Following training, Maynard was sent the Station HYPO in Heeia, Hawaii where he served as a Japanese kanakona Morse code intercept operator. He was at Pearl Harbor on December 7, 1941 and probably witnessed the Japanese attack.
Prior to the Battle of Midway (4-7 June, 1942), Maynard was selected to join in a four-man direct support unit to deploy on the USS YORKTOWN (CV 5). The unit consisted of one Japanese Language Officer and three kanakona intercept operators. He was on the YOURKTOWN when the ship was hit by several Japanese torpedoes and bombs. As a result, the four member unit, along with one RIP-5 typewriter, and Admiral Fletcher’s flag staff transferred to the cruiser USS ASTORIA (CL/CA-34) via a whaleboat. The YORKTOWN eventually sank on June 7, 1942.