Expermiting with Scope SH4

[gumbeauregard]

Originally Posted by Rockin Robbins

The time to traverse 10 degrees, even with range known, is insufficient information by itself to hit any target except by pure coincidence. Lacking valid methodology, good luck is your only friend.

The only information required for a zero gyro angle firing solution is the target speed and the torpedo speed. You generate a firing bearing from these two numbers.

The arctangent of the (target speed divided by the torpedo speed) generates the deflection required at any range.

Time to transit X degrees is most useful when firing using sound bearing only in SH4 because there is a gap in sound bearings.

As an example, if I have determined target speed to be 10 knots and plan to fire 29 knot electric torpedoes, I know my deflection is 19 degrees. Firing bearing is 19 (Port AOB) or 341(Starboard AOB) for bow torpedoes.

I close to my planned firing range of 1000 yards.

From my prepared table, I know that the target will traverse 10 degrees at 1000 yards in 31 seconds or about 1 degree every 3 seconds.

When I get a clean sound bearing 20 degrees or less from my firing bearing I note the second hand and do the math to the firing bearing. I fire when the time expires.

If my firing bearing is 19 degrees and I get a clean sound bearing of 25 degrees, I time 18 seconds (3 seconds per degree for 6 degrees) and push the fire button)

The limitations of this, of course, are that the target course must be nearly perpendicular to your line of sight for this method to have accuracy but this fits the minute before firing well.

Dick O'Kane refers to his "seaman's eye" referencing one of Tang's misses where he did not update target speed based on what he saw in the periscope, instead relying on the solution developed by plot and the firing party. His experience determining speed by rate of bearing change is "seaman's eye".

Hard to do in the game but not impossible and, of course, shooting from in close forgives speed errors to a large degree.

If your torpedo does not hit precisely where the wire is at firing then you made a speed error somewhere when shooting zero gyro angle.