Air Ministry Ammeter

We have looked at various military electrical gauges over the years and tonight we have a small example of an RAF ammeter:imageThis gauge is different from previous examples we have covered due to its small size and four mounting holes in either corner of the square face. This suggests that this particular ammeter is taken from an aircraft rather than being for some ground based purpose.

The front face of the ammeter is marked with the AM and crown mark of the Air Ministry and a stores code of 5A/1663:imageI have tried looking up this code and come across several eBay auctions describing this as being a ‘rare early Spitfire instrument’. Unfortunately I cannot find any corroborating evidence for this description yet and sellers are notorious for trying to attach militaria to an interesting unit, person vehicle in a bid to boost sales. A list of Air Ministry stores codes however suggests that it is actually for ground lighting and miscellaneous equipment:

Air Ministry Equipment Codes:

4A = Workshop Equipment
4C = Airfield Equipment
4F = Air Compressors and Servicing Trolleys
4G = Aircraft Servicing and Ground handling Equipment
4K = General Ground Equipment (including Refuelling Equipment)
4N = Sparking Plug Testing and Servicing Equipment
4FZ = Air Compressor Spares

5A = Ground Lighting and Miscellaneous Equipment
5B = Aircraft Wiring Assemblies
5CW = Aircraft Electrical Switches, Switchboxes, Relays and Accessory Items
5CX = Aircraft Electrical Lamps, Indicators, Lampholders and Accessory Items
5CY = Aircraft Electrical Plugs, Sockets, Circuit Markers, Suppressors and Accumulator Cut-outs
5CZ = Aircraft Electrical Miscellaneous Stores
5D = Aircraft Armament Electrical Stores
5E = Cable and Wire Electrical Stores
5F = Insulating Materials Electrical Stores
5G = Special Ground Equipment
5H = Standard Wiring System
5J = Batteries Primary and Secondary
5K = Electrical A.G.S and Bonding Stores
5L = Electric Lamps
5P = Ground Charging, Transforming Equipment and Motors
5Q = Ammeters, Micro-ammeters, Milli-ammeters, Voltmeters and Milli-voltmeters
5S = Strip Wiring Components
5UA = Aircraft Engine and Air Driven Electrical Current Producing Equipment and Spares
5UB = Aircraft Electrically Driven Electrical Current Producing and Transforming Equipment and Spares
5UC = Aircraft Electrical Current Control Equipment and Spares
5UD = Aircraft Electrical Motors, Blowers and Spares
5UE = Aircraft Electrically Driven Pumps, Accessories and Spares
5V = Aircraft Electrical Domestic Equipment
5W = Aircraft Electrical Actuators, Accessories and Spares
5X = Component Parts of Wiring Assemblies

6A = Aircraft Engine and Flying Instruments, Accessories and Spares
6B = Aircraft Navigation Equipment, Accessories and Spares
6C = Instrument Test Equipment, Tools, Accessories and Unit Equipment Spares
6D = Aircraft Gaseous Apparatus and Ancillary Equipment
6E = Miscellaneous Instruments, Accessories and Unit Servicing Spares
6F = Aircraft Personnel Equipment
6H = Aircraft Automatic Pilots, Marks 4 and 8, Major Components, Servicing Spares and Tools
6J = Aircraft Automatic Pilots, Types A3 and A3A and A.L.1, Major Components, Servicing Spares and Tools
6S = Automatic Stabilisers, Major Components, Servicing Spares and Tools
6T = Aircraft Automatic Pilots, Marks 9, 10, 10A, 13, SEP 2, 14 and 17, Major Components, Servicing Spares and Tools
6W = Instrumemnt Ancillaries to Radio Equipment
6Z = Radio activity Detection Equipment and Accessories, Unit and Major Servicing Spares

9 = Bomb and Torpedo Sights
9A = Aircraft Towed Target Gear
9B = Armament Ground Instructional Equipment

10A = Miscellaneous Radio (Wireless) Equipment
10AB = Miscellaneous Radio (Radar) Equipment
10AC = Unassembled Items peculiar to Radio with Generic Headings similar to those in Sections 28 and 29
10AD = Items and Assemblies performing Circuit Functions (Nomenclature commencing Letters A-K)
10AD = Items and Assemblies performing Circuit Functions (Nomenclature commencing Letters L-Z)
10AF = Calculating, Indicating and Measuring Equipment
10AG = Tools and Tool Boxes peculiar to Radio
10AH = Telephone Head Equipment, Microphones and Receivers
10AJ = Mountings and their Component Parts
10AK = Dials, Handles, Knobs,Plates, Escutcheon, Pointers, Pressbuttons and Scales
10AL = Screens and Insulating Components and their Assemblies
10AM = Labels (Radio)
10AP = Boxes, Cases, Covers and Trays, other Cases, Transit
10AQ = Furniture, Tentage, textile Materials and Ventilator Equipment, peculiar to Radio
10AR = Machinery, Machine and Mechanical Parts other than those in Section 10AC
(Nomenclature commencing Letters A-K)
10AR = Machinery, Machine and Mechanical Parts other than those in Section 10AC
(Nomenclature commencing Letters L-Z)
10AT = Windows and Visors
10AU = Strip Metallic
10B = Radio (Wireless and Radar) Aerial and Mast Equipment and Insulators
10BB =Radio (Radar) Aerial and Mast Equipment and Insulators
10C = radio Chokes, Capacitors and Inductors (see also Joint-Service Catalogue)
10CV = Joint Service Common Valves
10D = Radio (Wireless and Radar) Equipment, Modulators, Panels, Receivers, Transmitters etc.
10DB = Radio (Radar) Equipment, panels, Power Units, Racks, Receivers and Transmitters
10E = Magnets and Radio Valves (Industrial Types)
10F = Radio (Wireless and Radar) Starters and Switch Gear
10FB = Radio (radar) starters and Switch Gear
10G = Ground Telephone and Telegraph Equipment
10GP = Ground Telephone and Telegraph Equipment – Post Office Pattern
10H = Radio Connectors, Discs Indicating, Fuses, Leads, Plugs and Sockets and Ancillary Parts, Holders and Terminals.
10HA = Radio (Wireless and Radar) Connectors, Cords Instrument and Leads
10J = Radio Remote Controls
10K = Radio (Wireless and Radar) Power Units and Transformers
10KB = Radio (Radar) Power Units and Transformers
10L = Radio (Wireless and Radar) Control Units
10LB = Radio (Radar) Control Units
10P = Radio (Wireless and Radar) Filter and Receiver Units
10PB =Radio (Radar) Filter and Receiver Units
10Q = Radio (Wireless and Radar) Indicating Units
10QB = Radio (Radar) Indicating Units
10R = Radio (Wireless and Radar) Transmitter Units
10RB =Radio (Radar) Transmitter Units
10S = Radio (Wireless and Radar) Test Equipment
10SB = Radio (Radar) Test Equipment
10T = Radio Monitors and Wavemeters
10U = Radio (Wireless and Radar) Amplifying Units, Loudspeakers and Sound Reproduction Equipment
10UB = Radio (Radar) Amplifying Units and Loudspeakers
10V = Radio (Wireless and Radar) Oscillator Units
10VB = Radio (Radar) Oscillator Units
10W = Radio Resistors and miscellaneous Spares
10X = Radio Crystal Units
10Y = Cases Transit (general Radio purposes)

11A = Aircraft Bomb Gear
11C = Rocket Projector Gear

12A= Bombs (Live)
12B= Bombs (Dummy)
12C= Ammunition
12E = Torpedoes
12F= Misc. Armament

13 = Drawing Instruments

14A = Cameras
14B = Photographic Processing Equipment, Enlargers and Accessories
14C = Projection, Assessing Apparatus and Epidiascopes
14H = Photographic Test Apparatus

15A = Man-carrying Parachutes
15C = Equipment-dropping and Sea-rescue Apparatus
15D = Air Sea Rescue and Equipment, and Supply-dropping Parachutes

22C = Flying Clothing & Equipment

25A = Propellors
25B = Aircraft Radiators
25D = Spinners for Fixed Pitch Propellers and Fairey Spares for Metal Propellers

27A = Aircraft Wheel Equipment
27B = Aircraft Air and Oil Filters, Fuel and Oil Coolers
27C = Survival Equipment
27D = Miscrellaneous Aircraft Cover Equipment
27F = Aircraft Pumps and fuelling Equipment (Airborne)
27G = Aircraft Brake System Equipment
27H = Miscellaneous Aircraft Equipment
27J = Aircraft Control Handles with Gun, Camera, R.P. and Brake Operating Mechanisms
27K = Teleflex Aircraft Remote Control Equipment
27KA = Exactor Aircraft Remote Control Equipment
27KB = Aircraft Controls – Roller Chains
27KD = Pressurised Cabin Equipment – Normalair
27M = Aircraft Hydraulic and Undercarriage Equipment – Lockheed
27N = Airborne Fire Fighting Equipment
27R = B.L.G. Oleo Leg Equipment
27S = Standard Ball and Roller Bearings other than M.T.
27T = Controllable Gills
27U = Airborne Heaters
27UA = Aircraft Cabin Cooling Equipment
27V = Aircraft Controls – Teddington
27VA = Aircraft Controls – Dunlop
27VC = Aircraft Controls – Palmers
27W = Aircraft Hydraulic and Undercarriage Equipment, Standard Design
27WW = Aircraft Windscreen Wiper Equipment
27Z = Turner Duplex Hand Pumps for Aircraft Hydraulic Systems
27ZA = Exactor Self Sealing Couplings

28D = Bolts A.G.S.
28E = Clips A.G.S.
28F = Couplings A.G.S.
28FP = Aircraft Fastner and Quick Release Pins
28G = Eyebolts A.G.S.
28H = Ferrules A.G.S.
28J = Filler Caps and Fuel Filters A.G.S.
28K = Fork Joints A.G.S.
28L = Locknuts, Lockwashers A.G.S.
28M = Nuts A.G.S.
28N = A.G.S. Miscellaneous A to O
28P = Pins A.G.S.
28Q = Rivets A.G.S.
28R = A.G.S. Miscellaneous P to R
28S = Screws A.G.S. Miscellaneous A to O
28T = Studs A.G.S.
28U = Trunnions and Turnbuckles A.G.S.
28V = Unions A.G.S.
28W = Washers A.G.S.
28X = Wire A.G.S.
28Y = A.G.S. Miscellaneous S to Z

29A = Bolts and Nuts, General Hardware
29B = Screws, General Hardware
29C = Eyelets, Roves, Screw Cups, Washers, General Hardware
29E = Pins, Woodruff Keys, General Hardware
29F = Rivets, General Hardware

40H = Gun Turret Cases and Airtight Containers

50A = Aircraft Gun Turrets
50CC = Boulton Paul Gun Turret and Gun Mounting Tools
50DD = Bristol Gun Turret Tools
50EE = Frazer Nash Gun Turret Tools
50H = Aircraft Gun Turret Maintenance Equipment
50J = Free Gun Mountings

52 = Recognition Models

54A = Plotting Equipment

71B = Plants (Mobile, Transportable and Static) and Plant Accessories

Sadly the face of my example is marred by a crude glue repair round the edges of the Perspex, this glue has dried and cracked and has clearly been in place for many years.

The rear of the ammeter has two brass contacts that allow the instrument to be wired into an electrical system for use:imageWhilst this instrument was never actually used in a spitfire or indeed any other aircraft, it was a lucky find for £2 in a large box of vintage plugs and so was a great little addition to the collection and the sort of little find I love having.

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