[Von Due]

It appears that adding 4 seconds to the runtime for a straight run will give a good approximation for runtime for a 90 degree turn set at the same distance.

The torpedo travels about 100 meters in 4 seconds on fast speed (avg. speed appr. 44.5 kts). The added distance comes from the turn so the arc of the turn must be about 100 meters. Since the arc length for a 90 degree turn

a = 1/2 pi*radius,

this corresponds to a turn radius of about 63.66 meters which is about 2/3 of the historical accurate turn radius of 95 meters.

The torpedo will travel parallell to line of sight to the 270/90 bearings at a distance of roughly 136 meters. It's not exact but should be accurate enough for medium to large size targets.

More importantly, the runtime and distance between torpedo track and the 270*/90* bearings are the same for port and starboard turns. Only the projection on the attack map is wrong for starboard turns.