POWER: 2 x Lyulka AL-7F turbojet engines developing 19,840 lb thrust with afterburner (14,330 lb dry).
The Lavochkin concern of the Soviet Union became perhaps best known for its contribution of fighters during World War 2 (1939-1945). In the post-war years, the company attempted to keep pace with others worldwide in pursuit of viable jet-powered designs. This development stood alongside the growth in missile technology which was seen by many as the long term replacement for onboard cannon. The line of Lavochkin aircraft came to an end with several developmental types with the last official entry becoming the Lavochkin La-250 interceptor.
Prior to the widespread acceptance of submarine-launched ballistic nuclear missiles the primary threat for both sides of the Cold War was the long-range, high-flying heavy bomber which, in some cases, could out-fly ground-based defenses and fast-responding interceptors. For the Soviets, whose empire spanned a great many kilometers from east-to-west and north-to-south, the threat was primarily strategic bombers emerging from the United States. As such, a 1954 Soviet requirement officially called for a long-range, high-altitude missile-armed interceptor (the "Interceptor 250") to counter the threat at hand. From this was formed the La-250 design which was to be paired with the "Vozdukh-1" ground control radar guidance system (the "Uragan", or "Hurricane", with 18.5 mile acquisition range) and an onboard missile fire control system manning the proposed liquid-fueled K-15 air-to-air missile (the model "275"). Two of these missiles would be carried by the aircraft.
At its core, the aircraft showcased smooth, well-contoured lines with all wings being swept for maximum aerodynamic efficiency. The nose cone section was intended for the powerful radar fit. The twin K-15 beam-riding air-to-air missiles were carried along the fuselage in semi-recessed positions. The mid-mounted wing mainplanes were swept-back elements and propulsion was through 2 x Klimov VK-9 turbojets. Each engine was aspirated by a semi-circle intake seated to either side of the cockpit walls. A sole vertical tail fin was featured on the empennage and a tricycle undercarriage would support the aircraft when on the ground. Seating in the cockpit was for one. One of the key engineering features of the aircraft was its complete power-assisted control surface scheme with built-in backup (non manual form).
As it stood, the interceptor was to be operationally fielded as a single-seat form but, for testing purposes, prototypes were completed with a second cockpit to help collect data and other pertinent information during design and trials. The La-250 was available in prototype form for 1956 to which a first flight was conducted on July 16th. Issues with the engines forced a switch to the lower-rated Lyulka AL-7F series (14,330 pounds thrust) and the temperamental K-15U series radar fit gave way to the K-15M model. This, in turn, forced a change to the lighter weight "275A" missile form.
After a rewrite of the design, the La-250A emerged and this model featured a delta-wing planform, doing away with the original's swept-wing appendages. The missiles were also relocated from their semi-recessed fuselage positions to underwing hardpoints. The second prototype emerged in June of 1956 but was lost in a landing accident on November 28th, 1957. The third prototype was also crippled by a landing accident, this occurring on September 8th, 1958. A fourth and fifth prototype followed.
These five aircraft were all that was realized in the La-250 program for continuous delays from accidents and unreliable equipment helped to ensure that the investment was abandoned by the Soviets (the missile program itself was abandoned in 1959). As designed, the aircraft held a maximum speed of 1,243 miles per hour, about Mach 1.88, a range out to 1,240 miles and a service ceiling up to 55,750 feet which would have given it strong performance against enemy bombers of the period.
During its development program, the La-250 garnered the nickname of "Anaconda" for its unique, slim shape.