The Development of an Optimized Unitary Warhead for the ERGM System

A unitary warhead concept for the EX 171 Extended Range Guided Munition (ERGM) gun-fired projectile is proposed that incorporates pre-formed fragments in combination with an integrated composite/metallic casing. The use of pre-formed fragments ensuresoptimal fragment output, while the composite/metallic casing provides the structural support required to survive gun launch. The casing is a combination of a thin inner metallic shell surrounded by pre-formed fragments that are contained within an outercomposite structure. In order to minimize weight, the composite structure will be designed to carry a majority of the structural load, with some structural load-bearing capacity also provided by the inner metallic shell. A composite casing will be designedto withstand the large accelerations and bending moments experienced during gun launch. Decoupling the fragments from the structural load-bearing capacity of the casing enables the incorporation of the most lethal fragments for the given target set. ThePhase I program will enable an assessment as to the practicality of using the proposed unitary warhead concept for the ERGM system, and for other munition systems currently fielded or in development. The systems could be other gun-fired projectiles andmissile systems for all of the DoD services. The primary beneficiary of the Phase II program research is the Department of Defense, especially those agencies utilizing weapon systems with fragmenting warheads. Potential commercial applications includeareas where high strength and high temperature composite structures are required. This could include composite over-wrapped pressure vessels (COPVs) for automotive natural-gas vehicle (NGV) tanks, composite risers for offshore oil drilling, integrallywound composite tubes/end fittings for the conversion industry, composite utility poles or lightweight sporting goods.