« Previous Next »

PMD Film Traction and Lamp Modules

Technical Information

Catalogue No: C1105
Category: Navigation/Inertial
Object Type: Module/Sub-Assembly/Component
Object Name: PMD Film Traction and Lamp Modules
Part No: 3892/75511
Serial No: 131
Manufacturer: Ferranti
Division: Unknown
Platform(s): Tornado
Year of Manufacture: circa 1985
Dimensions: Width (mm): 162
Height (mm): 163
Depth (mm): 188
Weight (g): 4,800
Location: Rack RAA08 [Main Store]

[film access cover underside]
Film Traction Module
Serial No 131
Made by Ferranti Scotland
Mods 1, 2, 5, 6, 9, 11
[condensing lens assembly]
x6.8 CB107496
[written marks]
M 1.680
L 1.675
R 1.672


The rear of the unit shows the finned heatsink cover of the quartz-halogen lamp holder; its turnbuckle fasteners allowing quick cover opening for a speedy lamp change. The raised cover reveals the film transport mechanism; the door's sliding latch eases opening, again allowing another quick change, in this case, a film change to suit the aircraft's next mission.

Originally maps used with  moving map displays had a major disadvantage in that it was not possible to annotate them with planned route, target information and other tactical data; this had to be marked up on a hand-held map as an adjunct to the moving map. GEC Ferranti, developed the combined map and electronic display (COMED) system, in which the map is electronically annotated with intelligence or navigation data appropriate to the particular mission. Using no more space than a conventional moving map, COMED provides a colour topographical map display annotated with dynamic navigation information as required; this can include aircraft track and commanded track, present position, locations of known hostile detection or anti-aircraft devices, and tactical information such as the delineation of forward edge of the battle area. In addition, the system can print out alphanumeric information such as time to go to fix point or target.

COMED’s CRT and projection facilities permit it to perform other operational tasks. These can include the display of high-resolution high contrast symbology in raster form from radar, low light television or FLIR sensors. Electronic countermeasures threats can also be shown up. Tabular displays of weapons status, destination co-ordinates, or other tactical information can be shown on tabular ‘forms’ projected ’from images stored on the film. The system can be programmed with a library of aircraft and engine checklists. COMED can also act as a backup primary flight information display, particularly for the horizontal situation and attitude director indicators.

COMED interfaces with the main aircraft navigation computer via a MIL-STD-1553 serial digital data link. From a knowledge of film strip layout, aircraft present position and demanded scale, the main computer calculates the appropriate map drive words and transmits them to COMED by the data link. Within the display the information is converted into a form suitable for driving the map servo resolvers.

COMED uses standard 35 mm colour film up to 57 ft (17 m) long. Typically this provides coverage of an area of 10 000 nm2 at a scale of 1/250000, plus selected target areas at 1/50000 and sufficient film frames for tabulated displays. Film replacement can be achieved through a side access panel in under a minute.

More than 1000 systems have been supplied for the McDonnell Douglas F/A-18 Hornets with the US Navy and the armed forces of Australia, Canada and Spain. They are delivered to Bendix Flight Systems Division, the projected map assembly (PMA) forming part of the Bendix horizontal situation indicator, a combined map and electronic display for that aircraft. It projects a coloured topographical moving map image superimposed with data from a CRT image.  The system was ordered by the Indian Air Force for its Sepecat Jaguars made under licence by Hindustan Aero-nautics. The first production COMED system was delivered during early 1983. In May 1986 CEDAM (the latest variant of COMED) was selected for the Tornado ECR version ordered by the German Air Force. Deliveries of some 40 systems, plus spares, began in 1988.

Dimensions: (CRT face) 139.7 x 139.7 mm

The Tornado originally came in two variants; the Interdictor Strike Version (IDS) for the German, Air Force and Navy, Italian Air Force, and the Royal Air Force, and the Air Defence Variant (ADV) for the Royal Air Force only. Marconi-Elliott Avionic Systems provided a wide range of equipment for both variants.

• Digital Autopilot Flight Director System (AFDS)in conjunction with Aeritalia, Italy
• Command Stability Augmentation System (CSAS)  in conjunction with Bodenseewerk, Germany
• Quadruplex Actuator Integrated into Fairey Hydraulics power control unit
• Stores Management System (SMS) in conjunction with Selenia, Italy
• Fuel Flowmeter System in conjunction with Teldix, Germany and OMI, Italy
• TV Tabular Display System in conjunction with AEG Telefunken, Germany
• Combined Radar and Projected Map Display (CRPMD) from Ferranti
• E-Scope Display System
• Triplex Transducer Unit
• Central Suppression Unit
• Engine Control Unit

By 1980 the Enhanced E-Scope Display (EESD) was under development. This was was a digital design with a frame store, rather than the analogue design and long persistence phosphor CRT of the original E-Scope Display (ESD). The EESD part number was 79-061-xx and this version was probably fitted to the majority of Tornado IDS aircraft.

RAF IDS variants were initially designated the Tornado GR1 with two variants called the Tornado GR1A and Tornado GR1B; the Tornado F3 was yet another version.

The contract covering the development and production investment for the Royal Air Force's mid-life update (MLU) for their 229 Tornado GRl and F3 aircraft was signed in April 1989. The upgrade included the following:

• Introduction of a new avionics architecture built around a 1553 databus.
• New sensors & Displays consisting of a Forward Looking Infra-red sensor, a Pilot's Multi-Function Display with digital map, wide angle HUD, Computer Symbol Generator, Video recording System and a Computer loading System.
• New Armament Control System consisting of a Stores Management System, a Weapon Interface Unit linked to a 1553 databus within a 1760 interface.
• A Night Vision Goggle compatible cockpit and the aircraft is also equipped with Forward Looking InfraRed (FLIR)
• Terrain Reference Navigation /Terrain Following Display/Terrain Following Switching & Logic Unit /Covert RadAlt.

Ferranti won the contract for the new HUD, Active Matrix Liquid Crystal Displays (AMLCD) to replace the TV Tabs, EHDD and E-scope. To support the new avionics a new Computer Signal Generator (CSG), with several times the computing capacity of the original Tornado main computer, and using the new high level ADA progamming language was procured

The Ferranti Nite-Op jettisonable NVGs were also procured under a separate contract.

In the event the MLU project stalled. In March 1993 a new Mid-Life Upgrade (MLU) project was launched and in1994 the UK signed a contract for MLU of GR1/GR1A/GR1Bs to GR4/GR4A standard.

Click to enlarge Click to enlarge Click to enlarge Click to enlarge Click to enlarge