519 

Federal Aviation Administration, DOT 

§ 27.753 

(d) 

Operation tests. The proper func-

tioning of the retracting mechanism 
must be shown by operation tests. 

(e) 

Position indicator. There must be a 

means to indicate to the pilot when the 
gear is secured in the extreme posi-
tions. 

(f) 

Control.  The location and oper-

ation of the retraction control must 
meet the requirements of §§ 27.777 and 
27.779. 

(g) 

Landing gear warning. An aural or 

equally effective landing gear warning 
device must be provided that functions 
continuously when the rotorcraft is in 
a normal landing mode and the landing 
gear is not fully extended and locked. 
A manual shutoff capability must be 
provided for the warning device and the 
warning system must automatically 
reset when the rotorcraft is no longer 
in the landing mode. 

[Amdt. 27–21, 49 FR 44434, Nov. 6, 1984] 

§ 27.731

Wheels. 

(a) Each landing gear wheel must be 

approved. 

(b) The maximum static load rating 

of each wheel may not be less than the 
corresponding static ground reaction 
with— 

(1) Maximum weight; and 
(2) Critical center of gravity. 
(c) The maximum limit load rating of 

each wheel must equal or exceed the 
maximum radial limit load determined 
under the applicable ground load re-
quirements of this part. 

§ 27.733

Tires. 

(a) Each landing gear wheel must 

have a tire— 

(1) That is a proper fit on the rim of 

the wheel; and 

(2) Of the proper rating. 
(b) The maximum static load rating 

of each tire must equal or exceed the 
static ground reaction obtained at its 
wheel, assuming— 

(1) The design maximum weight; and 
(2) The most unfavorable center of 

gravity. 

(c) Each tire installed on a retract-

able landing gear system must, at the 
maximum size of the tire type expected 
in service, have a clearance to sur-
rounding structure and systems that is 
adequate to prevent contact between 

the tire and any part of the structure 
or systems. 

[Doc. No. 5074, 29 FR 15695, Nov. 24, 1964, as 
amended by Amdt. 27–11, 41 FR 55469, Dec. 20, 
1976] 

§ 27.735

Brakes. 

For rotorcraft with wheel-type land-

ing gear, a braking device must be in-
stalled that is— 

(a) Controllable by the pilot; 
(b) Usable during power-off landings; 

and 

(c) Adequate to— 
(1) Counteract any normal unbal-

anced torque when starting or stopping 
the rotor; and 

(2) Hold the rotorcraft parked on a 

10-degree slope on a dry, smooth pave-
ment. 

[Doc. No. 5074, 29 FR 15695, Nov. 24, 1964, as 
amended by Amdt. 27–21, 49 FR 44434, Nov. 6, 
1984] 

§ 27.737

Skis. 

The maximum limit load rating of 

each ski must equal or exceed the max-
imum limit load determined under the 
applicable ground load requirements of 
this part. 

F

LOATS AND

H

ULLS

 

§ 27.751

Main float buoyancy. 

(a) For main floats, the buoyancy 

necessary to support the maximum 
weight of the rotorcraft in fresh water 
must be exceeded by— 

(1) 50 percent, for single floats; and 
(2) 60 percent, for multiple floats. 
(b) Each main float must have 

enough water-tight compartments so 
that, with any single main float com-
partment flooded, the main floats will 
provide a margin of positive stability 
great enough to minimize the prob-
ability of capsizing. 

[Doc. No. 5074, 29 FR 15695, Nov. 24, 1964, as 
amended by Amdt. 27–2, 33 FR 963, Jan. 26, 
1968] 

§ 27.753

Main float design. 

(a) 

Bag floats. Each bag float must be 

designed to withstand— 

(1) The maximum pressure differen-

tial that might be developed at the 
maximum altitude for which certifi-
cation with that float is requested; and 

VerDate Sep<11>2014 

09:06 Jun 28, 2024

Jkt 262046

PO 00000

Frm 00529

Fmt 8010

Sfmt 8010

Y:\SGML\262046.XXX

262046

jspears on DSK121TN23PROD with CFR