10th Patrol of U-53 - Radio Contact Intercept

[Canovaro]

A nice intercept!
It's always nice if a plan comes together with or without the mobo (don't use it myself).

I have one comment though. A lone ship is always reported with speeds like slow or medium, unless BdU gives another contact report (like in your case).
This is the weak point of any calculation. You took 6 but the range could have been 4-7 or even greater.
What I do is calculate the position with a range of 7.5 when reported slow and then just wait for it. It's a bit dissapointing if it's much slower, but better than missing it altogether.
With convoys, you can always read the exact speed from the contact report...
There are a couple of other considerations as well. The contact report seems to be from 14:50. It is now 14:53. That's hardly any difference, but nexttime it may differ half an hour. It's just a matter of how quick you can get out of time compression.
You also don't want to cross the target's path literally, because it can spot you an start zig-zagging. you want to lay and wait submerged. The range of view depends of the time of day, the wind speed and fog. I would say it's max 7000 meter

I have made the convoy intercept 'theory' below which is based on some other basics that you can find on this forum, but has these things included in the calculation.

[XLjedi]

I actually used MoBo pretty sparingly on this one... I thought some folks might like to see how easy it is to calibrate the TDC without a lot of complex measurements or AoB guesstimates. I spent zero time on visual observations. I was setting up the TDC before I ever saw the target.

Originally Posted by Canovaro

I have one comment though. A lone ship is always reported with speeds like slow or medium, unless BdU gives another contact report (like in your case).
This is the weak point of any calculation. You took 6 but the range could have been 4-7 or even greater.

For a "slow" report I'm pretty successful with 6. Setting it for 7 does usually give you some cushion. I wouldn't set it higher than 7 for slow.

Originally Posted by Canovaro

The contact report seems to be from 14:50. It is now 14:53. That's hardly any difference, but nexttime it may differ half an hour. It's just a matter of how quick you can get out of time compression.

How fast you click TCx1 actually doesn't matter at all. In this case, I was pretty nimble, but sometimes I can be off by 30 mins. In which case I would just advance the target position for distance travelled in 30 mins by means of dead reckoning. Your intercept calculations are then based off the proper time adjusted position.

Originally Posted by Canovaro

You also don't want to cross the target's path literally, because it can spot you an start zig-zagging. you want to lay and wait submerged. The range of view depends of the time of day, the wind speed and fog. I would say it's max 7000 meter

Rather than submerge and wait, I like to submerge and stay on the advance...

Notice I did submerge well beyond visual range. The first time the target had any chance to spot me was when I peeked the scope out of the water at 1500m and had the ship in my sights at a bearing of about 25°. At which point, I was opening tube 1.

Generally speaking, I try to station myself such that I can make the final approach submerged at 4kts regardless of which direction I'm coming from. So I try to intercept a station for a 4kt approach... not necessarily the direct method. As I mentioned, the initial stationing of this intercept is my favorite starting point because it decreases my workload by not having to plot an appropriate end-around.

Originally Posted by Canovaro

I have made the convoy intercept 'theory' below which is based on some other basics.

Appears reasonable... The intercept was based on how I like to do it; but that was only half the story here. The other message I wanted to get across in this report is how easy it is to get started in manual targetting by choosing your attack position. In which case, all of your TDC dial settings are known.

That circle diagram you posted is pretty clever... I like it.

[Canovaro]

Originally Posted by =aaronblood

Rather than submerge and wait, I like to submerge and stay on the advance...

Notice I did submerge well beyond visual range. The first time the target had any chance to spot me was when I peeked the scope out of the water at 1500m and had the ship in my sights at a bearing of about 25°. At which point, I was opening tube 1.

Generally speaking, I try to station myself such that I can make the final approach submerged at 4kts regardless of which direction I'm coming from. So I try to intercept a station for a 4kt approach... not necessarily the direct method. As I mentioned, the initial stationing of this intercept is my favorite starting point because it decreases my workload by not having to plot an appropriate end-around.

I think both methods are equally effective.
I would proceed on the surface with higher speed and then dive at the final point. You would stay on the run while submerged the last part.

Originally Posted by =aaronblood

Appears reasonable... The intercept was based on how I like to do it; but that was only half the story here. The other message I wanted to get across in this report is how easy it is to get started in manual targetting by choosing your attack position. In which case, all of your TDC dial settings are known.

I think you made your point well! It's a good step-by-step.

That circle diagram you posted is pretty clever... I like it.

The circle diagram itself is not my idea...it comes from Dantenoc afaik

[looney]

So for a slow contact speed is between 4 and 7?
medium 8 and 10 and for fast anything faster than 10? am I right?

[XLjedi]

Originally Posted by looney

So for a slow contact speed is between 4 and 7?
medium 8 and 10 and for fast anything faster than 10? am I right?

I like...

6 or 7 for slow (I favor 6)
8 or 9 for medium (I favor 8)

...and I've been guessing 16 at fast and haven't had much luck. Any recommendations there would be welcomed.

[Canovaro]

Originally Posted by aaronblood

I like...

6 or 7 for slow (I favor 6)
8 or 9 for medium (I favor 8)

...and I've been guessing 16 at fast and haven't had much luck. Any recommendations there would be welcomed.

Fast can only be a tanker or a warship afaik.
A tanker I would guess 10 or 11.
Warships can be anything between 9 and...35? 40? I don't know.

[XLjedi]

Originally Posted by Canovaro

Fast can only be a tanker or a warship afaik.
A tanker I would guess 10 or 11.
Warships can be anything between 9 and...35? 40? I don't know.

Yeah I've also seen lone cruise ships hummin along at 16, but you're right about the tankers. Probably good guess for the Type IX cap'ns cruisin the Carribean.

When I've seen "task force" as the contact plot I've tried 16 and I haven't had much luck with that guess. Maybe 22? I think part of the problem is the blasted things are turning pretty tight patterns.