Actually I was replying to the very first post. If you want a lead angle chart, the first one for SH4 was gutted's
However, after stupidly picking the slow speed column for a fast torpedo, I decided that other people could do that as well as I and sought a method that dispensed with the chart. The TDC makes that child's play, as it knows what torpedo you have selected, Mark 14 slow, Mark 14 fast, Mark 18, Mark 27, whatever and computes the lead angle exactly, not even rounded to the nearest half degree. That was the genesis of the true Dick O'Kane method, which always uses the TDC with PK off.