a drip pan apparatus for a “ m ” model black hawk ® helicopter and the like includes an expanded corner structure for accommodating an access port also positioned further outwardly in the corner than in prior drip pan apparatuses , facilitating filter viewing while retaining peripheral o - ring seal . an expanded corner of the airframe skirt is accommodated by the expanded corresponding corner of a frame , which also defines a small radius internal curve . the removable pan has a small radius curve cooperating with the small radius curve of the frame and is sealed thereto by the peripheral o - ring seal sealing the entire pan to the frame . physical access to the filter is enhanced .