Unknown RPM Indicator 6a/1134

[bananamafia]

could anyone shed any light on this little beauty?
6a/1134
unfortunately its not dated.
any ideas on what aircraft its for?

[Air Ministry]

It's a B.T.H. instrument of the type fitted to (for example) the de Havilland Dominie (Dragon Rapide).

[Jim]

It is not from the Great War era, it is from the WW2 era. It is an instrument that measures the speed of the engine in revolutions per minute. This one is British and would have been used by the RAF on the instrument panel of a number of different aircraft. Given the range of RPMs (revolutions per minute) this would likely have been used on one of the many different aircraft that used a Gypsy Major engine, or another engine of the same power ratings. It is not possible to tell what kind of aircraft specifically since these were one size fits all instruments for all aircraft that used engines of this general type. When they broke, they were removed, and another was installed to replace it. The broken instrument would have been sent for repair to one of the RAF repair centers and from there it would be returned to stock for someone else to requisition to install in some other aircraft that needed such a gauge with this range. The 6A/ is the clue that says this is Second World War and not Great War. 6A was the Air Ministry's code for aircraft instruments. The numbers to the right of the / mark indicate which specific instrument. There is a manual that lists all of these "Stores Numbers" but I do not have it. These types of WW2 aircraft instruments are quite common and can be had for very little money on Ebay and other places, but I think they are interesting relics of WW2. Some collectors like to get old instrument panels and collect the instruments that would have been appropriate to that particular aircraft, mount them in the panels, and show them as recreated instrument panels. The aircraft instruments that are less common and command better prices are the ones from the Great War. Also there is a bit of a hierarchy to instruments with the more major ones such as Air Speed, Altitude, Compasses and Clocks getting the best prices with less important gauges such as RPMs, engine temperature, slip gauges, fuel, and the like getting less. For more information on your instrument my recommendation would be to ask your question on a WW2 forum rather than this one since this one is limited to discussions on the aviation aspects of the Great War.