(1)
The loads on the main wheel tire, corresponding to the most critical combination of airplane weight(up to the maximum weight) and center ofgravityposition, and
(2)
Theloads corresponding totheground reactionsinparagraph(b) of this section, on the nose wheel tire, except asprovidedinparagraphs(b)(2) and(b)(3) of this section.
(b)
The applicable ground reactions for nose wheel tires are as follows :
(1)
The staticground reactionforthetire corresponding tothe most critical combination of airplane weight(up to maximum ramp weight) and center of gravity position with a force of 1.0g acting downward at the center of gravity. This load may not exceed the load rating of the tire.
(2)
The ground reaction of the tire corresponding to the most critical com-bination of airplane weight(up to maximumlanding weight) and center ofgravityposition combined withforces of1.0g downward and0.31g for-ward acting at the center of gravity. The reactions in this case must be distributed to the nose and main wheels by the principles of statics with a drag reaction equal to 0.31 times the vertical load at each wheel with brakes capable ofproducing thisground reaction.This nose tireload may not exceed 1.5 times the load rating of the tire.
(3)
The ground reaction of the tire corresponding to the most critical com-bination of airplane weight(up to maximum ramp weight) and center of gravity position combined with forces of 1.0g downward and 0.20g for-ward acting at the center of gravity. The reactions in this case must be distributed to the nose and main wheels by the principles of statics with a drag reaction equal to 0.20 times the vertical load at each wheel with brakes capable ofproducing thisground reaction.This nose tireload may not exceed 1.5 times the load rating of the tire.
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Elodie Roux. Septembre 2003
Subpart D : Design and Construction
(c)
Whenalandinggearaxleis .tted with morethanonewheel and tireassembly, such as dual or dual-tandem, each wheel must be .tted with a suitable tire of proper .t with a speed rating approved by the Administrator that is not exceeded under critical conditions, and with a load rating approved by the Administrator that is not exceeded by–
(1)
The loads on each main wheel tire, corresponding to the most critical combination of airplane weight(up to the maximum weight) and center ofgravityposition, when multipliedby afactor of1.07; and
(2)
Loads speci.ed in paragraphs (a)(2), (b)(1), (b)(2), and (b)(3) of this section on each nose wheel tire.
(d)
Each tireinstalled in a retractablelandinggear system must, at the maximum size of the tire type expectedin service,have a clearance to surrounding struc-ture and systemsthatis adequatetoprevent unintended contactbetweenthe tire and any part of the structure or systems.
(e)
[For an airplane with a maximum certi.cated takeo. weight of more than 75,000 pounds, tires mounted on braked wheels must be in.ated with dry nitrogen or other gases shown to be inert so that the gas mixture in the tire does not contain oxygen in excess of 5 percent by volume, unless it can be shownthatthetireliner material will notproduce a volatilegaswhenheated orthat means areprovided topreventtiretemperaturesfrom reaching unsafe levels.]
Amdt. 25-78, E.. 3/29/93
FAR 25.735 : Brakes.
(a)
[Approval. Each assembly consisting of a wheel(s) and brake(s) must be ap-proved.
(b)
Brake system capability.Thebrake system, associated systems and components must be designed and constructed so that :
(1)
If any electrical,pneumatic,hydraulic, or mechanical connecting or trans-mitting element fails, or if any single source of hydraulic or other brake operating energy supply islost,itispossibletobring the airplaneto rest with a braked roll stopping distance of not more than two times that obtainedin determining the landingdistance asprescribedin Sec.25.125.
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本文链接地址：FAA规章 美国联邦航空规章 Federal Aviation Regulations 3(81)
