On August 1, 1942, a J4F-1 flown by US Coast Guard Patrol Squadron 212 based out of Houma, Louisiana, and flown by Chief Aviation Pilot Henry White, spotted and attacked a German U-boat off the coast of Louisiana.

White reported the submarine sunk, and he was subsequently credited with sinking U-166 and awarded the Distinguished Flying Cross.

[3] The sinking of a German U-boat by the Civil Air Patrol (CAP) was claimed by one of their larger aircraft on 11 July 1942.

The Grumman G-44 Widgeon, armed with two depth charges and crewed by Captain Johnny Haggins and Major Wynant Farr, was scrambled when another CAP patrol radioed that they had encountered an enemy submarine, but were returning to base due to low fuel.

After scanning the area, Farr spotted the U-boat cruising beneath the surface of the waves.

Debris appeared on the ocean's surface, confirming the U-boat's demise and the CAP's first kill.

The conversion features replacing the engines with 270 hp (200 kW) Avco Lycoming GO-480-B1D flat-six piston engines, and various other modifications, including modern avionics, three-bladed propellers, larger windows, improved soundproofing, emergency exits, and increased maximum takeoff weight.