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Markus Witt · 08-29-19, 08:25 AM

This is a historical method explained in detail in below thread:

https://www.subsim.com/radioroom/sho...dampfverfahren

Basically with this method you adjust your course and speed to obtain a constant bearing (collision course) to your target. With this constant bearing it is very easy to find a firing solution through some mathematical trickery. Advantage of this method is that you do not need to know the target's speed, course AOB or range.
All you need to do is calculate the speed input for the TDC. This speed is calculated with the formula: own speed * sin (relative bearing to target).
This calculation can be done very quickly with the slide rule.

For example: your own speed is 11.2 knots and you maintain a constant bearing of 327 (relative bearing of 33 degrees to port) to your target.
To find the TDC speed point the 1 on the C scale to your own speed (11.2) on the D scale. Now put the hairline over 33 degrees on the S scale. The TDC speed can now be read under the hairline on the D scale (6.1 kts). See photo.

08-29-19, 08:25 AM	#5
Markus Witt Navy Dude Join Date: Jul 2010 Location: AN8563 Posts: 171 Downloads: 309 Uploads: 0	Ausdampfverfahren This is a historical method explained in detail in below thread: https://www.subsim.com/radioroom/sho...dampfverfahren Basically with this method you adjust your course and speed to obtain a constant bearing (collision course) to your target. With this constant bearing it is very easy to find a firing solution through some mathematical trickery. Advantage of this method is that you do not need to know the target's speed, course AOB or range. All you need to do is calculate the speed input for the TDC. This speed is calculated with the formula: own speed * sin (relative bearing to target). This calculation can be done very quickly with the slide rule. For example: your own speed is 11.2 knots and you maintain a constant bearing of 327 (relative bearing of 33 degrees to port) to your target. To find the TDC speed point the 1 on the C scale to your own speed (11.2) on the D scale. Now put the hairline over 33 degrees on the S scale. The TDC speed can now be read under the hairline on the D scale (6.1 kts). See photo. Last edited by Markus Witt; 10-26-22 at 02:05 AM.