P-40 Parts - part 3
by Dan Collier

Attached are some photos of the P-40 bomb-control quadrant, Type L-21A. It was used on all P-40’s that had wing-mounted bombs, except the P-40N-5, which had its own design.

I’ve seen photos of this in the P-40 armament manual and it appears that some quads were cast from aluminum with raised molded part numbers and letters, and others were stamped from steel with stamped numbers and letters, such as this one pictured.

Mine is missing the white-on-black lever selector indicator placard that mounted to the top of this quad for easy reading by the pilot. Mine is shown mounted on its pedestal, Curtiss part number 87-70 638 C.

This assembly mounts directly onto the cockpit floor, which is the top of the wing surface, and to the left side of the pilot seat. This pedestal does not sit flat on a flat surface, but is contoured to fit the curvature of the upper wing surface at the point it is mounted. I hope that your readers will get some use from the photos.

Whenever I see a wartime photo of a P-40, my eyes are always drawn to its gunsight. I’ve noticed that there are two gunsight configurations that usually come up in these photos, and although the P-40’s on an international scale used a few different gunsight models, this article refers to the two U.S. configurations that were designed by Curtiss for their exclusive use on the P-40.

Photo #1 is a photo of Robert Lee Scott posing in the cockpit of his P-40K. It also reveals a perfect profile view of his gunsight: Curtiss’ official label for this is, “Gunsight Assembly 87-69-619”. It places the N-3A or N-3B gunsight body in the horizontal position and uses a 90-degree reflector head. It was used from P-40-D to P-40L models, and in the beginning, this design had no crash pad, and I’ve seen wartime photos where these gunsights had padding materials crudely wrapped around them as a field modification.

This same model gunsight was eventually equipped with the familiar U-shaped rubber crash pad, as used on the other (later) Curtiss-designed gunsight. This (Photo 1) is also the same gunsight that is installed in the P-40E that was recently discovered in the Sahara Desert!

Photo #2 shows a page from the P-40 armorers manual and this is a good view of the second gunsight design that was designed for Curtiss for exclusive use on the P-40’s. This design places the N-3A and N-3B gunsight bodies in a vertical position, and was equipped with a sunscreen that was mounted on rails and a lever on the left side of the gunsight mounting yoke would raise and lower the green sunscreen over the clear reflector glass. This entire sunscreen and rail assembly was made of plastic, and sometimes discarded in the fields. This gunsight also had a U-shaped crash pad. The early crash pads were upholstered, while most were a form of molded rubberized material. This gunsight was used from the E models and up to the N models and Curtiss designated it, “Gunsight Assembly 87-69-964”. Both gunsight designs were used by the same P-40 models up to the L models, and I cannot tell you what would determine which individual plane got which gunsight.
But sometimes you’ll see one gunsight model in a P-40E, for example, and at other times you’ll see the other in an E.. Or F, etc.

Photo #3 AND #4 show recent photos of both gunsights next to each other for comparison..They also include their mounting yokes, attached to the N-3 gunsight bodies.

Photos #5 and #6 show both gunsights installed in a P-40E panel. Both are very rare today, and the horizontal one shown in Robert L Scott’s cockpit is by far the most rare. It took me 42 years to find one! Modelers usually install the vertical design sight in their models, but I’ve only seen one scratch model using the horizontal design with 90-degree reflector head. This is probably because very little is known about the horizontal designed gunsight, and because most wartime photos don’t give much detail on either model.

Photos #7 and #8 are nice photos as well. #8 makes the gunsight look oversize because I was too close to it when I took this photo. Sorry ‘bout that!

Because less is known about the horizontal gunsight with 90-degree head, I’m attaching more random photos to show it from more angles. Photo #9 shows a nice profile shot, and Photo #10 shows the N-3A placard positioned at the top of the gunsight and this caused complaints from the pilots about the reflective glare that this caused to their front windscreen panel. This placard was then relocated to the side of the gunsight body to eliminate the reflective glaring problem..

Photo #11 shows the horizontal gunsight illuminated image as seen through the 90-degree reflector head.

Photos from #12 to #16 are more random photos.

© Dan Collier 2014