(b)
VNEi means instrument .ight never exceed speed, utilized instead of VNE for com-pliance with maximum limit speed requirements for instrument .ight.
(c)
Vmini meansinstrument .ight minimumspeed,utilizedincomplying with minimum limit speed requirements for instrument .ight.]
Amdt. 27-19, E.. 3/2/83
FAR27.B3 :[III.Trim.]
[It must be possible to trim the cyclic, collective, and directional control forces to zero at all approvedIFR airspeeds,power settings, and con.gurations appropriate to the type.] Amdt. 27-19, E.. 3/2/83
FAR27.B4 :[IV.Staticlongitudinalstability.]
(a)
[General. The helicopter must possess positive static longitudinal control force sta-bility at critical combinations of weight and center of gravity at the conditions speci.ed in paragraph IV(b) or (c) of this Appendix, as appropriate. The stick force must vary with speed so that any substantial speed change results in a stick force clearly perceptible to the pilot. For single-pilot approval, the airspeed must return to within 10 percent of the trim speed when the control force is slowly released for each trim condition speci.ed in paragraph IV(b) of this Appendix.
(b)
For single-pilot approval :
(1)
Climb. Stability must be shown in climb throughout the speed range 20 knots either side of trim with–
(i)
The helicopter trimmed at VYi ;
(ii)
Landinggear retracted(if retractable); and
(iii) Powerrequiredforlimit climb rate(atleast1,000fpm) at VYi or maxi-mum continuous power, whichever is less.
(2)
Cruise. Stability must be shown throughout the speed range from 0.7 to 1.1 VH or VNEi, whichever is lower, not to exceed ±20 knots from trim with–
(i)
The helicopter trimmed and power adjusted for level .ight at 0.9VH or 0.9VNEi, whichever is lower and
(ii)
Landinggear retracted(if retractable).
(3)
Slow cruise.Stability mustbe shownthroughoutthe speed rangefrom0.9Vmini to 1.3Vmini or 20 knots above trim speed, whichever is greater, with–
(i)
The helicopter trimmed and power adjusted for level .ight at 1.1Vmini ; and
(ii)
Landinggear retracted(if retractable).
(4)
Descent. Stability must be shown throughout the speed range 20 knots either side of trim with–
(i)
The helicopter trimmed at 0.8VH or 0.8VNEi (or 0.8Vle for the landing gear extended case), whichever is lower;
(ii)
Power requiredfor1,000fpmdescent attrim speed; and
(iii) Landing gear extended and retracted, if applicable.
(5)
Approach.Stability mustbeshownthroughoutthe speed rangefrom0.7 times the minimum recommended approach speed to 20 knots above the maximum recommended approach speed with–
(i)
Thehelicoptertrimmed atthe recommended approach speed or speeds;
(ii)
Landinggear extended and retracted,if applicable; and
(iii) Power required to maintain a 3'glidepath andpower required to main-tainthe steepest approachgradientfor which approvalis requested.
(c) Helicopters approved for a minimum crew of two pilots must comply with the pro-visions of paragraphs IV(b)(2) and IV(b)(5) of this Appendix.]
Amdt. 27-19, E.. 3/2/83
FAR27.B5 :[V.Staticlateral-directional stability.]
(a)
[Static directionalstability mustbepositive throughout the approved ranges of airs-peed,power,and vertical speed.In straight,steady sideslipsup to ±10'from trim, directional controlposition mustincreasein approximately constantproportionto angle of sideslip. At greater angles up to the maximum sideslip angle appropriate tothetype,increaseddirectional controlposition mustproduceincreased angle of sideslip.
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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(4)
