Expected Accuracy of Tiger Triangle Range Finder

[rexford]

The triangles on the Tiger gun sight were expected to be used for range finding, and we did some figuring as to the expected accuracy of the method. Assuming that the gunner wasn't too great with fractions and didn't have a hand held calculator or slide rule, we noted the following:

1. Assuming 3m frontal width works great for a tank facing directly at the Tiger. As the angle increases above 0 degrees the width goes above 3m as side armor contributes to the width:

Tiger looks straight at T34 hull front: 0% error

5 degrees angle: 17% error (actual width is 3.5m)

10 degrees: 33% error (actual width is 4m)

15 degrees: 50% error if assuming front view, 33% assuming side

20 degrees: 18% assuming side and 63% assuming front view

25 to 90 degrees: 0% to 12% error range with 8% average if side view is assumed by gunner

The risk here is that the gunner will assume the wrong facing, such as when a T34 is at 1200m and the angle is 30 degrees but it looks like a front facing. The starting error in that case would be 80%!

2. The second series of tests placed a T34 at 30 degrees to a Tiger and predicted the range that the Tiger gunner would estimate based on the perceived target width. The T34 at 30 degrees angle projects a width of 5.6m, or 5.6 mils at 1000m.

Looking at ranges from 450m to 1200m with 50m jumps, and with the Tiger crew assuming that the T34 was 6m width even though the actual presented width was 5.6m, the range of errors was 0% to 23% with an average of 9%. Accounting for human error might increase the average error to 15%, which is still below the average error of British tankers (20% to 25%).

3. As an example of how the system works, assume the T34 is at 30 degrees angle and is at 650m. The perceived width on the gun sight is 8.6 mils, so the estimated range equals 1000m x 6/8.6 or about 700m.

4. Using the triangles on the Tiger gun sight would appear to result in fairly good range estimates as long as the gunner worked out and rounded the fractions reasonably well, and did not lose his cool, and did not mistake a predominately front view with a side view (in most cases both front and side armor would be presented, but the gun sight distinction between the two might not be especially clear in all cases).

5. The range estimates presented by the Tiger gunner would be given twice the weight of the estimates made by the commander and driver, so the triangles would help to further improve a system which already had many advantages (the Tiger Fibel states that three sets of eyes are better than one, which is statistically true).

6. One problem area is that the T34 is associated with a 3m height, although the T34 M43 appears to have been more like 2.4m.

Done correctly and cooly, the Tiger range estimating system would work much better than the single man methods used in Allied and Russian vehicles.

[Panzer76]

I am just wondering, is it only the Tiger of the german AFVs that used the 3 man estimate procedure, and if so, why?

[rexford]

Originally posted by Panzer76:

I am just wondering, is it only the Tiger of the german AFVs that used the 3 man estimate procedure, and if so, why?

That's a good question that deserves an answer. Right now I don't know but will look into it and maybe some others will as well.

Some of the web sites that deal with the German gun sight make the assumption that the triangle sighting marks were generally used for range estimation. Haven't seen anything on the three man estimating procedure outside the Tiger Fibel.

Thanks for raising an important point.