How to zero out the TDC?
 

You've been tracking a convoy, and filling the TDC with data. But now you don't like the original target as much as another. There is no time to bother with the TDC; you just wish to point and shoot.

How do you zero out the TDC so that torpedoes fire with no gyro at bearing 0? The only method I've worked out is to save and reload; surely there is another?

Thanks much.

Edit: I'm using SH 1.5 with TMO/RSRDC, if it matters. And manual targeting.

Unlock TDC , set speed to zero, set a new bearing, shoot and hope you get lucky...course you'll have to guess where to shoot based on his speed, it's a crap shoot at best and you have just as much time setting up a new TDC plot...if you don't have time for speed, look at the bow wake and guess.

Make sure the PK is off, point your scope to Bearing 0, set speed to 0, move the stadimeter a bit, click Send. You're done.

ah, move the stadimeter! Perfect, thank you.

I've worked out a quick firing method using the sonar call-outs on bearing. If the target is moving @ 7 knots, and my Mark 10 torpedoes move at 36 knots, then the correct firing angle is 11 degrees. So, I fire when bearing reaches 11 degrees of center (11, or 349, depending on whether target comes from left or right). Or perhaps a bit sooner, if I wish to lead the target and fire a spread.

The tricky part is to line up as close to 90 degrees on the beam as possible. Range is irrelevant up to torpedo range, as long as they have time to arm.

After a few patrols I've basically memorized the correct firing angle for various common target speeds.

Probably this is similar to the O'Kane method; I'm not sure. But it's quick, and immune to corrupt stadimeter readings....

Vector Analysis. Both the O'Kane and the John P. Cromwell attack methods are derivatives of it. You can fire from any angle, the basics are the same. Rockin Robbins has made a handy, printable crib sheet of all three methods here.

Yea, a basic 90 degree Okane, but you do have to set it up, sometimes I do shoot down a zero bearing guessing not worried about the angle, but it's just to get off a quick shot and is usually when I'm attacking a large 30 plus ship convoy with many overlapping targets.

With speed set zero and bearing set zero, you have to make sure there is a non-zero value for range or the TDC freaks out and your torpedo goes wacko. It's a computer thing, not a real TDC thing: a defect in programming the modern PC. It doesn't matter whether you get this range from fiddling with the stadimeter or fiddling with the TDC input dials.

The TDC was a computer too, you know!:D

Clear the Bridge
 

I'm in the middle of reading O'Kane's "Clear the Bridge!'. Very cool. It makes you appreciate the skills involved regarding shooting as well as plotting, diving (trim etc). I wasn't aware there was an 'art' to trimming the boat but it certainly comes across in his book. The length of time spent in getting into attack position is also an eye-opener. Highly recommend.