K :K =0.8, except thatlower values maybe usedifitis shown that the .oats are incapable of submerging at a speed of 0.8VS0 in normal operations;
VS0 :seaplanestalling speed(knots) withlanding .apsextended in the appropriateposition and with no slipstream e.ect; and
g :acceleration due to gravity(ft/sec2).
(g) Float bottom pressures. The .oat bottom pressures must be established under Sec. 23.533, except that the value of K2 in the formulae may be taken as 1.0. The angle of dead rise to be used in determining the .oat bottom pressures is set forth in paragraph(b) of this section.]
Amdt. 23-45, E.. 09/07/93
FAR23.537 :[Seawingloads.]
[Seawingdesign loads must be based on applicable test data.] Amdt. 23-45, E.. 09/07/93
30.9 Emergency Landing Conditions
FAR 23.561 : General.
(a)
The airplane, although it may be damaged in emergency landing conditions, must be designed as prescribed in this section to protect each occupant under those conditions.
(b)
The structure mustbedesigned to[give each occupant every reasonable chance of escaping serious injury when–]
(1)
Proper use is made of seats, safety belts, and shoulder harnesses provided for in the design;
(2)
The occupant experiences the static inertia loads corresponding to the follo-wing ultimate load factors–
(i)
Upward,3.0gfor normal, utility, andcommuter category airplanes, or4.5g for acrobatic category airplanes;
(ii)
Forward, 9.0g;
(iii) Sideward, 1.5g; and
(iv) Downward, 6.0g when certi.cation to the emergency exit provisions of Sec. 23.807(d)(4) is requested; and
(3)
The items of mass within the cabin, that could injure an occupant, experience the static inertia loads corresponding to the following ultimate load factors–
(i)
Upward, 3.0g;
(ii)
Forward, 18.0g; and
(iii) Sideward, 4.5g.
(c)
Each airplane with retractable landing gear must be designed to protect each occu-pant in a landing–
(1)
With the wheels retracted;
(2)
With moderate descent velocity; and
(3)
Assuming, in the absence of a more rational analysis–
(i)
A downward ultimate inertia force of 3g; and
(ii)
A coe.cient of friction of 0.5 at the ground.
(d)
If it is not established that a turnover is unlikely during an emergency landing, the structure must be designed to protect the occupants in a complete turnover as follows :
(1)
The likelihood of a turnover may be shown by an analysis assuming the follo-wing conditions–
(i)
[The most adverse combination ofweight and center ofgravityposition;
(ii)
[Longitudinal load factor of 9.0g;
(iii) [Vertical load factor of 1.0g;and
(iv) [For airplanes withtricyclelandinggear, the nose wheel strutfailed with the nose contacting the ground.]
(2)
For determining the loads to be applied to the inverted airplane after a turno-ver, an upward ultimate inertia load factor of 3.0g and a coe.cient of friction with the ground of 0.5 must be used.
′
Elodie Roux. Septembre 2003
Subpart C : Structure
(e) [Except as provided in Sec. 23.787(c), the supporting structure must be designed torestrain,underloadsuptothosespeci.edinparagraph(b)(3) ofthissection, each item of mass that could injure an occupant if it came loose in a minor crash landing.]
Amdt. 23-48, E.. 03/11/96
FAR 23.562 : Emergency landing dynamic conditions.
(a)
Eachseat/restraint systemfor usein a normal, utility, or acrobatic category airplane must be designed to protect each occupant during an emergency landing when–
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本文链接地址：FAA规章 美国联邦航空规章 Federal Aviation Regulations 2(16)
