Determining speed without map contacts

[Bubblehead1980]

So I have been away from SH 4 TMO for a while, just been too busy with RL to play but found sometime recently.I have played on 100 realism for a while and enjoy it but have found myself having some trouble firing torpedos accurately without map contacts.Usually I estimated speed via sound reports and visually by things such as bow wake etc and had very high number of hits/sinkings, mostly from playing enough.I am now somewhat out of practice and wont be playing enough to get back to my previous level.

So my question is, what are some methods to determine speed without map contacts turned on? with map contacts on its easy to get speed, mark a spot, wait 3 minutes, mark current location of target, then measure distance, 900 yards= 9 knots.

Tried marking positions on map without contacts but didnt work out too well, too many misses.So any suggestions on how to get speed for a "traditional" TDC shot? not looking for the trick shots some use, i prefer to do it how it was done, not finding AOB or distance difficult without contacts, just speed.Thanks in advance.

[razark]

One method I've used: http://www.subsim.com/radioroom/showthread.php?t=112765
If you've got a couple of bearing and range observations, and the time between them, it give you everything you need.

[Rockin Robbins]

Well if you aren't finding distance difficult, then speed is a done deal. You need two positions (bearing and range) plotted three minutes apart. The distance between them in hundreds of yards is the target speed.

If your speed isn't working out then you have a problem measuring distances.

[raymond6751]

Draw your own line.

First identify your target type. Check the ship manual for the speed indicated (normal) for the type.

Create your own line with the ruler that would be the distance it would move at that speed, in a given time.

Watch if he reaches the end of your line in the expected time. Early and he is going faster, longer and he is going slower.

It is a guess.

[Fish40]

The way I find speed is as follows: Time how long it takes the ship to cross the 0 bearing line on the scope. You will need to ID the target because you need it's length ( there is a mod out there that adds ship lengths to the RM). Once this is established, useing some basic math gets you your speed. I find this method not only pretty accurate, but a challenge since you need to correctly ID the target or your calculations will be off. Don't forget, timeing a convoy is simple since once you establish the speed for one of the ships, you have the speed of the convoy. Practice makes perfect!

[Rockin Robbins]

Yes, the time it takes the hull to cross the wire works. However, if you're taking all the trouble to be authentic, which is impossible as you give up more authenticity by turning map contacts off than you do by leaving it on, you must also be aware that this method of determining ship speed is totally inauthentic.

We have a target manual that contains every ship on the ocean. The real subs' targeting manual was a travesty. Most targets sunk during the war were grossly misidentified as to identity, tonnage, and length. Therefore, even if they used this method, which they did not, it would have yielded grossly wrong speeds.

No matter how we twist things this is a game. We roll the dice and play it the way we like because........we like it that way! Any arguments about authenticity quickly become jokes as each choice has the intended consequence, then drags along three unintended consequences, making the game even less realistic.

The map contacts on/map contacts off deal is one of those. If you're running TMO, there is only one inauthentic part of the plotting: targets which are visual only are plotted with exact position. In order to kill that you have to kill radar positions, plotting of sonar lines, airplane radar......it's a quagmire that just doesn't justify fixing one element to ruin three or four others.

If you were on a boat with radar, you would actually know the positions of the targets to greater accuracy than the game is allowed to show because of position binning (you have a choice of a dot here or here, not in between on a digital display) and the range readout on real WWII radars, which we do not have.

If you think it is more authentic to keep map updates off (or if not for that matter!) there is no way you can justify the timing of ships across the wire using their length to calculate speed. In WWII that just wasn't possible.