Aldis Signal/Spot Light Kit and Lenses Ref No 5A/823 RCAF 1940-43 KC-97 Here is an early WWII-era

Here is an early WWII-era US Navy aircraft Pelorus Drift Sight

made by the British aircraft instrument manufacturer Smiths

It indicated outside air temperature from -45deg to +45deg C

It appears that they also published technical references and catalogs such as this in an effort to expand their service offerings to their customers

the Avro CF-100 Canuck (see photo of CF-100 instrument panel showing its location)

Aldis Signal/Spot Light Kit and Lenses Ref No 5A/823 RCAF 1940-43 KC-97 Here is an early WWII-eraHere is an original WWII era Aldis Signal Light Kit as used by the Royal Canadian Air Force. The light was used either as a spotlight (by squeezing and holding the large trigger) or as a signal light (by squeezing the small trigger, which altered the angle of the projected light) to transmit Morse code. Atop the light housing is a tubular sight to ensure that the light is aimed at the intended recipient to ensure accurate interpretation of any Morse