Is this a good way to find course and speed?

conura · 07-20-18, 08:50 AM

Hey all,

I've watched quite a few tutorials for how to do this on real navigation/manual tdc and the one that makes most sense to me is to take the range and bearing of a ship, start the timer, then take the range and bearing again in exactly 5 minutes. With this information I have the ships course, and using the distance / time / knots conversion chart the speed too.

With this, I'd then go flank speed, and set myself up ahead of the vessel, submerge, and wait til I have a 90 degree AOB.

I often find the speed is a little off, but this is probably my not being very precise with everything. Is this a good way to get this information? Is this the correct method?

XenonSurf · 07-21-18, 01:32 PM

Fastest and also fairly precise way is to make 2 hydrophone positionings in 5 minutes intervalls and mark everything on the map. You are using your sonarman with this asking him to listen to the closest or to a specific ship. Then you use the calculation tables, those where you can read what's the speed of a ship if it makes x km in y time.
There are other methods ofc.

Cyborg322 · 07-22-18, 09:05 PM

If you want to get a last final speed calculation Using the U-Jagd is probably the best option. Plotting speed over time is good for longer range

You can do it on the fly you just need to time the ship passing from aft to stern thru the scope its useful if the target changes speed at the very last moment you just need an approximation of the ships length . It is surprisingly accurate. I use it most of the time combined with time over distance for long range . Also using the scale which is displayed on the right of the map Knots/Km/Minutes is useful that method just needs a line drawing across the scale from dist thru time the intersection in the middle gives the speed saves working it out in your head

There are few more ways it depends on the scenario and what suits you best some of the more complicated methods don't necessarily give a more accurate calculation. Same applies for AOB and course etc

This is a decent video on the U-Jagd you need TDW's UI or any mod with U-Jagd included. It switches over from the normal stopwatch by right clicking on it

jimmbbo · 07-22-18, 09:32 PM

From Dick O'Kane's method IIRC, I mark the ship's position, start the stopwatch and mark it again 3 minutes later.

Extending the line through the Xs gives the course line, and the ship's speed will be the distance in yards divided by 100... e.g.; in three minutes, if the ship travels 1200 yards, its speed is 12 knots. If it travels 900 yards, it will be 9 kt, or accurately enough for a close in shot.

I then move far enough ahead while remaining at least 5 miles from the target's course to avoid detection, then turn the corner to set up a submerged 90 degree position at 1000 yards from the course line.

Captain_AJ · 07-22-18, 10:42 PM

Quote:

Originally Posted by jimmbbo

From Dick O'Kane's method IIRC, I mark the ship's position, start the stopwatch and mark it again 3 minutes later.

Extending the line through the Xs gives the course line, and the ship's speed will be the distance in yards divided by 100... e.g.; in three minutes, if the ship travels 1200 yards, its speed is 12 knots. If it travels 900 yards, it will be 9 kt, or close enough for a close in shot.

I then move far enough ahead while remaining at least 5 miles from the target's course to avoid detection, then turn the corner to set up a submerged 90 degree position at 1000 yards from the course line.

but .. also consider the sim sh5 IS IN METTERS, READ BERSTERS TEACHING ON WHO TO CALCULATE SPEED .. HUGE DIFFERENCE IN METERS AND YARDS

Fifi · 07-23-18, 02:37 AM

3M 15s between two marks, then the distance in meters gives you the right speed for sure

07-20-18, 08:50 AM	#1
conura Swabbie Join Date: Jun 2018 Posts: 14 Downloads: 38 Uploads: 0	Is this a good way to find course and speed? Hey all, I've watched quite a few tutorials for how to do this on real navigation/manual tdc and the one that makes most sense to me is to take the range and bearing of a ship, start the timer, then take the range and bearing again in exactly 5 minutes. With this information I have the ships course, and using the distance / time / knots conversion chart the speed too. With this, I'd then go flank speed, and set myself up ahead of the vessel, submerge, and wait til I have a 90 degree AOB. I often find the speed is a little off, but this is probably my not being very precise with everything. Is this a good way to get this information? Is this the correct method?

07-22-18, 09:05 PM	#3
Cyborg322 Scurvy Dog of the Deep Join Date: Dec 2009 Location: Manchester England Posts: 1,125 Downloads: 390 Uploads: 0	If you want to get a last final speed calculation Using the U-Jagd is probably the best option. Plotting speed over time is good for longer range You can do it on the fly you just need to time the ship passing from aft to stern thru the scope its useful if the target changes speed at the very last moment you just need an approximation of the ships length . It is surprisingly accurate. I use it most of the time combined with time over distance for long range . Also using the scale which is displayed on the right of the map Knots/Km/Minutes is useful that method just needs a line drawing across the scale from dist thru time the intersection in the middle gives the speed saves working it out in your head There are few more ways it depends on the scenario and what suits you best some of the more complicated methods don't necessarily give a more accurate calculation. Same applies for AOB and course etc This is a decent video on the U-Jagd you need TDW's UI or any mod with U-Jagd included. It switches over from the normal stopwatch by right clicking on it __________________

07-22-18, 09:32 PM	#4
jimmbbo Run silent, run deep Join Date: Jun 2016 Posts: 225 Downloads: 59 Uploads: 0	From Dick O'Kane's method IIRC, I mark the ship's position, start the stopwatch and mark it again 3 minutes later. Extending the line through the Xs gives the course line, and the ship's speed will be the distance in yards divided by 100... e.g.; in three minutes, if the ship travels 1200 yards, its speed is 12 knots. If it travels 900 yards, it will be 9 kt, or accurately enough for a close in shot. I then move far enough ahead while remaining at least 5 miles from the target's course to avoid detection, then turn the corner to set up a submerged 90 degree position at 1000 yards from the course line. Last edited by jimmbbo; 07-22-18 at 10:41 PM.

07-23-18, 02:37 AM	#6
Fifi Navy Seal Join Date: Dec 2012 Location: France Posts: 6,088 Downloads: 466 Uploads: 0	3M 15s between two marks, then the distance in meters gives you the right speed for sure __________________ https://www.mediafire.com/file/rfw2h...N_V7.8.7z/file

07-21-18, 01:32 PM	#2
XenonSurf Sea Lord Join Date: Apr 2008 Location: Germany, Italy Posts: 1,721 Downloads: 107 Uploads: 4	Fastest and also fairly precise way is to make 2 hydrophone positionings in 5 minutes intervalls and mark everything on the map. You are using your sonarman with this asking him to listen to the closest or to a specific ship. Then you use the calculation tables, those where you can read what's the speed of a ship if it makes x km in y time. There are other methods ofc.