title-14-part-25-sec25-771

276

14 CFR Ch. I (1–1–24 Edition)

§ 25.737

(3)

Most severe landing stop. The most

severe landing stop is a stop at the
most critical combination of airplane
landing weight and speed. The most se-
vere landing stop brake kinetic energy
absorption requirement of each wheel,
brake, and tire assembly must be de-
termined. It must be substantiated by
dynamometer testing that, at the de-
clared fully worn limit(s) of the brake
heat sink, the wheel, brake and tire as-
sembly is capable of absorbing not less
than this level of kinetic energy. The
most severe landing stop need not be
considered for extremely improbable
failure conditions or if the maximum
kinetic energy accelerate-stop energy
is more severe.

(g)

Brake condition after high kinetic

energy dynamometer stop(s). Following
the high kinetic energy stop dem-
onstration(s) required by paragraph (f)
of this section, with the parking brake
promptly and fully applied for at least
3 minutes, it must be demonstrated
that for at least 5 minutes from appli-
cation of the parking brake, no condi-
tion occurs (or has occurred during the
stop), including fire associated with
the tire or wheel and brake assembly,
that could prejudice the safe and com-
plete evacuation of the airplane.

(h)

Stored energy systems. An indica-

tion to the flightcrew of the usable
stored energy must be provided if a
stored energy system is used to show
compliance with paragraph (b)(1) of
this section. The available stored en-
ergy must be sufficient for:

(1) At least 6 full applications of the

brakes when an antiskid system is not
operating; and

(2) Bringing the airplane to a com-

plete stop when an antiskid system is
operating, under all runway surface
conditions for which the airplane is
certificated.

(i)

Brake wear indicators. Means must

be provided for each brake assembly to
indicate when the heat sink is worn to
the permissible limit. The means must
be reliable and readily visible.

(j)

Overtemperature burst prevention.

Means must be provided in each braked
wheel to prevent a wheel failure, a tire
burst, or both, that may result from
elevated brake temperatures. Addition-
ally, all wheels must meet the require-
ments of § 25.731(d).

(k)

Compatibility. Compatibility of

the wheel and brake assemblies with
the airplane and its systems must be
substantiated.

[Doc. No. FAA–1999–6063, 67 FR 20420, Apr. 24,
2002, as amended by Amdt. 25–108, 67 FR
70827, Nov. 26, 2002; 68 FR 1955, Jan. 15, 2003]

§ 25.737

Skis.

Each ski must be approved. The max-

imum limit load rating of each ski
must equal or exceed the maximum
limit load determined under the appli-
cable ground load requirements of this
part.

LOATS AND

ULLS

§ 25.751

Main float buoyancy.

Each main float must have—
(a) A buoyancy of 80 percent in excess

of that required to support the max-
imum weight of the seaplane or am-
phibian in fresh water; and

(b) Not less than five watertight com-

partments approximately equal in vol-
ume.

§ 25.753

Main float design.

Each main float must be approved

and must meet the requirements of
§ 25.521.

§ 25.755

Hulls.

(a) Each hull must have enough wa-

tertight compartments so that, with
any two adjacent compartments flood-
ed, the buoyancy of the hull and auxil-
iary floats (and wheel tires, if used)
provides a margin of positive stability
great enough to minimize the prob-
ability of capsizing in rough, fresh
water.

(b) Bulkheads with watertight doors

may be used for communication be-
tween compartments.

ERSONNEL AND

ARGO

CCOMMODATIONS

§ 25.771

Pilot compartment.

(a) Each pilot compartment and its

equipment must allow the minimum
flight crew (established under § 25.1523)
to perform their duties without unrea-
sonable concentration or fatigue.

(b) The primary controls listed in

§ 25.779(a), excluding cables and control
rods, must be located with respect to

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§ 25.773

the propellers so that no member of the
minimum flight crew (established
under § 25.1523), or part of the controls,
lies in the region between the plane of
rotation of any inboard propeller and
the surface generated by a line passing
through the center of the propeller hub
making an angle of five degrees for-
ward or aft of the plane of rotation of
the propeller.

pilot, the airplane must be controllable
with equal safety from either pilot
seat.

(d) The pilot compartment must be

constructed so that, when flying in
rain or snow, it will not leak in a man-
ner that will distract the crew or harm
the structure.

(e) Vibration and noise characteris-

tics of cockpit equipment may not
interfere with safe operation of the air-
plane.

[Doc. No. 5066, 29 FR 18291, Dec. 24, 1964, as
amended by Amdt. 25–4, 30 FR 6113, Apr. 30,
1965]

§ 25.772

Pilot compartment doors.

For an airplane that has a lockable

door installed between the pilot com-
partment and the passenger compart-
ment:

(a) For airplanes with a maximum

passenger seating configuration of
more than 20 seats, the emergency exit
configuration must be designed so that
neither crewmembers nor passengers
require use of the flightdeck door in
order to reach the emergency exits pro-
vided for them; and

(b) Means must be provided to enable

flight crewmembers to directly enter
the passenger compartment from the
pilot compartment if the cockpit door
becomes jammed.

means to enable a flight attendant to
enter the pilot compartment in the
event that the flightcrew becomes in-
capacitated.

[Doc. No. 24344, 55 FR 29777, July 20, 1990, as
amended by Amdt. 25–106, 67 FR 2127, Jan. 15,
2002]

§ 25.773

Pilot compartment view.

(a)

Nonprecipitation conditions. For

nonprecipitation conditions, the fol-
lowing apply:

(1) Each pilot compartment must be

arranged to give the pilots a suffi-
ciently extensive, clear, and undis-
torted view, to enable them to safely
perform any maneuvers within the op-
erating limitations of the airplane, in-
cluding taxiing takeoff, approach, and
landing.

(2) Each pilot compartment must be

free of glare and reflection that could
interfere with the normal duties of the
minimum flight crew (established
under § 25.1523). This must be shown in
day and night flight tests under non-
precipitation conditions.

(b)

Precipitation conditions. For pre-

cipitation conditions, the following
apply:

(1) The airplane must have a means

to maintain a clear portion of the
windshield, during precipitation condi-
tions, sufficient for both pilots to have
a sufficiently extensive view along the
flight path in normal flight attitudes
of the airplane. This means must be de-
signed to function, without continuous
attention on the part of the crew, in—

(i) Heavy rain at speeds up to 1.5 V

SR1

with lift and drag devices retracted;
and

(ii) The icing conditions specified in

Appendix C of this part and the fol-
lowing icing conditions specified in Ap-
pendix O of this part, if certification
for flight in icing conditions is sought:

(A) For airplanes certificated in ac-

cordance with § 25.1420(a)(1), the icing
conditions that the airplane is certified
to safely exit following detection.

(B) For airplanes certificated in ac-

cordance with § 25.1420(a)(2), the icing
conditions that the airplane is certified
to safely operate in and the icing con-
ditions that the airplane is certified to
safely exit following detection.

cordance with § 25.1420(a)(3) and for air-
planes not subject to § 25.1420, all icing
conditions.

(2) No single failure of the systems

used to provide the view required by
paragraph (b)(1) of this section must
cause the loss of that view by both pi-
lots in the specified precipitation con-
ditions.

(3) The first pilot must have a win-

dow that—

(i) Is openable under the conditions

prescribed in paragraph (b)(1) of this