(ii) An assumed rotor lift of not more than 1.5 times that used in the limit drop tests prescribed in Sec. 29.725.
(4) Compliance withparagraphs(b) through(e) ofthis section mustbe shown with–
(i)
Thegearinits most critically de.ectedpositionforthelanding condition being considered; and
(ii)
Theground reactions rationally distributed along thebottom of the skid tube.
(b)
Vertical reactions in the level landing attitude.In the level attitude, and with the ro-torcraft contactingtheground alongthebottom ofboth skids, the vertical reactions mustbe applied asprescribedinparagraph(a) of this section.
(c)
Drag reactions in the level landing attitude. In the level attitude, and with the rotorcraft contacting the ground along the bottom of both skids, the following apply :
(1)
The vertical reactions must be combined with horizontal drag reactions of 50 percent of the vertical reaction applied at the ground.
(2)
Theresultantgroundloadsmust equal theverticalload speci.edinparagraph (b)of this section.
(d)
Sideloads in the level landing attitude. In the level attitude, and with the rotorcraft contacting the ground along the bottom of both skids, the following apply :
(1)
The verticalground reaction mustbe–
(i)
Equalto the verticalloads obtainedin the condition speci.edinparagraph (b)ofthis section; and
(ii)
Divided equally among the skids.
(2)
The verticalground reactions mustbe combined with ahorizontal sideload of 25 percent of their value.
(3)
[The totalsideload mustbe applied equallybetween skids and along thelength of the skids.]
(4)
The unbalanced moments are assumed to be resisted by angular inertia.
(5)
The skid gear must be investigated for–
(i)
Inward acting sideloads; and
(ii)
Outward acting sideloads.
(e)
One-skid landing loads in the level attitude. In the level attitude, and with the ro-torcraft contacting the ground along the bottom of one skid only, the following apply :
(1)
The verticalloadon theground contact side mustbe the same as that obtained onthat sideinthe condition speci.edinparagraph(b) of this section.
(2)
The unbalanced moments are assumed to be resisted by angular inertia.
(f)
Special conditions.In additiontothe conditions speci.edinparagraphs(b) and(c) of this section,the rotorcraftmustbedesignedforthefollowingground reactions:
(1) Aground reactionload acting up and aftat anangleof45'to the longitudinal axis of the rotorcraft. This load must be–
(i) Equal to 1.33 times the maximum weight;
′
Elodie Roux. Septembre 2003
Subpart C : Strength Requirements
(ii) Distributed symmetrically among the skids;
(iii) Concentrated at theforward end of the straightpart of the skid tube; and
(iv) Applied only to the forward end of the skid tube and its attachment to the rotorcraft.
(2) With the rotorcraft in the level landing attitude, a vertical ground reaction load equal to one-half of the verticalloaddetermined underparagraph(b) of this section. This load must be–
(i)
Applied only to the skid tube and its attachment to the rotorcraft; and
(ii)
[Distributed equally over 33.3 percent of the length between the skid tube attachments and centrally located midway between the skid tube attachments.]
Amdt. 29-30, E.. 4/5/90
FAR 29.505 : Ski landing conditions.
If certi.cation for ski operation is requested, the rotorcraft, with skis, must be de-signed to withstand the following loading conditions (where P is the maximum static weight on each ski with the rotorcraft at design maximum weight, and nzcl is the limit load factor determined under Sec. 29.473(b)) :
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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(27)
