25.333 and Sec. 25.337, the yawing maneuvers prescribed in Sec. 25.351, and the vertical andlateralgust conditionsprescribedinSec.25.341(a), at each setting and the maximum speed associated withthat setting; and]
(b)
If the device has automatic operating or load limiting features, the airplane must bedesignedfor the maneuver andgust conditionsprescribedinparagraph(a) of this section, at the speeds and corresponding device positions that the mechanism allows.
Amdt. 25-86, E.. 3/11/96
46.5 Control Surface and System Loads
FAR 25.391 : Control surface loads : general.
[The control surfaces must be designed for the limit loads resulting from the .ight conditions in Secs. 25.331, 25.341(a), 25.349 and 25.351 and the ground gust conditions in Sec. 25.415, considering the requirements for–]
(a)
Loads parallel to hinge line, in Sec. 25.393;
(b)
Pilot e.ort e.ects, in Sec. 25.397;
(c)
Trim tab e.ects, in Sec. 25.407;
(d)
Unsymmetrical loads, in Sec. 25.427; and
(e)
[Auxiliaryaerodynamic surfaces, in Sec. 25.445.] Amdt. 25-86, E.. 3/11/96
FAR 25.393 : Loads parallel to hinge line.
(a)
Control surfaces and supporting hinge brackets must be designed for inertia loads acting parallel to the hinge line.
(b)
In the absence of more rational data, the inertia loads may be assumed to be equal to KW, where–
(1)
K =24 for vertical surfaces;
(2)
K =12 for horizontal surfaces; and
(3)
W = weight of the movable surfaces.
FAR 25.395 : Control system.
(a)
Longitudinal, lateral, directional and drag control systems and their supporting structures must be designed for loads corresponding to 125 percent of the com-puted hinge moments of the movable control surface in the conditions prescribed in Sec. 25.391.
(b)
[The system limit loads, except the loads resulting from ground gusts, need not exceed theloadsthat canbeproducedby thepilot(orpilots) andby automatic or power devices operating the controls.
(c) The loads must not be less than those resulting from application of the minimum forcesprescribed in Sec. 25.397(c).]
Amdt. 25-72, E.. 8/20/90
FAR 25.397 : Control system loads.
(a)
General.The maximum and minimumpilotforces,speci.edinparagraph(c) of this section, are assumedto act at the appropriate controlgrips orpads(in a manner simulating .ight conditions) and to be reacted at the attachment of the control system to the control surface horn.
(b)
Pilot e.ort e.ects.Inthecontrol surface .ightloading condition,theairloadsonmo-vable surfaces and the corresponding de.ections need not exceed those that would result in .ight from the application of any pilot force within the ranges speci.ed inparagraph(c) ofthis section.Two-thirdsofthe maximum values speci.edfor the aileron and elevator may be used if control surface hinge moments are based on reliable data. In applying this criterion, the e.ects of servo mechanisms, tabs, and automatic pilot systems, must be considered.
(c)
Limit pilot forces and torques. The limit pilot forces and torques are as follows :
Control Maximum forces or torques Minimum forces or torques
Aileron : Stick Wheel1 100 lbs 80 D in.-lbs.2 40 lbs. 40 D in.-lbs.
Elevator : Stick Wheel (symmetrical) Wheel (unsymmetrical)3 250 lbs 300 lbs - 100 lbs. 100 lbs. 100 lbs.
Rudder 300 lbs 130 lbs.
1 The critical parts of the aileron control system must be designed for a single
tangential force with a limit value equal to 1.25 times the couple force determined
from these criteria.
2 D = wheeldiameter(inches).
3 Theunsymmetricalforces[mustbe] applied at oneof the normalhandgrippoints
on the periphery of the control wheel.
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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(53)
