does the TDC account for the turning of the sub?

[Schwuppes]

Hi!

Basically if I set up the AOB and speed and then lock on the target can I turn my boat and the AOB will still be correct?

For example:

Lets assume I have a target at bearing 270° (doing 0 knots) with an AOB of 90° starboard.

After entering this information into the TDC can I lock on to the target, turn my sub by 90° to port (so that the target is now at bearing 0°) will the AOB then still be 90°?

Will the TDC take into account that its actually my own sub has turned/moved, and not the target?

cheers!

[Platapus]

AoB is independent of the heading of your submarine.

AoB is the angle formed by the heading of the target ship and your submarine.

The heading of your sub does not figure into AoB but the heading of the target ship does.

The bearing from your sub to the target ship does not factor into AoB.

The bearing from the target shop to your sub does.

Did I explain that clearly?

AoB is tricky to understand

[joegrundman]

Whatever Platapus meant to say, the answer is no. Assuming you have once set up an accurate AOB solution it will remain accurate (except for range) so long as NEITHER you nor the target change course. (Also target speed can change if playing GWX, but this won't affect the AOB solution) Range will of course become out of date, but i have come to the conlcusion that this is rarely a disadvantage.

If you change course the automatic AOB solution will not be accurate any longer and you will need to input a new AOB solution. This is because the Relative Course of the target is a function of BOTH AOB and Relative Bearing to target.

If you change course, although the true AOB won't change, the relative bearing to target will. If your TDC is on auto update while you change course, then the AOB will be inaccurate by the number of degrees you changed course. You need to reinput AOB data after a change in course.

It is also possible, if you are skilled at manually handling the TDC, to set up the system in advance for the course that you WILL be on after you have adopted a firing position.

joe

[Schwuppes]

thanks guys!

Platapus, I know how AOB works, but thanks anyway! :)

Thanks for that answer joegrundman!

hmmm... that got me thinking..:hmm: Would it have been possible to design the TDC in a way that allowed the "AOB system" to be linked to the compass heading/course.

I.e a change in compass bearing would cancel out a change in relative bearing to the U-Boat in order to maintain the correct target AOB?
Basically the TDC AOB would subtract any change in true course from the AOB and apply it to the AOB wheel?

For example if my current compass heading is 0° north, the target bearing is 90° (which would obviously also make its true bearing 90° (east)) if I then turn 90° to the right towards it so the bearing is 0° the TDC would just have to subtract 90° from 180° which would mean it maintains the correct AOB.

But then the TDC would have to be linked to the rudder system so "it knows" if the boat is turning to port or starboard right?

Sorry its difficult to explain for me... I hope its makes sense :D

[joegrundman]

Was it possible using the technology of the day, you mean? Sure, the American TDC could process changes in your own course and speed and factor in the changing range to target too. However, while this was no doubt an exceedingly clever device, it could be argued that in some ways it was not as useful for its job as the much simpler German TDC.

However, I have also heard that in reality the GErman TDC did not have an AOB dial, it had a true course dial - which implies it is dependent on knowing the U-boats true course. If so then it should have been able to take into account changes in the U-boat's course.

But I have never come across a clear picture of the german TDC, nor do i know how many versions there were and how they differed

[Antiacus]

Hmmm. I believe the whiz wheel updates since it changes with your course changes... Correct?

I guess that's assuming you're using OLC GUI (why wouldn't everyone?).

[Pisces]

However, I have also heard that in reality the GErman TDC did not have an AOB dial, it had a true course dial - which implies it is dependent on knowing the U-boats true course. If so then it should have been able to take into account changes in the U-boat's course.I don't know about the TDC, but if you can read german (see the 'Peileinrichtung' link on) the following website says some types of periscopes had a true bearing dial corrected for sub movemet by means of a differential gear system. So it gave directions relative to north. Since sub-course was provided by a gyro-compass device I see no reason why it could not have been fed into the TDC device just as simple. Electrically or mechanically.

(be CAREFULL, there has been reported a virus warning by a member here when he accessed that site, make sure your system is impervious)

http://www.uboot995.homepage.t-online.de/index.htm/Sehrohre_u__Zubehor/sehrohre_u__zubehor.html

I hope some german speaking member can translate these texts. Because I s*ck at translating german language.