FIPS – form in place sealing – with Proseal

27 Jun 2005 FIPS – form in place sealing – with Proseal

Sounds eerily similiar to a widely used technique on many access panels installed on the nations combat aircraft. It is known as FIPS…….or……. form in place sealing. Typically, an access panel (or cover) is treated with some non-stick parting agent, the structure to which the panel is affixed is prepared and slathered with a healthy layer of proseal, the access panel/cover is temporarily screwed into place with a number of fiber “donuts” between the structure and the cover. The donuts were essential in providing a uniform thickness to the proseal gasket. The squeeze-out of wet waste proseal was immediately wiped away. After cure, the cover was removed, it and the structure were cleaned up, the donuts removed and the result was a gasket like layer of proseal that provides lasting air-tight moisture protection. In practice, the slightest void or uneven thickness in the proseal formed gasket was cause for the inspection department to reject your FIPS work and make you do it all over again. It was labor intensive work and I suspect Mooney chose not to get involved with the time and expense of FIPSing.

Rick Galati RV-6A “Darla”