A VFDR (Variable Flow Ducted Rocket produced by Aerojet Rocketdyne) is a Ramjet using fuel which is the effluent of a solid propellant gas generator. The fuel flow is metered by a hot gas valve prior to injection in the Ramjet Combustor.
The "Coyote" Supersonic Sea Skimming Target (SSST) is the only Ramjet Propulsion System in the U.S. currently operational and in production. Particularly, the SSST uses the VFDR Propulsion System.
The next generation SSST VFDR systems use an advanced VFDR fuel. Both the current State-of-the-Art and Next-Generational Fuel models feature 7-inch dual inlets and can achieve Mach 3.25 at 30,000 feet.
- Feb. 28, 2011 - Aerojet Receives San Fernando Valley Engineers Council Award for U.S. Navy Coyote Program
- Aug. 13, 2010 - Aerojet's Ramjet Propulsion Engine Successfully Meets Coyote High Diver Mission Requirements on U.S. Navy's Initial Flight Test
- July 6, 2006 - Aerojet Awarded Contract for Supersonic Ramjet Engine Production
- Feb. 25, 2005 - Aerojet’s Supersonic Engine Successful in Critical Flight Test