Unlike later packs which had specific code names this formation was left without an official designation.
The last boat, U-40, which was delayed in departing, was ordered to take the southabout route through the Channel; this was more dangerous, but was deemed practicable.
In the event U–40 became trapped by the Allies' Channel defences, the Dover Barrage; on 13 October she struck a mine and was destroyed.
The German signals intelligence branch, B-Dienst, which had penetrated British naval codes, was able to give notice of a convoy (KJF 3) from the Caribbean and BdU instructed the pack to intercept.
[2] The experience was also soured by the continuing torpedo problems that the U-boat Arm suffered during the first years of the conflict.