(c)
A torque-load condition in which a torque load of 1.33P (in foot-pounds)is applied to the ski about the vertical axis through the centerline of the pedestal bearings.
FAR29.511 :[Groundload : unsymmetricalloads on multiple-wheel units.]
(a)
[In dual-wheel gear units, 60 percent of the total groundreaction for the gear unit mustbe appliedto one wheel and40percenttothe other.
(b)
To provide for the case of one de.ated tire, 60 percent of the speci.ed load for the gear unit mustbe appliedto either wheel exceptthatthe verticalground reaction may not be less than the full static value.
(c)
Indetermining the totalload on agear unit, the transverse shiftin theload centroid, due to unsymmetrical load distribution on the wheels, may be neglected.]
Amdt. 29-3, E.. 2/25/68
73.5 Water Loads
FAR29.519 :Hull type rotorcraft :[Water-based and amphibian.]
(a) [General. For hull type rotorcraft, the structure must be designed to withstand the waterloading setforthinparagraphs(b),(c), and(d) of this section considering the most severe wave heights and pro.les for which approval is desired. The loads for thelanding conditions ofparagraphs(b) and(c) of this section mustbedeveloped anddistributed along and among thehull and auxiliary.oats,if used,inarational and conservative manner, assuming a rotor lift not exceeding two-thirds of the rotorcraft weight to act throughout the landing impact.
(b)
Vertical landing conditions. The rotorcraft must initially contact the most critical wavesurfaceat zeroforward speedinlikelypitch and roll attitudes which resultin critical design loadings. The vertical descent velocity may not be less than 6.5 feet per second relative to the mean water surface.
(c)
Forward speed landing conditions.The rotorcraft must contact the most critical wave atforward velocitiesfrom zero up to30knotsinlikelypitch, roll, andyaw attitudes and with a vertical descent velocity of not less than 6.5 feet per second relative to the meanwatersurface.A maximumforward velocity oflessthan30knotsmaybe used in design if it can be demonstrated that the forward velocity selected would not be exceeded in a normal one-engine-out landing.]
(d)
Auxiliary .oat immersion condition.In addition to theloadsfrom thelanding condi-tions, the auxiliary .oat, and its support and attaching structure in the hull, must be designed for the load developed by a fully immersed .oat unless it can be shown that full immersion of the .oat is unlikely, in which case the highest likely .oat buoyancy load must be applied that considers loading of the .oat immersed to create restoring moments compensating for upsetting moments caused by side wind, asymmetrical rotorcraft loading, water wave action, and rotorcraft inertia.
Amdt. 29-30, E.. 4/5/90
FAR 29.521 : Float landing conditions.
If certi.cationfor .oat operation[(including.oat amphibianoperation)]isrequested, therotorcraft, with.oats,mustbedesignedtowithstandthefollowingloading conditions (wherethelimitloadfactorisdeterminedunderSec.29.473(b) or assumed tobe equal to that determined for wheel landing gear) :
(a)
Up-load conditions in which–
(1)
A load is applied so that, with the rotorcraft in the static level attitude, the resultant water reactionpasses vertically through the center ofgravity; and
(2)
The verticalloadprescribedin subparagraph(1) ofthisparagraphis applied simultaneously with an aft component of 0.25 times the vertical component.
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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(28)
