Prewar planners repeatedly assumed that their mobilization calendars would leave enough time to replace aging equipment before combat. The Navy recognized the TBD's growing obsolescence, yet only began the earliest Avenger work around 1940 and moved through development slowly. Meanwhile the TBD inventory shrank as whole units shifted to training and individual aircraft became target tugs. Britain planned Flower-class corvettes and Hunt-class escort destroyers around an expected 1942 war, only for fighting to begin before those escort programs could mature on schedule. Japanese planners came closest to predicting when their war would start, yet their procurement program still did not make the resulting force viable on that timetable. The Avenger entered service only in 1942, leaving the old torpedo bomber to face a war that arrived before the planned transition was ready.
Chapter · 36:57-40:30
The Avenger replacement effort started too late
The Navy knew the TBD was becoming outclassed but moved slowly enough that its successor did not enter service until 1942.