Over a span of about 23 years from 1967 to about 1990, records indicate around six General Dynamic F-111 Aardvark aircraft at the NASA Dryden Flight Research Center, Edwards, California. During this time span, four areas of significant flight testing stand out. The first tests occurred during the late 1960s when NASA worked on evaluating problems with the early F-111A (#63-9771 and #63-9777) for the Air Force and Navy. The early 1970s through the late 1980s brought the second and third phases of testing with an on-going effort to improve the F-111A (#63-9778). The second phase called transonic aircraft technology (TACT/F-111A) added an highly efficient supercritical wing and later the third phase applied advanced wing (Mission Adaptive Wing-MAW) flight control technologies and was called Advanced Fighter Technology Integration (AFTI/F-111A). The fourth effort, utilizing an F-111E (#67-0115), ran from 1973 to 1976, and used an engine with an electronic control system (fly-by-wire) in place of the traditional hydro-mechnical system. This program called the integrated propulsion control system (IPCS) helped validate the Digital Electronic Engine Control (DEEC) concept.

During the same period as F-111 TACT program, an F-111E Aardvark (#67-0115) was flown at the NASA Flight Research Center to investigate an electronic versus a conventional hydro-mechanical controlled engine. The program called integrated propulsion control system (IPCS) was a joint effort by NASA's Lewis Research Center and Flight Research Center, the Air Force's Flight Propulsion Laboratory and the Boeing, Honeywell and Pratt & Whitney companies. The left engine of the F-111E was selected for modification to an all electronic system. A Pratt & Whitney TF30-P-9 engine was modified and extensively laboratory, and ground-tested before installation into the F-111E. There were 14 IPCS flights made from 1975 through 1976. The flight demonstration program proved an engine could be controlled electronically, leading to a more efficient Digital Electronic Engine Control System flown in the F-15.