Engineering model for the first of a series of LOw Frequency Trans-Ionospheric (LOFTI) radio satellites. LOFTI satellites were one of the very early orbiting spacecraft intended to study the propagation of radio waves through and by the ionosphere. The experiment was also designed to determine whether low frequency radio signals penetrated water reliably enough to be used for communications with submerged submarines. The first in the series, LOFTI-1 was launched on a Thor-Able rocket in 1961; the scheduled separation from the Transit-3B satellite to which it was attached failed. Much valuable data on VLF and VHF transionospheric transmission was obtained in spite of the satellite's resulting shortened time in orbit. This artifact was transferred to NASM from the U. S. Naval Research Laboratory in 1975.
Transferred from the Naval Research Laboratory