LANCASTER HYDRAULIC SYSTEM [Main Title]
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- Title: LANCASTER HYDRAULIC SYSTEM [Main Title]
- Film Number: AMY 41
- Other titles:
- Summary: A very detailed training film for the hydraulic system of the Lancaster aircraft, illustrating each operational component, and their function within the overall system. The use of many animated diagrams, close up photography and accompanying narrative are particularly effective.
- Description: Reel one: The Lancaster hydraulic system is not complex but there is a lot of it. Hydraulic pressure powers five important services: the bomb doors, carburettor hot air intakes, fuel jettisoning, retractable under-carriage and landing flaps. The hydraulic pressure is generated by two pumps, one mounted on each of the two in-board aircraft engines. One pump alone can operate all the services should an engine fail during flight. A large animated diagram incorporating all the components is used with the narrative to explain the location of each component and its function within the system. The pumps draw hydraulic oil from the reservoir, deliver it to the filter and pass it to the automatic cut out valve. This valve effectively acts as a hydraulic clutch, cutting off the pressure to that service when its function has been completed. The paths of the service feed lines to the operational controls in the cockpit are shown, where the hydraulic accumulator is situated acting as a store of hydraulic power in an emergency. The operation of the five important services, controlled from the cockpit is shown in a series of film clips and diagrams. The bomb doors open and close; hot air is directed into the four engine carburettors; fuel is jettisoned from two hoses dropped down from the bomb bay to allow fuel to enter the atmosphere; the under-carriage is raised and lowered and the flaps are operated. Various safety devices are built into each system, most critically for the under-carriage. A hand operated pump mounted next to the reservoir provides sufficient hydraulic pressure for the hot air intakes and fuel jettison services should the engine driven pumps fail. Emergency lowering of the under-carriage and landing flaps is provided from a reservoir of compressed air with its own control system. Reel two: The film returns to the large animated diagram of the entire system showing the five services provided, the associated hydraulic plumbing and the pilot’s controls. Additional explanations for each service follow with an emphasis on the hydraulic reservoir (accumulator) and the automatic cut out valve, a very important component. This allows the pilot to initiate a service that is automatically shut down on completion, without further attention from the pilot. The five services receive oil from a common hydraulic rail of continuously circulating oil under the control of the cut out valves. These are pressure sensitive devices controlling the supply of oil to either a service or the hydraulic accumulator. The Hydraulic accumulator contains oil under air pressure, and a moving piston separating the two medium thus maintaining a constant oil pressure which will vary according to the rate of oil supply to the five services. This rate of supply is governed by the diameter of the supply pipe to a particular service. The hydraulic system must be tested periodically with the Lancaster on the ground, engines off and the aircraft jacked up to relieve the load on the under-carriage. An external hydraulic power supply is connected into the aircraft hydraulic system thus enabling all necessary tests, including the under-carriage and bomb doors to be completed.
- Alternative Title:
- Colour: B&W
- Digitised:
- Object_Number: AMY 41
- Sound: Sound
- Access Conditions:
- Featured Period: 1939-1945
- Production Date: 1943
- Production Country: GB
- Production Details: ROYAL AIR FORCE (Production sponsor) Brent Productions (Production individual)
- Personalities, Units and Organisations:
- Keywords:
- Physical Characteristics: Colour format: B&W Sound format: Sound
- Technical Details: Format: 35mm Number of items/reels/tapes: 2 Length: 1574ft
- HD Media:
- Link to IWM Collections page:
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