Found the gunsight and gun harmonizing manual for all AAF aircraft up to 1944. In it the reticles are described for the N-2, N-2A, N-3A, and N-3B. I cross referenced that against the AAF document of Installation and Inspection for the N-2, N-2A, N-3, N-3A and N-3B. The N-2 was the standard gunsight for the AAF from 1936 and into the war.
Note: N-2A and N-3 are the same gunsight. Both use a Ladder reticle. A ring and dot reticle did not come into common use until the N-3A. References to an N-2C like modeled in our P39-D are related to the sight head being longer than in the N-2A sight head and I have only ever seen a drawing in: "British Aircraft Armament Vol.2: Guns and Gunsights", by R Wallace Clarke.
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From the War Department Technical Manual TM-495, 11-8-44:
"The types N-2 and N-2A sights have an image consisting of three horizontal lines divided by a vertical line."
"The top line of the three horizontal lines represents a point to be used at 200 to 500 yards. The next two lines represent points to be used from 500 to 1000 yards and 1000 to 1500 yards respectively."
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Early on in the development of reflector or collimating gunsights by the US Army, the closest experience to such a sight were the optical sights in vehicles like the M8. The P39 and it's M4 37mm cannon were treated like a flying artillery stand and so the ladder reticle. It was used as a bombing aid in the P39D and some P40.
In our game the only N-2 gunsight is in the P39D. Since there is not sight head on the gunsight in the floor of our P40-C, nor a material identification plate, I cannot tell which type HTC modeled.
The NAVY in 1941 mounted a modified N-2A, N-2AN into F4f-3 with a 35mil ring and dot reticle to allow for lead shots. They were phased out quickly as the Mk8 became available.
Set your 37mm to 400 and the lines in the ladder are 200-400, 500-800, 1000. Shooting past 1000 in the game is a Hail Mary. Very quickly you will see how little experience the US Army at that time had with air to air combat related to collimating gunsights. The boarders of the lines represent a 2 inch optical viewing area or approximately 100Mil. Works well for de-acking and shooting at fixed ground targets with the M4 cannon. Offline practice will help since this is an aid and not a point and click device.
N-2 Ladder Reticle
Copy both the (bmp) and (mil) file to your sights directory or the sight will show up too small. If you get the two popups clicking on the download, just kill their windows with the red X button and ignore them.
Download Link ===>> http://www76.zippyshare.com/v/65999405/file.html
