(b)
The amount of trapped oil must be enough to accomplish the feathering operation and must be available only to the feathering pump.
(c)
The ability of the system to accomplish feathering with the trapped oil must be shown. This may be done on the ground using an auxiliary source of oil for lubri-cating the engine during operation.
(d)
[Provision must be made to prevent sludge or other foreign matter from a.ecting the safe operation of the propeller feathering system.]
Amdt. 25-38, E.. 2/1/77
48.5 Cooling
FAR 25.1041 : General.
[Thepowerplantand auxiliarypower unit coolingprovisions mustbe able to maintain the temperatures of powerplant components, engine .uids, and auxiliary power unit components and .uids within the temperature limits established for these components and .uids,underground,water,and.ightoperating conditions,and afternormal engine or auxiliarypower unit shutdown, orboth.] Amdt. 25-38, E.. 2/1/77
FAR 25.1043 : Cooling tests.
(a)
General.Compliance withSec.25.1041mustbe shownbytests, under criticalground, water, and .ight operating conditions. For these tests, the following apply :
(1)
If the tests are conducted under conditions deviating from the maximum am-bient atmospheric temperature, the recorded powerplant temperatures must be corrected underparagraphs(c) and(d) of this section.
(2)
No correctedtemperaturesdetermined under subparagraph(1) ofthispara-graph may exceed established limits.
(3)
For reciprocating engines, the fuel used during the cooling tests must be the minimum grade approved for the engines, and the mixture settings must be thosenormally usedinthe .ight stagesforwhich thecooling testsareconduc-ted. The test procedures must be as prescribed in Sec. 25.1045.
(b)
[Maximum ambient atmospheric temperature. A maximum ambient atmospheric temperature corresponding to sea level conditions of at least 100 degrees F must be established. The assumed temperature lapse rate is 3.6 degrees F per thousand feet of altitude above sea level until a temperature of -69.7 degrees F is reached, above which altitude the temperature is considered constant at -69.7 degrees F. However, for winterization installations, the applicant may select a maximum am-bient atmospheric temperature corresponding to sea level conditions of less than 100 degrees F.]
(c)
Correctionfactor(except cylinderbarrels).Unless a more rational correction applies, temperaturesof engine .uidsandpowerplant components(exceptcylinderbarrels) for which temperature limits are established, must be corrected by adding to them the di.erence between the maximum ambient atmospheric temperature and the temperature of the ambient air at the time of the .rst occurrence of the maximum component or .uid temperature recorded during the cooling test.
(d)
Correction factor for cylinder barrel temperatures. Unless a more rational correction applies, cylinderbarreltemperatures mustbe correctedby addingto them0.7times the di.erence between the maximum ambient atmospheric temperature and the temperature of the ambient air at the time of the .rst occurrence of the maximum cylinder barrel temperature recorded during the cooling test.
Amdt. 25-42, E.. 3/1/78
FAR 25.1045 : Cooling test procedures.
(a) Compliance with Sec. 25.1041 must be shown for the takeo., climb, en route, and landingstagesof.ightthat correspondtotheapplicableperformancerequirements.
′
Elodie Roux. Septembre 2003
Subpart E : Powerplant
The cooling tests must be conducted with the airplane in the con.guration, and operating under the conditions, that are critical relative to cooling during each stage of .ight. For the cooling tests, a temperature is ”stabilized” when its rate of change is less than 2'F. per minute.
(b)
Temperatures must be stabilized under the conditions from which entry is made into each stage of .ight being investigated, unless the entry condition normally is notoneduring which componentand engine .uid temperatureswould stabilize(in which case, operation through the full entry condition must be conducted before entry into the stage of .ight being investigated in order to allow temperatures to reach their natural levels at the time of entry). The takeo. cooling test must be preceded by a period during which the powerplant component and engine .uid temperatures are stabilized with the engines at ground idle.
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本文链接地址：FAA规章 美国联邦航空规章 Federal Aviation Regulations 4(3)
