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Hitman · 03-13-10, 04:27 AM

OK, let's see if I can clarify this once and for all

The construction of a firing solution is based upon a firing triangle. That triangle is made up of three corners, which are:

1) Target
2) Torpedo (And not our uboat, because we want the torpedo and not our sub to collide with the target, you know)
3) Intersect point between torpedo and target tracks

Three corners are three angles, and all three of them are represented with dials in the TDC. You only need to know where to look for them.

What we will input into the TDC is:

Dial 1) Target position: Automatically done by training our optics to the target. That's the bearing from OUR submarine, but not from the torpedo (Which is some 30 metres forward of the periscope/uzo in its tube). But the TDC will automatically correct that by calculating the parallax, based on the distance to target we input (Dial nº 4). This is measured with two black dials side by side, one for 0-360º (As in our periscope/UZO) and another with 0-10º that acts as vernier.

Dial 2) Target course: Manual input of the Angle on the Bow by us. Will be shown in the red/green dial (0-180º at each side) with a small vernier inside.

Dial 3) Note that we will NOT input the third corner of the triangle, i.e. the corner at which torpedo and target will come together and collide. The reason is that any triangle's angle can be calculated as long as we have the value of the other two angles, and the TDC will do it for us and show the result in the Track Angle (Auftreffwinkel) dial. Again it will be shown in a dial divided in green/red with 0-180º scale at each side.

NOTE NOW THAT BOTH DIALS THAT ACTUALLY HAVE DATA RELATING TO TARGET GEOMETRY ARE DIVIDED IN GREEN/RED. Whereas dials referring to own Uboat data are black, in 0-360º divisions. Why? Because sitting in our uboat we have a 360º view around, but when looking at the target we will see either side of it, the front or the rear. Never a full pan around.

Now, the output of the TDC, i.e. the result for the firing solution, in short: How much the torpedo must turn right or left after leaving the tube, in order to get into a collision course with the target, is the Gyro Angle, indicated in the very same centre of the TDC by two dials. Again, because the torpedo is in OUR Uboat, the dials are one for 0-360º and another with 0-10º that acts as vernier.

The TDC will also tell us the torpedo run until reaching the target, so that we can see if it is in reach, and estimate the seconds to impact.

A scheme of the firing triangle:

And how it looks like in the TDC: (The three corners are connected with green lines to make the firing triangle easily visible):

03-13-10, 04:27 AM	#131
Hitman Pacific Aces Dev Team Join Date: Sep 2002 Location: Spain Posts: 6,109 Downloads: 109 Uploads: 2	OK, let's see if I can clarify this once and for all The construction of a firing solution is based upon a firing triangle. That triangle is made up of three corners, which are: 1) Target 2) Torpedo (And not our uboat, because we want the torpedo and not our sub to collide with the target, you know) 3) Intersect point between torpedo and target tracks Three corners are three angles, and all three of them are represented with dials in the TDC. You only need to know where to look for them. What we will input into the TDC is: Dial 1) Target position: Automatically done by training our optics to the target. That's the bearing from OUR submarine, but not from the torpedo (Which is some 30 metres forward of the periscope/uzo in its tube). But the TDC will automatically correct that by calculating the parallax, based on the distance to target we input (Dial nº 4). This is measured with two black dials side by side, one for 0-360º (As in our periscope/UZO) and another with 0-10º that acts as vernier. Dial 2) Target course: Manual input of the Angle on the Bow by us. Will be shown in the red/green dial (0-180º at each side) with a small vernier inside. Dial 3) Note that we will NOT input the third corner of the triangle, i.e. the corner at which torpedo and target will come together and collide. The reason is that any triangle's angle can be calculated as long as we have the value of the other two angles, and the TDC will do it for us and show the result in the Track Angle (Auftreffwinkel) dial. Again it will be shown in a dial divided in green/red with 0-180º scale at each side. NOTE NOW THAT BOTH DIALS THAT ACTUALLY HAVE DATA RELATING TO TARGET GEOMETRY ARE DIVIDED IN GREEN/RED. Whereas dials referring to own Uboat data are black, in 0-360º divisions. Why? Because sitting in our uboat we have a 360º view around, but when looking at the target we will see either side of it, the front or the rear. Never a full pan around. Now, the output of the TDC, i.e. the result for the firing solution, in short: How much the torpedo must turn right or left after leaving the tube, in order to get into a collision course with the target, is the Gyro Angle, indicated in the very same centre of the TDC by two dials. Again, because the torpedo is in OUR Uboat, the dials are one for 0-360º and another with 0-10º that acts as vernier. The TDC will also tell us the torpedo run until reaching the target, so that we can see if it is in reach, and estimate the seconds to impact. A scheme of the firing triangle: And how it looks like in the TDC: (The three corners are connected with green lines to make the firing triangle easily visible): __________________ One day I will return to sea ...