How do you shadow/attack a convoy?

[Loud_Silence]

I've only been able to truly shadow convoys after getting the improved surface search radar. Earlier in the war i would just pick a radio report, move in front of it, and pray so the convoy didn't change its course.
I also attack at surface very, very often. Even in complete darkness, i was spotted by a freighter about 3000 yards away. I attack at surface only for long range targeting practice (I have to fire my torps up to 4000 yards away, to make sure i'm not spotted, and i NEVER attack a convoy at the surface).
For attacking convoys, i shadow the convoy, place myself before on its path and wait, sink one or two ships if i can and then I evade the escorts and set another attack or just get away.
I fire from about 3500 yards from the center of the convoy to stay away from the flank escorts, so in case i'm detected i have some time to dive. But i've heared stories about skippers attacking from 1000 yards... At that distance, even if the escorts don't detect you, they will end up running into you because you're practically in front of them...
And of course, i have god's eye mode on. If i can't make multiple shots with it on, hitting a single ship is almost impossible for me...
But i've heared about skippers attacking convoys while moving, estimating AoB just by eyeball, shadowing a convoy on visual range EVEN DURING DAYLIGHT...
I'm currently running 1.5 with no adons or mods. Im just in January 1945, so this campaign will end soon. But after finishing this one, i want to start another, with realism at 100% and some realism mods. Could you recommend any, please?
Any advise about convoy tactics?
Thank you
And sorry for my bad english

[Hitman]

But i've heared about skippers attacking convoys while moving, estimating AoB just by eyeball, shadowing a convoy on visual range EVEN DURING DAYLIGHT...

Both americans and specially germans did that easily prior to escorts getting radar. The problem in the game is that your visibility is limited to some 20 kilometres, and that isn't always enough to do it as in real life: Keep the enemy under the horizon while only seeing the tips of their masts, never getting closer.

Nevertheless, if you want to read about real life tactics go here:

German U-boats: http://www.hnsa.org/doc/uboat/index.htm

US submarines (Post-war but reflects war tactics): http://www.hnsa.org/doc/attack/index.htm

[Wicked Popsicle]

Some really cool links saved in my favorites to review later

[gimpy117]

I do the race ahead and wait tactic....if your careful...go to silent you might be able to stay at peri depth and get within 1,000 yards. If some destroyers start moving fast toward you or are on a course taking them within 1,000 yards you might wanna get outta there because there's a solid chance of detection and the ramming will commence...

Originally Posted by gimpy117

I do the race ahead and wait tactic....if your careful...go to silent you might be able to stay at peri depth and get within 1,000 yards. If some destroyers start moving fast toward you or are on a course taking them within 1,000 yards you might wanna get outta there because there's a solid chance of detection and the ramming will commence...

The end around. That is my tactic of choice as well. I'll get infront of the convoys plot, use the ruler to get an idea where the center of the convoy will be passing, then park myself slightly off of that line. If there are a lot of escorts I'll dive deep and wait for the escorts to pass before popping back up to PD.

Depending on my torp situation I'll either set myself up for bow or stern shots to try and keep from emptying one room and leaving the other full. You never know when you'll need to DTT a DD.

[Morpheus]

sometimes DDs are going infront of the convoy you are waiting for submerged. go below the thermal layer (engines stopped), let the DDs run over you, come up again behind them, and start your torpedorun ...

[Rockin Robbins]

Although a real sub could float on top of the thermal layer with engines off, they couldn't lurk below it. Because of currents and the constantly changing density of the surrounding water, hovering a submarine with engines off was impossible for any length of time over a couple of minutes. Even that was nail-bitingly difficult. However, they could control buoyancy well enough to sink in the warm layer while floating in the denser cold layer underneath and sit there with power off for hours.

[Loud_Silence]

Then, in real life, waiting in front of the convoy was impossible?

[Morpheus]

silent running then, to maintain depth.