Sukhoi Su-9 (Fishpot)
The Sukhoi Su-9 Fishpot interceptor was typical of Soviet high-speed aircraft design for the Cold War period.
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During the Korean War (1950-1953), the age of the jet-powered fighter had arrived. Soviet MiG-15s regularly tangled with American F-86 Sabres in a "duel for the skies", solidifying the benefits of swept-back wings and jet propulsion. While the MiG-15 proved an excellent platform in its own right during the conflict (particularly when piloted by Soviet airmen), it was only inevitable that Soviet researchers and engineers continue development of more capable types. The Sukhoi concern, in operation since 1939, began work on a pair of missile-armed, supersonic interceptors with swept wings. After extensive aerodynamic testing of various design elements concerning supersonic flight, work began on a pair of aircraft that would eventually become the Sukhoi Su-7 ("Fitter") and the Sukhoi Su-9 ("Fishpot").
In 1959, the Soviets introduced the Sukhoi Su-7 fighter and the type went on to become the primary Soviet Air Force fighter in inventory while also doubling in a limited strike role. Its basic configuration involved use of a slim, tubular fuselage with swept-back wings and a single turbojet engine. It was produced from 1957 until 1972 to which some 1,847 were ultimately manufactured with operational use spanning both Soviet allies and satellite nations within the Soviet sphere of influence. In practice, the aircraft proved capable though it suffered from a limited weapons set and equally limited operational ranges. NATO codenamed the Su-7 the "Fitter".
Developed in parallel to the Su-7 was the Su-9 - the dedicated interceptor form. The development initially appeared in 1956 under the prototype designation of "T-405" and also incorporated a slim, tubular fuselage - though with delta-wing surfaces for the main appendages - and a single engine fitting. The program gradually evolved to enter serial production as the "Su-9" to which 1,100 to 1,150 examples were produced (sources vary). The type was first identified (along with the Su-7) by the West in the public Tushino Aviation Day presentation of June, 1956. The Su-9 was formally adopted for service in the Soviet Air Force in 1959 to which NATO authorities assigned the codename of "Fishpot". Unlike the Su-7, the Su-9 would serve exclusively with the Soviet Air Force, primarily as part of the Soviet Anti-Aircraft Defense umbrella.
Externally, the Su-9 exhibited a slim, well-contoured and relatively featureless fuselage from nose to tail. The single engine fitting was aspirated through a rounded intake opening at the nose, ductwork running under the cockpit floor. Within the intake was an adaptable "shock cone", then required of some supersonic flight airframes, and this installation also housed the included radar suite - the rather basic R1L series used to assist in the tracking and engagement of targets with missile weaponry. The cockpit was set some distance aft of the nose with the pilot residing under a two-piece canopy with heavy framing along the forward installation. Unlike the Su-7, which sported swept-back wings, the Su-9 was given a delta-wing configuration, these appearing as triangular shapes to each side of the fuselage. The delta-wing configuration was a proven commodity in supersonic aircraft design and allowed for more external hardpoints and internal fuel to be carried. Unlike the comparable American Convair F-102/F-106 delta-winged series of interceptors - which were true delta-winged aircraft - the Su-9 still retained a conventional empennage with a pair of horizontal tail planes and a single vertical tail fin - technically categorizing her as a "tailed delta-wing" aircraft. The undercarriage was of the traditional tricycle arrangement with two main landing gear legs under the wings and a nose landing hear under the cockpit floor. Seating was for one crew, intended to fly the aircraft, work the radar system and the onboard weaponry. Airbrake panels numbering four were located along the top and bottom sides of the fuselage. Power was supplied through the fitting of a single Lyulka AL-7 series turbojet engine of 19,840lbs thrust. Top speed was Mach 2.0 (1,325) at altitude with a service range equal to 700 miles and a service ceiling of 55,000 feet. Rate-of-climb was excellent at 27,000 feet per minute.
The power qualities of the Su-9 was quite good for, as an interceptor, the type was expected to reach operating altitudes within minutes, fly to the target area, engage and destroy enemy aerial targets - this most likely coming in the form of intruding American bombers (in the event of all-out war) or marauding high-altitude spy planes that consistently violated Soviet airspace.
As a radar-equipped interceptor, the Su-9 was an "all-missile" aircraft. She was typically fielded with a configuration of 4 x K-5 (AA-1 "Alkali") air-to-air missiles, two under each wing across a pair of hardpoints. Despite the advanced technology of radar and missiles at this point in history, the combination was not thoroughly accurate and the capabilities of the Su-9 would suffer the length of her career as a result. Two hardpoint positions under the fuselage (just aft of the cockpit) were plumbed for the carrying of fuel drop tanks for increased ranges. There was no internal cannon fitted into the design, limited her short-range combat prowess substantially.
As mentioned, the T-405 designation marked the Su-9 prototype. In production, the main definitive series mark became the basic "Su-9" designator. A modified version - the "Su-9U" - became a two-seat training conversion model which incorporated a second cockpit position with dual-controls for student and instructor seated in tandem. While retaining her combat capabilities (to certain extent), this variant lost some volume of internal fuel that severely restricted her operational ranges. Approximately 50 examples of this mark were produced and known under the codename of "Maiden" in NATO nomenclature. The "T-431" was a modified Su-9 developed to break the world altitude record - which it did in 1962 at 94,659 feet - bringing glory to Mother Russia for a time.
The Su-9 was further developed to become the Su-11 ("Fishpot-C") all-weather interceptor series. Externally similar to the Su-9, the Su-11 was of the same single-minded purpose though much upgraded from her basic Su-9 capabilities. Changes included a lengthened nose section, improved radar facilities and a more powerful Lyulka AL-7F-1 series turbojet engine with afterburner. Additionally, missile armament was upgraded though the mount still lacked use of an internal cannon for close-in work. Roughly 108 of this version were produced and, again, used solely by the Soviet Air Force. The Su-11 was introduced in 1964.
The Su-9 series managed only a short operational lifespan with the Soviet Air Defense Forces for technological advancements quickly sheltered the type from frontline service. The type was never exported (not even to Warsaw Pact allies) so her global reach was virtually non-existent - she was instead held at home to patrol and protect the vast Soviet airspace. While incorporating more fuel into her delta-wings than the parallel Su-7 design, the Su-9 still suffered from limited operational ranges considering the airspace she was charged with defending - such were the limitations of the early generation, fuel-thirsty turbojet engines. Pilots, however, lauded her flight characteristics though the mount was known to "weed out" pretenders from contenders so some experience in her nuances was required for ultimate success. The lack of internal cannon severely limited her tactical capabilities.
The Soviet Union discontinued use of the Su-9 in or around 1980 thanks to the arrival of more capable interceptors. Ultimately, all interceptor types were done in by improved surface-to-air missile capabilities and "air superiority" fighters beginning to take center stage. Out-of-service Su-9s were either scrapped, cannibalized or developed into aerial target drones for training - the latter becoming the death call for many-an-aircraft of the jet age.
A single, unarmed Su-9 attempted to ram the CIA's Lockheed U-2 spy plane of Francis Gary Powers in May of 1960. While the direct attempt was unsuccessful, the U-2 was eventually downed by Soviet ground-to-air missiles spawning the embarrassing and tension-filled "1960 U2 Incident". This incident did mark the first use of the Su-9 as an "interceptor" in a way.
NOTE: The Su-9 of 1959 shares the designation of the "Su-9" of 1946, both developed by the Sukhoi concern. The development of 1946, however, was a copy of the German wartime Messerschmitt Me 262 "Schwalbe" ("Swallow") twin-engined, single-seat jet fighter which made a limited appearance in World War 2 with some 1,430 produced. As such, the two designations should not be confused when possible.