as inoperative wheel brakes caused the mileage to be 6,700 meters. The plane drove onto an unpaved safety lane, where it damaged the front landing gear. The plane was quickly restored, and already on October 1, it developed a speed of 2M. In total, 30 flights were performed at the first stage of testing. In the second stage of testing (03.12.1956 - 15.02.1957), the second prototype was also involved, on which 32 flights were made. After that, the plane was used to practice the use of weapons. The pilots said that in comparison with the F-100, piloting the F-107A was more enjoyable. For the third stage of testing, the third and last F-107A was built. The operation of the air intake was tested on it in various flight modes. At the same time, on the first prototype, several climb tests were carried out, during which, during the climb, the aircraft exceeded the speed of sound.

North American was not the only developer fighting to win. "Republic", which had vast experience in creating fighters, in 1952 came out with an initiative proposal and entered into a contract with the tactical aviation command for the design and creation of 199 machines (later their number was reduced to 37 copies), created to replace the F-84F fighter-bombers Thunderstreak. The new aircraft was intended to deliver tactical nuclear weapons and conventional aerial bombs at supersonic speed in various weather conditions. The full-size mock-up of the fighter, named YF-105 and proper name Thunderchief, was built in October 1953. The final task was formulated in December 1953. At the same time, a contract was signed for the supply of 15 pre-production aircraft. It was planned to build 2 copies of the YF-105A intended for preliminary flight tests, 3 prototypes of the RF-105B reconnaissance aircraft (renamed JF-105B), 10 in the F-105B version intended for military tests. Since the required P&W J75 engine was not yet ready, the YF-105A was built with the "old" P&W J57. It was planned to install a new power plant from the third prototype.

On October 22, 1955, the first flight of the YF-105A took place - thus, it was ahead of the competitor by almost a year. Naturally, it was outperformed by the F-107A in almost all respects, except for the presence of an internal bomb bay, as well as the newest M-61 Vulcan super-fast cannon, which made it possible to get by with one gun, not four. The F-105B was more or less equal to the competitor, but the F-105D, which appeared two years after the end of the competition (in 1959), was a truly full-fledged tactical strike aircraft. In the summer of 1957, the leadership of the Air Force issued a final verdict. The YF-105 "Thunderchief" was victorious. 923 copies were produced. Most likely, the Pentagon made a political choice. At the time, Republic had no other software in development, and North American was fully loaded. At the same time, the first studies of the XB-70 supersonic strategic bomber, the A-5 Vigilante supersonic carrier-based nuclear weapons carrier, and a number of other programs began. Thus, the military wanted to keep the "Republic", and the F-105 became a "lifeline" for it.

YF-105A

Probably, the Americans were right. During the war in Indochina, the F-105 demonstrated very high survivability and earned the love of the crews. And although the operational and combat losses of "Thunderchiefs" amounted to 397 vehicles (almost 45 percent of the number produced), they completed 75 percent of all bombing missions. But the F-107A in the history of "North American" was the last fighter. After the lost tender, the construction of the remaining aircraft was canceled. The prototype F-107A was tested for some time on the use of weapons, including special ammunition, the discharge of which was worked out at speeds up to 2M. The two remaining copies were transferred to NACA, where they were used to develop a supersonic air intake and an all-turning keel. On September 1, 1959, one of the aircraft crashed on takeoff and did not fly again. It was used to train firefighters. The remaining cars were later transferred to museums, where they are still kept.