attack using the observation periscope

[Munchausen]

Yes, it works in the game.

In real life, observation scopes had a larger head, allowing for more light and a brighter image. The larger head caused a larger rooster tail (wake) in the water ... making it easier to detect. But bearings could still be taken from the observation scope and, even without a stadimeter, ranges could be estimated and plugged into the TDC.