Some types of navaids, such as Non-directional beacons and Distance Measuring Equipment, do not operate on these frequencies; in the case of NDBs the Low frequency and Medium frequency bands are used between 190–415 kHz and 510–535 kHz.
Also on board were former war correspondent John F. Chester and US Civil Aeronautics Administration officials George T. Williams and John D. Rice, both engaged in the development of airport radar systems and navigational aids.