(2)
Theprobabilityoflanding withinitial contact on the rear wheel mustbe shown to be extremely remote.
(e)
Level landing attitude with only one forward wheel contacting the ground. In this attitude, the rotorcraft mustbedesignedforgroundloads as speci.edinparagraph (b)(1)and(3) of this section.
(f)
Side loads in the level landing attitude.In the attitudes speci.edinparagraphs(b) and(c) ofthis section,thefollowing apply :
(1) The side loads must be combined at each wheel with one-half of the maximum verticalgroundreactionsobtainedforthatwheel underparagraphs(b) and (c)of this section. In this condition, the side loads must be–
(i) For theforwardwheels,0.8 times the vertical reaction(on one side) acting inward, and 0.6 times the vertical reaction (on the other side) acting outward; and
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Elodie Roux. Septembre 2003
Subpart C : Strength Requirements
(ii) For the rear wheel, 0.8 times the vertical reaction.
(2) Theloads speci.edin subparagraph(1) of thisparagraph mustbe applied–
(i)
Attheground contactpointwiththe wheelinthetrailingposition(for non-full swiveling landing gear or for full swiveling landing gear with a lock, steering device, or shimmy damper to keep the wheel in the trailing position); or
(ii)
At the center of the axle(forfull swivelinglandinggear without alock, steering device, or shimmy damper).
(g)
Braked roll conditions in the level landing attitude. In the attitudes speci.ed in paragraphs(b) and(c) of this section, and with the shock absorbersintheir static positions, the rotorcraft must be designed for braked roll loads as follows :
(1)
Thelimit verticalload mustbebased onalimit verticalloadfactorof notless than–
(i)
1.0,forthe attitude speci.edinparagraph(b) of this section; and
(ii)
1.33,forthe attitude speci.edinparagraph(c) of this section.
(2)
For eachwheel withbrakes, adragload mustbe applied, at theground contact point, of not less than the lesser of–
(i)
0.8 times the vertical load; and
(ii)
The maximum based on limiting brake torque.
(h)
Rear wheel turning loads in the static ground attitude.Inthe staticground attitude, and with the shock absorbers and tiresin their staticpositions, the rotorcraft must be designed for rear wheel turning loads as follows :
(1)
A vertical ground reaction equal to the static load on the rear wheel must be combined with an equal side load.
(2)
Theload speci.edin subparagraph(1) of thisparagraph mustbe applied to the rear landing gear–
(i)
Through the axle,if thereis a swivel(the rearwheelbeing assumed tobe swiveled 90 degrees to the longitudinal axis of the rotorcraft); or
(ii)
At the ground contact point if there is a lock, steering device or shimmy damper(the rear wheelbeing assumed tobeinthetrailingposition).
(i)
Taxiing condition. The rotorcraft andits landinggear must be designedfor the loads that would occur whenthe rotorcraftistaxied overthe roughestground that may reasonably be expected in normal operation.
FAR 29.501 : Ground loading conditions : landing gear with skids.
(a)
General. Rotorcraft with landing gear with skids must be designed for the loading conditions speci.ed in this section. In showing compliance with this section, the following apply :
(1)
Thedesign maximum weight,center ofgravity,andloadfactormustbedeter-mined under Secs. 29.471 through 29.475.
(2)
Structural yielding of elastic spring members under limit loads is acceptable.
(3)
Design ultimate loads for elastic spring members need not exceed those obtai-ned in a drop test of the gear with–
(i)
A drop height of 1.5 times that speci.ed in Sec. 29.725; and
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本文链接地址：FAA规章 美国联邦航空规章 Federal Aviation Regulations 5(26)
