Abstract: A passive Traffic Alert and Collision Avoidance System (TCAS) and method is based on receiving and processing Mode-S transponder messages without the TCAS computer having to interrogate the transponders of the respective aircraft flying in formation (i.e., a passive TCAS). A TCAS computer and Mode-S transponder are used to provide distributed intra-formation control among multiple cells of aircraft flying in formation or close-in. The Mode-S transponder provides ADS-B Global Positioning System (GPS) squitter data to the TCAS computer; the TCAS computer receives and processes the data without having to interrogate the transponders of the multiple cells of aircraft. The method and system allow a safe separation between 2 to 250 aircraft flying in formation at selectable ranges.

Abstract: A display presents to the viewer the outputs of a dual mode Traffic Collision Avoidance System (TCAS)/Intra-Formation Position Collision Avoidance System (IFPCAS). IFPCAS requires the cooperation of a least two formation follower aircraft in conjunction with the formation lead aircraft. The display indicates the relative velocity of the other formation follower aircraft, with respect to the formation lead aircraft, in addition to other types of information.

Abstract: An optical system having the features of a wide angle lens, a deep field lens and a close focusing lens is comprised of an objective lens, a field lens and a relay lens aligned on an optical axis in that sequence for the objective lens to form an intermediate image at or near the field lens and for the field lens and relay lens to transmit that same image to a smaller final image at the plane of the film of a film camera or charge coupled device of a video camera. The objective lens preferably has a fixed focal length and a wide open aperture for forming the intermediate image of a larger size than is otherwise normal for an objective lens of that focal length. Preferably, the relay lens has the iris and focusing mechanism whereby the objective lens and field lens are not required to be used for aperture control and focusing. The optical system provides an extended optical axis for accommodating lighting of a near object being photographed.