(c) [At all weights between the empty weight and the maximum weight declared for tie-down stated in the appropriate manual, any declared tie-down points and sur-rounding structure, control system, surfaces and associated gust locks, must be designed to withstand the limit load conditions that exist when the airplane is tied down and that result from wind speeds up to 65 knots horizontally from any direction.]
Amdt. 23-48, E.. 03/11/96
30.4 Horizontal Stabilizing and Balancing Surfaces
FAR 23.421 : Balancing loads.
(a)
Ahorizontal[surface] balancing loadis aload necessary to maintain equilibriumin any speci.ed .ight condition with no pitching acceleration.
(b)
Horizontal[balancing] surfaces mustbedesignedfor thebalancingloads occurring atanypointonthelimitmaneuvering envelopeandinthe .ap conditionsspeci.ed in Sec. 23.345.
Amdt. 23-42, E.. 02/04/91
FAR 23.423 : Maneuvering loads.
[Each horizontalsurface and its supporting structure, and the main wing of a canard ortandem wing con.guration,if that surfacehaspitch control,mustbedesignedforthe maneuvering loads imposed by the following conditions :
(a)
A sudden movement of the pitching control, at the speed VA, to the maximum aft movement, and the maximum forward movement, as limited by the control stops, orpilot e.ort, whicheveris critical.
(b)
A sudden aft movement of the pitching control at speeds above VA, followed by a forward movement of the pitching control resulting in the following combinations of normal and angular acceleration :
Condition Normal acceleration (n) Angular acceleration (radian/sec.2)
Nose-up pitching 1.0 +39 V nm(nm . 1.5)
Nose-down pitching nm . 39 V nm(nm . 1.5)
where– (1)nm =positivelimitmaneuveringloadfactor usedin thedesign of the airplane; and (2)V = initial speed in knots.
The conditions in this paragraph involve loads corresponding to the loads that may occur in a ”checked maneuver” (a maneuver in which the pitching control is suddenly displaced in one direction and then suddenly moved in the opposite direction). The de.ections and timing of the ”checked maneuver” must avoid ex-ceeding the limit maneuvering load factor. The total horizontal surface load for both nose-up and nose-downpitching conditionsisthe sum of thebalancing loads at V and the speci.ed value of the normalloadfactor n,plus the maneuveringload increment due to the speci.ed value of the angular acceleration.]
Amdt. 23-42, E.. 02/04/91
FAR 23.425 : Gust loads.
(a)
[Eachhorizontalsurface, otherthan a main wing, mustbedesignedforloads resulting from–]
(1)
Gust velocities speci.ed in Sec. 23.333(c) with .aps retracted; and
(2)
Positive and negativegusts of 25f.p.s. nominalintensity at VF , corresponding to the .ight conditions speci.ed in Sec. 23.345(a)(2).
(b)
[[Reserved.]
(c)
When determining the total load on the horizontal surfaces for the conditions speci-.ed inparagraph(a) of this section, the initialbalancing loadsfor steady unaccele-rated.ight atthepertinentdesignspeeds VF, VC, and VD must .rstbedetermined. Theincrementalloadresultingfromthegusts mustbe addedtotheinitialbalancing load to obtain the total load.
(d)
In the absence of a more rational analysis, the incremental load due to the gust must be computed as follows only on airplane con.gurations with aft-mounted, horizontal surfaces, unless its use elsewhere is shown to be conservative :]
Kg Ude Vaht Sht de
ΔLht = 498 1. da
where–
ΔLht :Incremental horizontal tail load (lbs.);
Kg :Gust alleviation factor de.ned in Sec. 23.341;
Ude :Derivedgustvelocity (f.p.s.);
V :Airplane equivalent speed (knots);
aht :[Slope of aft horizontal tail lift curve] (per radian);
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本文鏈接地址：FAA規(guī)章 美國(guó)聯(lián)邦航空規(guī)章 Federal Aviation Regulations 2(6)
