[4] As western Atlantic coastal convoys brought an end to the second happy time, Admiral Karl Dönitz, the Befehlshaber der U-Boote (commander in chief of U-Boats), shifted focus to the mid-Atlantic to avoid aircraft patrols.

[6] U-135 discovered and reported the convoy on 22 August while patrolling a formerly assigned station after having missed the signal to change position.

As Viscount was dropping depth charges, U-176 and U-438 entered the front of the convoy to torpedo Trolla and Empire Breeze.

The calm sea conditions were favourable for the Type 271 centimeter-wavelength RADAR with which all the escorts were equipped, and prompt counter-attacks prevented the U-boats from reaching torpedo launch positions.

[1] U-705 suffered several casualties when hit by gunfire from the convoy escorts; and was sunk in the Bay of Biscay by Armstrong Whitworth Whitleys of No.

[7] The ships in the convoy dispersed off Cape Cod on 3 September to proceed independently to North American ports.