CS-E 570 Oil System

• ED Decision 2007/015/R found in: EAR for CS-E Amendment 5

(ii) Provision must be made to prevent sludge or foreign matter from entering the Propeller feathering system. (iii) The design of the Engine oil system must be such that it is possible to complete the feathering and unfeathering operation under all normal operating conditions. (g) (1) Each brand and type of oil to be approved, and the associated limitations, must be declared and substantiated. (2) Any parameter of the oil specification which is likely to be critical for Engine functioning or durability must be identified so that, where necessary, Engine or rig testing using appropriate oil may be conducted. [Amdt. No.: E/1] CS-E 570 Oil System ED Decision 20 07 / 015 /R (See AMC E 570 ) (a) (1) The design of the oil system must be such as to ensure its proper functioning under all intended flight attitudes, installation, atmospheric and operating conditions, including oil temperature and expansion factors. (2) There must be design precautions - (i) To minimise the possibility of incorrect fitment of the closing device of the oil filling point or any other access point, or to preclude fluid loss in the event of incorrect fitment, and (ii) To prevent entrance into the oil tank or into any oil tank outlet of any object that might obstruct the flow of oil through the system, (3) Tank filler caps must be designed to provide an oil tight seal and designed so that they will not loosen in flight and must be marked with the word ‘oil’. (4) Provision must be made near each oil pressure connection provided for instrumentation so as to limit the loss of fluid in the event of a pipe Failure. (b) (1) All parts of the oil system that are not inherently capable of accepting contaminants likely to be present in the oil or otherwise introduced into the oil system must be protected by suitable filter(s) or strainer(s). These must provide a degree of filtration sufficient to preclude damage to the Engine and Engine equipment and have adequate capacity to accommodate contaminants in relation to the specified servicing intervals. (2) If the most critical main oil filter does not incorporate a by-pass, then it must have provision for appropriate indication to the flight crew of impending blockage. (c) Each filter or strainer that has a by-pass must be constructed and installed so that, if the filter or strainer element is completely blocked, the oil will flow through the rest of the system at a rate which is within the normal operating r ange of the system. In addition : (1) The design of any by-pass must be such that, when the by-pass is in operation, previously collected contaminants in the filter or strainer will not enter the Engine oil system downstream of the filter or strainer. (2) Indication of by-pass operation must be provided to permit appropriate maintenance action to be initiated. This indication need not be provided if the maintenance instructions require the same action to be taken following an impending blockage indication of the most critical main oil filter. (d) The oil system, including the oil tank expansion space, must be adequately vented. All atmospheric vents in the oil system must be located, or protected, to minimise ingress of foreign matter that could affect satisfactory Engine functioning. Venting must be so arranged that condensed water vapour which might freeze and obstruct the line cannot accumulate at any point. (e) (1) Except where the tank, its supports and all oil system components external to the Engine casing are Fireproof, a means must be provided to shut off the oil supply to the Engine. The means must be such that in the event of Failure of any oil system pipe, it will, when operated, prevent the discharge of hazardous quantities of oil. (2) When applicable, operation of the shut-off means must not prevent the utilisation of any oil supply intended for the Propeller feathering operation. (f) (1) Each un-pressurised oil tank must not leak when subjected to the maximum operating temperature and a differential pressure of 35 kPa. (2) Each oil tank must have, or have provision for, an oil quantity indicator. (3) If a Propeller feathering system depends on Engine oil, (i) There must be means to trap an amount of oil in the tank if the supply becomes depleted due to Failure of any part of the lubricating system other than the tank itself. The amount of trapped oil must be enough to accomplish one feathering operation taking into account deterioration in service, and must be available only to the feathering pump.