Kleiner Nachtrag zum Visier der Martlet. Ich habe dazu folgendes gefunden:
"N-3 Gunsight
N-3C Gunsight with A-2 HeadThe N-3 series of gunsights was by far the most produced and definitely the most widely used AAF gunsight of WWII as it was, at one time or another, fitted to almost every AAF fighter, attack plane, medium and light bomber, but also trainer and even observation plane that needed a fixed gunsight. It was also used briefly as a turret sight at least on B-24’s and probably on Martin top turrets.
The N-3 was definitely not a great and excellent gunsight but it had the advantages of being available (and in great numbers), cheap (3 to 6 times cheaper than the Mark 8 or N-9) and of a size suitable for most aircraft cockpits.
N-3, N-3A & N-3B gunsights were basically N-2A sights with just a few minor differences (see below) and the only big improvement finally came with the N-3C (standardized late 1943) which was lighter (redesigned aluminium casing) and on which the bulb could finally be easily changed in flight in case of failure. Note that the issue of bulb failure in flight was already partially solved before the arrival of the N-3C with the installation of a toggle switch and the new G-9 Mazda double filament bulbs on existing Gunsights. This modification allowed the bulb to use only one filament at a time and if it burned, you just had to switch to the other one.
N-3 (standardized early 1939): similar to N-2A except designed for 24-volt system;
N-3A (standardized early 1941): similar to N-3 except larger opening of reticle holder to permit the use of 70 mil (later 101 mil) reticle and relocation of data plate to the side of the gunsight to avoid light reflection.
N-3B (standardized mid 1942): N-3A with a two wire system and uses a screw-on type electrical connector instead of the push-on type.
The N-3 series also had the distinction of using a great variety of sighting heads (which are a lot of fun of collecting) as, besides standard government procured heads, they were also fitted with a lot of different heads designed and produced directly by aircraft manufacturers. It was indeed the custom in the early years to provide the manufacturers just with the sight and let them design/install their own sight mounts and sighting heads. Some early installations, with the gunsight fixed on the cockpit floor, did not even use any sighting head as the reflector glass was fixed on the back of the instrument or directly on the windshield (P40 B&C for example)."
Quelle:
www.aircraft-gunsights.com/
