(3)
Immersion of auxiliary.oatsor sponsons,wing tips,propellerblades, orother parts not designed to withstand the resulting water loads.
(b)
Compliance withthe requirements ofparagraph(a) of this section mustbe shown–
(1)
In water conditions, from smooth to the most adverse condition established in accordance with Sec. 25.231;
(2)
In wind and cross-wind velocities, water currents, and associated waves and swells that may reasonably be expected in operation on water;
(3)
At speeds that may reasonably be expected in operation on water;
(4)
With sudden failure of the critical engine at any time while on water; and
(5)
At each weight and center ofgravityposition, relevant to each operating condi-tion, within the range ofloading conditionsfor which certi.cationis requested.
(c)
Inthe waterconditionsofparagraph(b) ofthis section,andinthe corresponding wind conditions, the seaplane or amphibian must be able to drift for .ve minutes with engines inoperative, aided, if necessary, by a sea anchor.
45.8 Miscellaneous Flight Requirements
FAR 25.251 : Vibration and bu.eting.
(a)
[The airplane must be demonstrated in .ight to be free from any vibration and bu.eting that wouldprevent continued safe .ightinanylikely operating condition.
(b)
Each part of the airplane must be demonstrated in .ight to be free from excessive vibration under any appropriate speed andpower conditions up to VDF/MDF.The maximum speeds shown must be used in establishing the operating limitations of the airplane in accordance with Sec. 25.1505.]
(c)
Except as provided in paragraph (d) of this section, there may be no bu.eting condition, in normal .ight, including con.guration changes during cruise, severe enough to interfere with the control of the airplane, to cause excessive fatigue to thecrew,ortocausestructuraldamage.Stall warningbu.eting withintheselimits is allowable.
(d)
There may be no perceptible bu.eting condition in the cruise con.guration in straight .ight at any speed up to VMO/MMO, except that stall warning bu.eting is allowable.
(e)
For an airplane with MD greater than 0.6 or with a maximum operating altitude greater than 25,000 feet, the positive maneuvering load factors at which the onset of perceptible bu.eting occurs must be determined with the airplane in the cruise con.guration for the ranges of airspeed or Mach number, weight, and altitude for whichthe airplaneis tobe certi.cated.The envelopes ofloadfactor, speed, altitude, and weight must provide a su.cient range of speeds and load factors for normal operations. Probable inadvertent excursions beyond the boundaries of the bu.et onset envelopes may not result in unsafe conditions.
Amdt. 25-77, E.. 7/29/92
′
Elodie Roux. Septembre 2003
Subpart B : Flight
FAR 25.253 : High-speed characteristics.
(a)
Speed increase and recovery characteristics. The following speed increase and reco-very characteristics must be met :
(1)
Operating conditions and characteristics likely to cause inadvertent speed in-creases(including upsetsinpitch and roll) mustbe simulated withthe airplane trimmed at any likely cruise speed up to VMO/MMO. These conditions and characteristics include gust upsets, inadvertent control movements, low stick force gradient in relation to control friction, passenger movement, leveling o. from climb, and descent from Mach to airspeed limit altitudes.
(2)
Allowing forpilot reactiontime after e.ectiveinherent or arti.cial speed war-ning occurs, it must be shown that the airplane can be recovered to a normal altitude and its speed reduced to VMO/MMO, without –
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：FAA规章 美国联邦航空规章 Federal Aviation Regulations 3(41)
