The success and safety of flight in actual instrument conditions is dependent upon the communicative competency of the individuals involved. The more obvious elements of communication involved include crew coordination and communication both verbal and nonverbal, aircraft and ground communication links, pilot interpretation of verbally and instrumentally derived information, and analysis of the nuances of accepted verbal phraseology. The pilot co-constitutes and maintains the "world" of instrument flight at various levels. This participation emerges as an expressive function as well as a cognitive task. An understanding of the fluidity of performance of certain pilots may be found by examining characteristic aspects that provide the qualitative background of the human experience of instrument flight. Expressive dimensions of communication are an integral part of pilot performance. The presence of the expressive region accounts for the difference noted between the "mechanical" pilots and those who have a "feel" for the aircraft. For the sake of flight safety, it becomes a responsibility to investigate and to attempt to understand how the instrument flight pilot incorporates the technology of flight and of instrumentation with every act of flight, with every thought, expectation, and remembrance. (HOD)