a helicopter drip pan apparatus for covering and sealing a structural opening in a helicopter . the drip pan apparatus includes a frame member adapted to mount to the structural opening of the helicopter . the frame member has an inwardly - facing peripheral surface extending around the frame member . the frame member and thus the surface have at least one linear portion . a drip pan is selectively affixed to the frame member . the drip pan includes an outwardly - facing peripheral groove which extends around the outside edge of the drip pan . like the surface of the frame member , the groove has at least one linear portion . the perimeter of the drip pan conforms to the surface of the frame member . a seal member is disposed in the groove of the drip pan to sealingly engaging the surface of the frame member against fluid leakage therethrough .