Aerojet announced today that its Supersonic Sea-Skimming Target (SSST) ramjet propulsion system successfully completed the first flight test of the Coyote High Diver variant supersonic target mission. Orbital Sciences Corporation (Orbital) developed the target vehicle and uses Aerojet's solid-fueled Variable Flow Ducted Rocket (VFDR) propulsion engine. Orbital upgraded the original SSST configuration with guidance software modifications that enable the vehicle to operate at altitudes up to 50,000 feet. During the naval test at San Nicolas Island, Calif., the Coyote High Diver vehicle was rail-launched from the ground and boosted by a solid rocket motor to ramjet-takeover speed. Under ramjet-power, the system ascended subsequently to an altitude of 35,000 feet and reached a cruise speed of approximately Mach 3.3. At the end of its 110 nautical-mile-long flight, the vehicle executed a planned 40-degree unpowered dive to its objective point near the ocean’s surface. This flight mission was crucial in validating the vehicle's suitability for future high-altitude naval threat simulations and anti-missile response system tests. "It is of key logistical significance that the Aerojet-provided VFDR engine is 100 percent the same configuration for both the low-altitude SSST and the high-altitude Hi Diver flight missions," said Eric Coble, Aerojet’s VFDR program manager. Aerojet’s Executive Director of Force Projection & Protection, Dick Johnson, added: "We have invested significantly in this ramjet propulsion technology over the last several decades and today, Aerojet is the world’s first (and still only) manufacturer of production solid-fueled VFDR propulsion vehicles. The Coyote High Diver vehicle provides great flexibility to the Navy for capable variant targets without the additional development, production costs and schedule usually associated with vehicles providing significant new capabilities." Aerojet is a world-recognized aerospace and defense leader principally serving the missile and space propulsion, defense and armaments markets. The VFDR was originally developed by Atlantic Research Corporation (ARC) under an Air Force Research Laboratory (AFRL) contract. ARC Propulsion conducted a flightweight ground test of the VFDR engine in 1997, completing more than 20 years of design and development work by the Air Force Research Laboratory's Propulsion Directorate. The successful flightweight ground test demonstrated the technology was ready for flight testing. ARC sold its propulsion unit to Aerojet in 2003. The VFDR is a type of solid fuel ramjet. A rocket motor initially accelerates the missile to ramjet speed. The rocket motor casing then serves as the combustion chamber for the ramjet. The ramjet sustainer engine consists of an end-burning solid fuel motor which ejects a fuel-rich gas into the combustion chamber. This fuel-rich gas then mixes with ram-compressed air to provide the ramjet propulsion. A valve controls the the flow of the fuel rich effluent from the end-burning solid fuel motor into the ramjet combustion chamber. -- Aug. 13, 2010 In other news...