Subsonic Long Range Strike: So Much for That

Vago Muradian, editor of Defense News, reports today that the US Air Force has awarded Lockheed Martin a classified contract to develop a hypersonic, unmanned spy plane that could evolve into a bomber.

How this plays with the USAF's announcement last month that it will seek to develop a subsonic, manned bomber for the long range strike mission by 2018 is unclear to us.

Read the full story here, or, if you prefer, here's an excerpt:

The Air Force has awarded Lockheed's Advanced Development Projects arm a top-secret contract to develop a stealthy 4,000-mph plane capable of flying to altitudes of about 100,000 feet, with transcontinental range. The plan is to debut the craft around 2020. The new jet -- being referred to by some as the SR-72 -- is likely to be unmanned and, while intended for reconnaissance, it could eventually trade its sensors for weapons.

Bill Sweetman, of Defense Technology International, follows-up with some useful insight on Aviation Week.com's Ares blog:

... Early last year I had a conversation with a senior Skunk in which he talked about the company's proposal for a new high-speed, high-altitude X-plane. The X-plane would be the size of a fighter and would be designed for a speed of Mach 6.5 -- 4300 mph -- at 100,000 feet. (The SR-71 Blackbird, retired in 1990, could manage up to Mach 3.3 in sprints at 85,000 feet). It would be powered by two jet engines -- bigger versions of the engine used on the Skunk Works' RATTLRS (Revolutionary Approach To Time-critical Long Range Strike) cruise missile -- integrated into ramjets. The speed -- less than DARPA'S Falcon Hypersonic Cruise Vehicle project or the USAF's X-51 scramjet demonstrator -- is important. At Mach 6.5, the vehicle can be powered by ramjets, rather than having to incorporate a scramjet (supersonic combustion ramjet) mode into the system. It would take off from a runway and land under power, not as a high-speed glider. It can burn near-standard hydrocarbon fuel, not hydrogen or a similarly exotic propellant. It could be made from conventional materials -- even composites -- with heat-resistant materials confined to the leading edges.