Torpedo Options

[Sailor Steve]

The part about it taking an hour came from a source posted here back when I was homeless, and unable to save the link. The original poster also provided photographs, but I don't have those either. Perhaps you'll be happier with this source, which says it couldn't be done at all.

Since it was not yet possible to switch the pistols between the AZ and MZ settings, to overcome this problem the TI recommended that against such targets of less than 3,000 tons only torpedoes with the AZ type pistol be used.

In any case, the order had little to no impact, at least at first. At the time U-boats carried torpedoes equipped with either the MZ or AZ pistol. The option that would later allow the commander to interchange these settings while on patrol had not yet come into being, so whatever setting the pistol was set to when delivered to the boat was what it was stuck with for the duration of the patrol.

http://eaglescholar.georgiasouthern.edu:8080/jspui/bitstream/10518/3627/1/Wright_David_H_201005_MA.pdf

Pages 47-48.