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Frederf · 09-22-09, 07:38 PM

I wonder if there's some factors that we're leaving out. There are a lot of assumptions about a target maneuvering to get out of the way of a torpedo.

1. Target spots the torpedo equally well in all directions.
2. Target is able to ascertain torpedo motion well enough to make a fully reasoned maneuver.
3. Target decides what maneuver to make on a case-by-case basis instead of some rapid and wrote drills.
4. Likelihood of torpedo hit overrides all other tactical considerations like defensive posture.

If all Japanese merchants were known to be trained to turn left when under a torpedo attack then that certainly changes your tactics. One might also regard that a target passing through AOB 90 gives the best chance to take good speed, course, etc data for an accurate shot which leaves the submarine aft of beam since the torpedo launch comes after the data taking.

@RR: I'd like to see the same animated .gif with 1 torpedo passing through all 4 targets as if they had a hole in the middle of the ship. That picture is one way I like to attack convoys as several targets' solutions converge.

I have found the AOB150 shots to be more error prone but then again I'm behind a desk and not in a leaky iron warboat 2000mi from home.

As for Cromwell v OKane... they both give about the same leniency to the target to turn a short angle to negate the solution, apart from the time-to-impact difference. I think TTa 90 gives the most difficult evasion scenario for the target but I'm not 100% sure.

Also ArcTan, Inverse Tangent, or Tan^-1 are all perfectly acceptable synonyms. I prefer the Tan^-1 notation when I can actually write the superscript proper unlike in forum posts. I kinda consider the "arc" prefix to be rather anachronistic and to be dropped from high school textbooks steadily.

That chart has an error of either language or trig function. If you want to fire such that the torpedo tracks squarely into the target's side then that isn't a 90 AoB shot but a 90 TTa shot in which case ArcTan is correct. If you want to fire when the target is at 90 AoB (TTa > 90) then ArcSin is correct.

09-22-09, 07:38 PM	#5
Frederf Seasoned Skipper Join Date: Apr 2005 Posts: 665 Downloads: 79 Uploads: 1	I wonder if there's some factors that we're leaving out. There are a lot of assumptions about a target maneuvering to get out of the way of a torpedo. 1. Target spots the torpedo equally well in all directions. 2. Target is able to ascertain torpedo motion well enough to make a fully reasoned maneuver. 3. Target decides what maneuver to make on a case-by-case basis instead of some rapid and wrote drills. 4. Likelihood of torpedo hit overrides all other tactical considerations like defensive posture. If all Japanese merchants were known to be trained to turn left when under a torpedo attack then that certainly changes your tactics. One might also regard that a target passing through AOB 90 gives the best chance to take good speed, course, etc data for an accurate shot which leaves the submarine aft of beam since the torpedo launch comes after the data taking. @RR: I'd like to see the same animated .gif with 1 torpedo passing through all 4 targets as if they had a hole in the middle of the ship. That picture is one way I like to attack convoys as several targets' solutions converge. I have found the AOB150 shots to be more error prone but then again I'm behind a desk and not in a leaky iron warboat 2000mi from home. As for Cromwell v OKane... they both give about the same leniency to the target to turn a short angle to negate the solution, apart from the time-to-impact difference. I think TTa 90 gives the most difficult evasion scenario for the target but I'm not 100% sure. Also ArcTan, Inverse Tangent, or Tan^-1 are all perfectly acceptable synonyms. I prefer the Tan^-1 notation when I can actually write the superscript proper unlike in forum posts. I kinda consider the "arc" prefix to be rather anachronistic and to be dropped from high school textbooks steadily. That chart has an error of either language or trig function. If you want to fire such that the torpedo tracks squarely into the target's side then that isn't a 90 AoB shot but a 90 TTa shot in which case ArcTan is correct. If you want to fire when the target is at 90 AoB (TTa > 90) then ArcSin is correct.