A chemical cleaner used to loosen dirt, grease, oxides, and carbon deposits from the surface of an aircraft. Solvents are mixed with water and a petroleum product, such as naphtha. An emulsifying agent is used to form an emulsion with these products that do not normally mix.

The cleaner is sprayed on the dirty surface and allowed to remain long enough to penetrate the surface contamination and reach the metal. Then it is washed off with hot water or steam.