The main goal of this project is to develop a superior corrosion preventive compound (CPC) which can be applied by fogging into an airframe for long term protection to minimize environmental effects on aging aircraft. As aircraft age, corrosion often occurs in internal structures which are not easily inspected or treated, especially in harsh environments where humidity, salt and heat conspire to reduce metal parts to piles of oxide. Fogging CPC’s into internal spaces of airframes has been shown to be effective in combating metal degradation; however, the CPC must be reapplied several times annually, using time-consuming procedures. In the first phase of this project, several commercial CPC products were evaluated for corrosion protection. The best and worst CPC’s were analyzed qualitatively to identify both useful components, and those that should be avoided for an optimized in-house formulation development effort. Products were found to contain basically three types of components-solvents, oils, and additives. Solvents were typically high flash mineral spirits. Oils were either paraffinic or naphthenic petroleum oils. Additives consisted of steel corrosion inhibitors (such as petroleum sulfonates, carboxylic acids, and oxidized petroleum fractions), copper corrosion inhibitors (such as triazoles) and anti-oxidants (such as alkylated aromatic amines). Software was used to optimize the blend between solvent, oil, and additives to achieve acceptable water-displacement, liquid penetration, corrosion protection of steel and aluminum, foggability, and low flammability. Several formulations were developed and tested in accordance with MIL-C-81309. The selected formulation has exceeded the specification requirements. The new CPC formulation has shown superior corrosion resistance in the salt spray test on aluminum and steel panels (ASTM B117) compared to commercial products conforming to MIL-C-81309 Type II. A test plan has been developed to perform an in-service evaluation on the candidate formulation.