SH4 beginners mistakes, unable to torpedo

[jackmchammocklashing]

I have been trying to torpedo ships usually I manage my first target, then nothing at all
In fact my fwrd torps on auto target when 10 degs either side of zero, only show red, and if fired turn about and go astern to infinity hitting nothing

Duh it turned out I was leaving the track target switched on, thus when I was almost alongside the target the track said range 10.000yds not 520
It was tracking my last target set up hours before DUH

Hope this helps another beginner like me