AbstractUsing data obtainedin flight, three position determining algorithms for use by general aviation aircraft were evaluated representing increasing software requirements. These were a DME only, DME/air data and blended DME/air data. Although each step represented additional software with resultant increase in position accuracy, all could be performed on a programmable electronic desk calculator. Results from the computation of aircraft position using the three algorithms are presented. The algorithms employed can be extended to accept VOR, TACAN bearing, ADF, or other NAVAID Data. To obtain the flight data an experimental system was configured and flown on a general aviation aircraft. Principal hardware elements (all with low‐cost potential) were a programmable calculator, a single DME receiver (multiplexed for multiple DME use) and a low‐cost air speed sensor (shed‐vortex principle). The flight test demonstrated satisfactory performance of these principal ele