Program objective is to develop a television system for identifying fuel tank leaks. This leak detection method uses a near infrared camera with illuminator to observe gas flow through any small breaches in the fuel tank wall. System performance is based on the physical principle that reflected scene irradiance is reduced in any area where an illuminator's spectral bandpass traverses a flowing gas with the corresponding absorptive bandpass. In subsequent discussion this leak identification system will be referred to as the Eclipse Detection System (EDS). Proof of concept will be accomplished by designing and testing a prototype EDS that detects the flow of selected unheated or cooled gas through fuel tank leaks. These prototype tests will show EDS's to be: (1) comparable in size and ease of operation to a conventional camcorder, (2) less expensive than proposed or currently available methods, (3) more user friendly, and (4) will provide improved imagery with leak areas shown as black spots and/or plumes on a TV monitor. Conversely, leak detection systems that rely on heated air or gas emissions require a more costly and complex setup to image and control the heated trace gases. Heated trace gases may be corrosive to some fuel tank surfaces.
