(b)
The likely failure of any heat exchanger using fuel as one of its .uids may not result
in a hazardous condition.] Amdt. 25-40, E.. 5/2/77
′
Elodie Roux. Septembre 2003
Subpart E : Powerplant
FAR 25.953 : Fuel system independence.
Each fuel system must meet the requirements of Sec. 25.903(b) by–
(a)
Allowing the supply of fuel to each engine through a system independent of each part of the system supplying fuelto any other engine; or
(b)
Any other acceptable method.
FAR25.954 :[Fuel systemlightningprotection.]
[Thefuelsystem mustbedesigned and arranged topreventtheignition offuel vapor within the system by–
(a)
Direct lightning strikes to areas having a high probability of stroke attachment;
(b)
Swept lightning strokes to areas where swept strokes are highly probable; and
(c)
Corona and streamering at fuel vent outlets.] Amdt. 25-14, E.. 10/10/67
FAR 25.955 : Fuel .ow.
(a)
Each fuel system must provide at least 100 percent of the fuel .ow required under each intended operating condition and maneuver. Compliance must be shown as follows :
(1)
Fuel mustbedelivered to each engine at apressure withinthelimits speci.ed in the engine type certi.cate.
(2)
Thequantity offuel in the tank may not exceed the amount established as the unusablefuel supply forthattank underthe requirements ofSec.25.959plus that necessary to show compliance with this section.
(3)
Each main pump must be used that is necessary for each operating condition and attitude for which compliance with this section is shown, and the appro-priate emergency pump must be substituted for each main pump so used.
(4)
If there is a fuel .owmeter, it must be blocked and the fuel must .ow through the meter or its bypass.
(b)
[If an engine can be supplied with fuel from more than one tank, the fuel system must–
(1)
For each reciprocating engine, supply the full fuel pressure to that engine in not more than 20 seconds after switching to any other fuel tank containing usablefuel when engine malfunctioningbecomes apparentdue to thedepletion ofthefuel supply in any tankfrom which the engine canbefed; and
(2)
For each turbine engine, in addition to having appropriate manual switching capability, be designed to prevent interruption of fuel .ow to that engine, without attention by the .ight crew, when any tank supplying fuel to that engine is depleted of usablefuel during normal operation, and any other tank, that normally supplies fuel to that engine alone, contains usable fuel.]
Amdt. 25-11, E.. 6/4/67
FAR 25.957 : Flow between interconnected tanks.
If fuel can be pumped from one tank to another in .ight, the fuel tank vents and the fuel transfer system must be designed so that no structural damage to the tanks can occur because of over.lling.
FAR 25.959 : Unusable fuel supply.
The unusablefuelquantity for eachfuel tank anditsfuel system components mustb established at notlessthanthequantity at which the .rst evidenceof enginemalfunction occurs under the most adverse fuel feed condition for all intended operations and .ight maneuversinvolvingfuelfeedingfromthattank.[Fuel system componentfailure need not be considered.] Amdt. 25-40, E.. 5/2/77
FAR 25.961 : Fuel system hot weather operation.
(a)
The fuel system must perform satisfactorily in hot weather operation. This must be shown by showing that the fuel system from the tank outlets to each engine is pressurized,under allintended operations, so astoprevent vaporformation, or must be shownbyclimbingfrom the altitude ofthe airport electedbythe applicant to the maximum altitude established as an operating limitation under Sec. 25.1527. If a climbtestis elected, there maybe no evidence of vaporlock or other malfunctioning during the climb test conducted under the following conditions :
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本文鏈接地址：FAA規(guī)章 美國聯(lián)邦航空規(guī)章 Federal Aviation Regulations 3(114)
