The machinery in the CANNON class Destroyer Escorts was very similar to the machinery that powered diesel electric submarines (see the Bowfin site) of the same period. Diesel engines drove DC generators that powered electric motors coupled directly to the propeller screws. Speed was controlled by a rheostat that varied the amount of current going to the motors. The first class, EVARTS, used these GM V-12 Diesels in Tandem and are referenced as General Motors Tandem Diesel or GMT. In the CANNON class the engines drove seperate generators and was called Diesel Electric Turbine or DET. The EDSALL class used the Fairbanks-Morse Diesel Engine with final drive through a reduction gear and was coded FMR. Other classes, such as the BUCKLEY and RUDDEROW classes, used steam driven turbines to generate electricity for the drive motors and were referred to as TE and TEV. The BUTLER class used a Westinghouse geared steam turbine and were WGTs. The DETs had a longer range but were slower, and while the steam versions were faster they had shorter ranges. Consequently, the steam versions (TE, TEV and WGT) were typically with fleet operations in the Pacific while the GMTs, DETs and FMRs were used for Atlantic convoys.

Some information taken from Submarine Main Propulsion Systems, NAVPERS 16161, June 1946, as presented on the Bowfin site. Thanks also to MoMM2c George D. McCarthy of the USS Hilbert DE 742 who has provided extensive engine details.