USS Wolverine and USS Sable train carrier pilots

Wolverine and Sable had no armor, hangar, elevator, or combat armament; their purpose was repeated takeoff and landing practice on the Great Lakes. Conversion was economical because suitable civilian hulls were available, broad, and stable, with paddle boxes acting rather like outriggers in choppy water. Pilots could land, refuel when necessary, take off, and repeat the cycle until carrier operations became familiar. Britain used whichever escort carrier could be spared from convoy work for similar practice off its own coast because it lacked an equivalent protected lake. Both methods belonged to a larger Allied system that rotated experienced pilots into training roles, while Japan kept veteran aviators in combat until attrition hollowed out its training base.