Main landing gear wheels shall be of a type or model certificated by the Administrator in accordance with the provisions of Part 15 of this subchapter (14 F.R. 4190, July 16, 1949) and shall not be subjected to static loads in excess of those for which they are certificated. Tail wheels may be of any type or model and are not certificated. Nose wheels are subject to special rulings to be made by the Administrator.

§ 4a.478 Main landing gear wheels.

For the purpose of the regulations in this part main landing gear wheels are considered as those nearest the airplane center of gravity with respect to foreand-aft location.

§ 4a.479 Tail and nose wheels.

For the purpose of the regulations in this part, a tail wheel is considered as one which supports the tail of a conventional airplane in the three-point landing attitude. A nose wheel is considered to be a wheel supporting the nose of the airplane when the two main wheels are located behind the center of gravity. § 4a.480

Tires.

for indicating to the pilot, at all times, the position of the wheels. Separate indicators for each wheel are required when each wheel is separately operated unless a single indicator is obviously satisfactory. In addition, landplanes shall be provided with an aural or equally effective indicator which shall function continuously after the throttle is closed until the gear is down and locked.

(b) A positive lock shall be provided for the wheels in the extended position. unless a rugged irreversible mechanism is used.

(c) Manual operation of retractable landing gears shall be provided for. [Amdt. 5, 4 F. R. 1171, Mar. 9, 1939] § 4a.483-T

Brakes.

Transport category airplanes shall be equipped with brakes certificated in accordance with the provisions of Part 15 of this subchapter (14 F.R. 4190, July 16, 1949), for the maximum certificated landing weight at sea level and the power-off stalling speed, V., as defined in § 48.739-T. The brake system for such airplanes shall be so designed and constructed that in the event of a single failure in any connecting or transmitting element in the brake system, or the loss of any single source of hydraulic or other brake operating energy supply, it shall be possible, as shown by suitable test or other data, to bring the airplane to rest under the conditions specified in § 4a.750-T with a mean negative acceleration during the land roll of at least 50 percent of that obtained in determining the landing distance under that section. [Amdt. 04-6, 7 F. R. 985, Feb. 14, 1942, as amended by Amdt. 04-2, 8 F. R. 13999, Oct. 14, 1943]

least five watertight compartments of approximately equal volume. Main seaplane floats for use on aircraft of less than 2,500 pounds maximum authorized weight shall contain at least four such compartments.

§ 4a.490 Buoyancy (boat seaplanes).

The hulls of boat seaplanes and amphibians shall be divided into watertight compartments in accordance with the following requirements:

(a) In aircraft of 5,000 pounds maximum authorized weight or more the compartments shall be so arranged that, with any two adjacent compartments flooded, the hull and auxiliary floats (and tires, if used) will retain sufficient buoyancy to support the gross weight of the aircraft in fresh water.

(b) In aircraft of 1,500 to 5,000 pounds maximum authorized weight the compartments shall be so arranged that, with any one compartment flooded, the hull and auxiliary floats (and tires, if used) will retain sufficient buoyancy to support the maximum authorized weight of the aircraft in fresh water.

(c) In aircraft of less than 1,500 pounds maximum authorized weight watertight subdivision of the hull is not required.

(d) Bulkheads may have watertight doors for the purpose of communication between compartments.

Auxiliary floats shall be so arranged that when completely submerged in fresh water, they will provide a righting moment which is at least 1.5 times the upsetting moment caused by the aircraft being tilted. A greater degree of stability may be required in the case of large flying boats, depending on the height of the center of gravity above the water level, the area and location of wings and tail surfaces, and other considerations. § 4a.492 Float design.

In designing the bow portion of floats and hulls suitable provision shall be made for the effects of striking floating objects.

made to permit egress of passengers and crew in such event. The requirements of this section may be suitably modified when the possibility of a complete turnover in landing is remote.

[Amdt. 5, 4 F. R. 1171, Mar. 9, 1989] § 4a.498 External door.

Closed cabins on all aircraft carrying passengers shall be provided with at least one adequate and easily accessible external door.

§ 4a.499 Location of passenger door.

No passenger door shall be located in the plane of rotation of an inboard propeller, nor within 5 degrees thereof as measured from the propeller hub. [Amdt. 5, 4 F. R. 1171, Mar. 9, 1939]

Closed cabins on aircraft carrying more than 5 persons shall be provided with emergency exits, in addition to the one external door required by § 4a.498, consisting of movable windows or panels or of additional external doors which provide a clear and unobstructed opening, the minimum dimensions of which shall be such that a 19-inch by 26-inch ellipse may be completely inscribed therein. The location and the method of operation of emergency exits shall be approved by the Administrator. If the pilot is in a compartment separate from the cabin, passage through such compartment shall not be considered as an emergency exit for the passengers. The number of emergency exits required is as follows:

(a) Aircraft with a total seating capacity of more than 5 persons, but not in excess of 15, shall be provided with at least one emergency exit or one suitable door in addition to the main door specified in § 4a.498. This emergency exit, or second door, shall be on the opposite side of the cabin from the main door. If desired, an additional emergency exit may be provided in the top of the cabin, but such an installation shall not obviate the necessity for an exit on each side.

(b) Aircraft with a seating capacity of more than 15 persons shall be provided with an additional emergency exit or door either in the top or side of the cabin for every additional 7 persons or fraction thereof above 15, except that not more than 4 exits, including doors, will be required if the arrangement and

Means shall be provided by which the operating personnel is suitably informed of all operation information and limitations deemed necessary by the Administrator.

[Amdt. 48, 5 F. R. 1836, May 22, 1940, as amended by Amdt 75, 5 F. R. 3946, Oct. 8, 1940]

§ 4a.505 Windows and windshields.

The windows and windshields of the pilot compartment in airplanes certificated for air transportation service shall be so arranged as to provide satisfactory forward vision and protection under all conditions and, to accomplish this, particular attention shall be paid to the following detail requirements:

(a) Sufficient data specifying the windshield material, number of laminations, binder if any, size and shape of panes, angle of panes to flight path, and method and rigidity of mounting, shall be forwarded to the Administrator for rulings as to the acceptability of the windshield from the standpoint of strength.

(b) Windshields shall be so installed that they can be easily opened in flight and shall be so arranged that the air stream and snow or rain are deflected across the opening, or to provide equivalent results.

(c) The pilot compartment shall be so constructed and arranged as to prevent glare or reflections which would interfere with the vision of either pilot, particularly while flying at night. The aircraft will be flown by a representative of the Administrator during hours of darkness to determine compliance with this provision.

§ 4a.507

When a

Seats.

second pilot is required (§ 61.121 of this subchapter) two seats shall be installed side by side in the pilot compartment of airplanes certificated for air transportation service from either of which the airplane shall be fully and readily controllable. If any difference exists as to convenience of the instruments and controls necessary for safe flight such difference should favor the left-hand seat. The left-hand seat shall be known as the first pilot's seat and the right-hand one as the second pilot's seat. § 4a.508 Navigation instruments.

The navigation instruments for use by the pilot in airplanes certificated for air transportation service shall be so installed as to be easily visible to him with the minimum practicable deviation from his normal position and line of vision when he is looking out and forward along the flight path and they shall also be visible to the second pilot.

§ 4a.509 Opening between pilot compartment and passengers' cabin.

All airplanes certificated for air transportation service shall be provided with a door or an adequate openable window between the pilot compartment and the passenger cabin. When a door is provided it shall be equipped with a locking means which shall prevent passengers from opening such door while in flight.

PASSENGER AND BAGGAGE COMPARTMENTS

§ 4a.510 Passenger compartments.

A suitable ventilation system shall be provided which will preclude the presence of fuel fumes and dangerous traces of carbon monoxide in each passenger compartment.

§ 4a.511 Passenger chairs.

Seats or chairs for passengers shall be securely fastened in place in both open and closed airplanes, whether or not the safety belt load is transmitted through the seat.

CROSS REFERENCE: For safety belt requirements, see §§ 4a.193, 4a.532 (1), and 48.565. § 4a.512 Baggage compartments.

Each baggage and mail compartment shall bear a placard stating the maximum allowable weight of contents, as determined by the structural strength of the compartment (§ 4a.194) and by flight test (§ 4a.725). Suitable means shall be provided to prevent the contents of mail and baggage compartments from shifting.

REINFORCEMENT NEAR PROPELLERS

§ 4a.513 Reinforcement near propellers. Surfaces near propeller tips shall be suitably stiffened against vibration and effects of ice thrown from the propeller. CROSS REFERENCE: For clearance requirements, see § 4a.599.

Subpart F-Equipment

SOURCE: §§ 4a.523 to 4a.581 contained in Civil Air Regulations, May 31, 1938, as amended by Amendment 75, 5 F. R. 3946, Oct. 8, 1940; 24 F.R. 5, Jan. 1, 1959, except as otherwise noted.

The equipment required shall be dependent upon the type of operation for which certification is to be made. The requirements specified in this subpart shall be the basic equipment requirements and such additional equipment as may be specified in other sections of the regulations in this subchapter for specific special cases shall be supplemental hereto unless otherwise specified.

§ 4a.524 Requirements.

Each item of equipment specified in the regulations in this subchapter shall be of a type and design satisfactory to the Administrator, shall be properly installed, and shall function to the satis

faction of the Administrator. Items of equipment for which certification is required shall have been certificated in accordance with the provisions of Part 15 of this subchapter (14 F.R. 4190, July 16, 1949) or previous regulations. § 4a.524-1 Approval of aircraft components (FAA rules which apply to § 4a.524).

Aircraft components made the subject of Technical Standard Orders shall be approved upon the basis and in the manner provided in Part 514 of this title. [Supp. 9, 16 F. R. 671, Jan. 25, 1951]

(c) A tachometer for each engine. (d) An oil-pressure gauge when an oilpressure system is employed.

(e) A water thermometer for each water-cooled engine.

(f) An oil thermometer for each aircooled engine.

(g) A manifold-pressure gauge, or equivalent, for each altitude engine.

(h) A fuel quantity gauge. (See § 4a.609 for requirements.)

(i) Approved safety belts for all occupants (see § 4a.565).

(j) A portable fire extinguisher, which extinguisher shall be of an approved type, which shall have a minimum capacity, if carbon tetrachloride, of 1 quart, or, if carbon dioxide, of 2 pounds, or, if other, of equivalent effectiveness; except that any extinguisher of not less than half the above capacity may be used in an airplane equipped with an engine whose maximum rating is 40 horsepower or less. (See § 4a.566 for installation requirements.)

(k) Landing gear position indicator for retractable main landing gear. (See § 4a.482 for requirements.)

(1) A device for measuring or indicating the amount of oil in the tanks. (See § 4a.624 for requirements.)

(m) A first-aid kit.

(n) A logbook for the airplane and one for each engine. (See Part 1 of this subchapter for requirements, 14 F. R. 4034, July 16, 1949.)

(0) Rigging information for airplanes with wire-braced wings, either in the form of a sketch or listed data, which shall include sufficient information to permit proper rigging.

[CAR, May 31, 1938, as amended by Amdt. 5, 4 F. R. 1171, Mar. 9, 1939; Amdt. 116, 6 F. R. 2870, June 13, 1941; Amdt. 4a-4, 15 F. R. 29, Jan. 6, 1950]

§ 4a.533 NAC landplanes; visual contact day flying (unlimited distance). Airplanes of this category shall have the equipment specified in § 4a.532 and, in addition, there shall be installed:

(a) A magnetic compass.

CROSS REFERENCE: For installation requirements, see § 4a.562.

§ 4a.534 NAC landplanes; visual contact night flying.

Airplanes of this category shall have the equipment specified in § 4a.533 and, in addition, there shall be installed:

(a) A set of certificated standard forward position lights in combination with a certificated tail light.

CROSS REFERENCES: For light requirements, see Part 15 of this subchapter (14 F. R. 4190, July 16, 1949). For installation requirements, see § 48.578.

(b) Two electric landing lights if the aircraft is operated for hire: Provided, however, That only one such landing light shall be required for any airplane certificated for a weight of less than 1,500 pounds. (See § 4a.576 for installation requirements.)

(c) Certificated landing flares as follows, if the aircraft is operated for hire beyond an area within a circle with a radius of 3 miles drawn from the center of the airport of take-off (see Part 15 of this subchapter, 14 F. R. 4190, July 16, 1949, for flare requirements and § 4a.568 for installation requirements):

(1) Airplanes of 3,500 pounds maximum authorized weight or less-five Class 3 flares or three Class 2 flares.

(2) Airplanes of between 3,500 pounds and 5,000 pounds maximum authorized weight-four Class 2 flares.

(3) Airplanes of 5,000 pounds maximum authorized weight or more-two Class 1 flares or three Class 2 flares and one Class 1 flare.

(4) If desired, airplanes of less than 5,000 pounds maximum authorized weight may carry the flare equipment specified for heavier airplanes.

(d) A storage battery suitable as a source of energy supply for such lights and radio as are installed.

CROSS REFERENCE: For installation requirements, see § 4a.571.

(e) Radio equipment, if the aircraft is operated in a control zone (§ 60.13 of this subchapter), as follows: A radio range and weather broadcast receiver operating within the frequency range of 200 to 400 kilocycles. Under normal atmospheric conditions this receiver must be capable of receiving with a range of 100 miles intelligence emanated from a radio range or weather broadcast station the equivalent of a simultaneous Adcock range with scheduled broadcast installation.

(f) A set of spare fuses.

CROSS REFERENCE: For installation requirements, see § 4a.572.

[CAR, May 31, 1938, as amended by Amdt. 5. 4 F. R. 1171, Mar. 9, 1939]

§ 4a.535 NAC landplanes; instrument day flying.

Airplanes of this category shall have the equipment specified in § 48.533 and, in addition, there shall be installed:

(a) Radio equipment:

Same

as

§ 4a.534 (e), whether the aircraft is operated for hire or not, and, in addition, a radio transmitter operated on 3105 kilocycles with a power output sufficient to establish communication at a distance of at least 100 miles under normal atmospheric conditions. Additional frequencies may be employed subject to approval