Rater of Climb / Vertical Speed Indicator, Pre-WWII WW1 25 inches diameter and ~2

25 inches diameter and ~2 inches deep

The drum can be removed and the chart replaced as needed

This WWII-era bound edition of the US Army Air Force's Gunners Information File consists of several separate WWII-era manual publications combined into one hardback volume

It is new old stock

this was used in the reconnaissance aircraft Fieseler Storch Fi 156

Rater of Climb / Vertical Speed Indicator, Pre-WWII WW1 25 inches diameter and ~2This is an early Pre WWII era Rate of Climb Vertical Speed Indicator, measuring climb or descent up to 2,000 ft per minute. Made by Pioneer, part number 321 1177. At 2. 75 inches diameter, the face is smaller than WWII era indicators. It is ~3. 5 inches deep. The glass is clear and the markings are superb.