Russia's Defense Ministry has signed a 30 billion ruble ($630 million) contract with a major state-owned aircraft manufacturer to modernize over 50 of its high-speed MiG-31 interceptor jets, the RIA Novosti news agency reported.
The move comes amid a 20 trillion ruble ($500 billion) ongoing state rearmament program and rising tensions over Ukraine that have seen Russian jets repeatedly test the boundaries of NATO airspace in recent months.
"The armed forces will receive over 50 modernized MiG-31s by the end of 2018," RIA quoted Deputy Defense Minister Yury Borisov as saying Thursday. The modernization will be carried out by Russia's largest aircraft manufacturer, United Aircraft Corporation.
The MiG-31 is a classic Soviet aircraft. Designed in the 1970s as a follow on to the MiG-25 supersonic interceptor jet, the plane is a supersonic bomber killer.
Around 120 of the fighters remain in service today, RIA reported.
The aircraft can fly to altitudes of 20,000 meters and reach a maximum speed of Mach 2.83 (3,000 kilometers an hour), making it an ideal defensive fighter. If Russia were to detect foreign reconnaissance or bomber planes entering its airspace, the MiG-31 could quickly chase down and destroy them before their targets are reached.
Modernized MiG-31s are outfitted with new avionics and fire control systems, and can simultaneously fire on six targets within a 280-kilometer radius.
The U.S. and most other Western air forces phased out dedicated bomber interceptors by the time the MiG-31 entered service in 1975, as the focus of Soviet nuclear strategy focused on ballistic missiles. However, the Soviets saw continued need to operate fighters capable of dealing with the comparatively massive U.S. strategic bomber fleet in the event of nuclear conflict.
Russia has already modernized around 20 MiG-31s, according to media reports. A separate contract to modernize 60 of the aircraft by 2020 was signed with United Aircraft Corporation in 2011, RIA reported.