Abstract: An improved TCAS indicating system and method for displaying information from the MODE S TRANSPONDER or other subsystem, directly to the TCAS DISPLAY by coding the information and programming the TCAS COMPUTER and the MODE S TRANSPONDER to pass the coded information through to the TCAS DISPLAY.

Abstract: In an aircraft having an aircraft tracking system (ATS), the aircraft being a monitoring aircraft, the monitoring aircraft interrogates target aircraft in the vicinity of the monitoring aircraft in order to determine potentially dangerous situations. The target aircraft responds to the interrogations with parameter information which includes identification (ID). A method of interrogating the target aircraft comprises the steps of receiving unsolicited signals from the target aircraft in the vicinity of the monitoring aircraft. The received unsolicited signals are received by the monitoring aircraft at a first power level. Based on the first power level of the received unsolicited signals, the monitoring aircraft interrogates the target aircraft with a first interrogation signal.

Abstract: A radial keratotomy knife which includes an accurate linear position transducer for digitally displaying the extension of a surgical blade beyond a footplate on the knife. A system is also disclosed for zeroing the blade position relative to the footplate. The system includes a zeroing sleeve having a reflective membrane to reflect light to a detector. The knife is inserted into the sleeve so that the footplate is in contact with the membrane within the system contained within a console. When the blade is advanced to contact the reflective membrane from within the sleeve, the reflected light pattern is altered to establish accurately a zero position of the knife blade relative to the footplate. The knife is then withdrawn from the sleeve and the blade advanced by a micrometer so that the transducer produces a signal relative to the reference level indicating the extension of the blade.