airborne portion of the takeoff to the 50-foot height should not exceed that used for the "normal climb condition" of §3.85 (a). However, if the applicant so desires, he may enter additional take-off data in the Airplane Flight Manual in which the flap setting specified in § 3.84 or § 3.85 (a) has been exceeded, provided the portion of the flight path beyond the 50-foot point which will cover the transition to normal climb configuration of § 3.85 (a), is also included. [Supp. 10, 16 F. R. 3283, Apr. 14, 1951] § 3.84-2 Measurement of seaplane takeoff distances (FAA interpretations which apply to § 3.84(a)).

The standard starting point for the measurement of seaplane take-off distances may be assumed to be the point at which the seaplane has attained an initial speed of three miles per hour during take-off.

[Supp. 10, 16 F. R. 3283, Apr. 14, 1951] § 3.84-3 Take-off speed (FAA interpretations which apply to § 3.84(b)).

1.3 XV., or V.+5 speed should be used for take-off even if throttling back is necessary to prevent exceeding r. p. m. limits.

Supp. 10, 16 F. R. 3283, Apr. 14, 1951] § 3.84a Take-off requirements; planes of 6,000 lbs. or less.

air

Airplanes having a maximum certificated take-off weight of 6,000 lbs. or less shall comply with the provisions of this section.

(a) The elevator control for tail wheel type airplanes shall be sufficient to maintain at a speed equal to 0.8 Vs, an airplane attitude which will permit holding the airplane on the runway until a safe take-off speed is attained.

(b) The elevator control for nose wheel type airplanes shall be sufficient to raise the nose wheel clear of the takeoff surface at a speed equal to 0.85 V.

(c) The characteristics prescribed in paragraphs (a) and (b) of this section shall be demonstrated with:

(1) Take-off power,

(2) Most unfavorable weight,

(3) Most unfavorable c. g. position.

(d) It shall be demonstrated that the airplane will take off safely without requiring an exceptional degree of piloting skill.

§3.85 Climb.

CLIMB

The

(a) Normal climb condition. steady rate of climb at sea level shall be at least 300 feet per minute, and the steady angle of climb at least 1:12 for landplanes or 1:15 for seaplanes with: (1) Not more than maximum continuous power on all engines,

(2) Landing gear fully retracted, (3) Wing flaps in take-off position, (4) Cowl flaps in the position used in cooling tests specified in §§ 3.581-3.596.

(b) Climb with inoperative engine. All multiengine airplanes having a stalling speed Vs, greater than 70 miles per hour or a maximum weight greater than 6,000 pounds shall have a steady rate of climb of at least 0.02 V ̧3 in feet per minute at an altitude of 5,000 feet with the critical engine inoperative and:

2

(1) The remaining engines operating at not more than maximum continuous power,

(2) The inoperative propeller in the minimum drag position,

(3) Landing gear retracted,

(4) Wing flaps in the most favorable position,

(5) Cowl flaps in the position used in cooling tests specified in §§ 3.581-3.596.

(c) Balked landing conditions. The steady angle of climb at sea level shall be at least 1:30 with:

(1) Take-off power on all engines,
(2) Landing gear extended,

(3) Wing flaps in landing position. If rapid retraction is possible with safety without loss of altitude and without requiring sudden changes of angle of attack or exceptional skill on the part of the pilot, wing flaps may be retracted.

§ 3.85-1 Rate of climb (FAA policies which apply to § 3.85).

To meet the requirements of § 3.85 it is necessary that a suitable method be employed for the purpose of determining the rates of climb. The Administrator will accept the following procedure for this purpose:

This method of obtaining rates of climb is through the derivation of a polar curve obtained from a series of sawtooth climbs at various speeds. When saw-tooth climbs are employed, a minimum of five different speeds is required.

However, demonstration climbs to prove the article meets the minimum climb requirement may be made at one given air speed. In such cases, the minimum number of climbs at one air speed shall be not less than three. This may not be interpreted to mean the best three of a number of climbs. In the event additional climbs are made the average of the total shall be the value to be accepted. It shall be permissible, however, to discard any climbs which are obviously in error due to such factors as turbulent air.

[Supp. 1, 12 F. R. 3434, May 28, 1947, as amended by Amdt. 1, 14 F. R. 36, Jan. 5, 1949]

§ 3.85-2

"Normal climb" and "cooling test procedure for single-engine airplanes" (FAA interpretations which apply to § 3.85).

In connection with any application to have an aircraft certified for airworthiness under a combination of the requirements of this part and Part 4a of this subchapter as authorized by the provisions of § 3.2, the items of "normal climb" (§ 3.85(a)) and "cooling test procedure for single-engine airplanes” (§ 3.586), shall be construed by the Administrator as "related items."

[Supp. 1, 12 F. R. 3435, May 28, 1947, as amended by Amdt. 1, 14 F. R. 36, Jan. 5, 1949]

§ 3.85-3 "Rapid retraction" (FAA in

terpretations which apply to § 3.85). The Administrator will consider retraction of flaps in 2 seconds or less as compliance with the factor of "rapid retraction" as that phrase is used in § 3.85 (c).

[Supp. 1, 12 F. R. 3435, May 28, 1947, as amended by Amdt. 1, 14 F. R. 36, Jan. 5, 1949]

§ 3.85-4 Weight for items of performance and flight characteristics (FAA interpretations which apply to

§ 3.85).

For multiengine airplanes in which the design landing weight (§ 3.242) is less than the maximum weight (§ 3.74) for which certification is desired, the weight for items of performance and flight characteristics shall be construed by the Administrator as the maximum weight defined in § 3.74. Such items of performance and flight characteristics shall consist of balked landing (climb) conditions (§3.74), landing over 50-foot obstacles (§ 3.86), and all flight charac

teristics tests in the landing configuration. The design weight covered in § 3.242 is intended for use for structural design purposes only.

[Supp. 1, 12 F. R. 3435, May 28, 1947, as amended by Amdt. 1, 14 F. R. 36, Jan 5, 1949]

§ 3.85-5 Low-pitch propeller_setting in normal climb position (FAA interpretations which apply to § 3.85 (a)). (a) In the event an airplane has:

(1) An engine for which the take-off and maximum continuous power ratings are identical, and

(2) A fixed-pitch, two-position or similar type propeller,

then the regulations provide that the best rate of climb speed specified in §3.85 (a) for normal climb should be determined with the low-pitch propeller setting which would restrain the engine to an r. p. m. at full throttle not exceeding its permissible take-off r. p. m. (see § 3.419 (a)).

(b) A relaxation of the propeller pitch setting requirement stipulated by § 3.419 (a) may be granted, however, for an airplane falling into the foregoing classification, when it shows a marginal item of performance as, for example, when it can meet the rate of climb requirement of § 3.85 (a) for normal climb, but may have difficulty in meeting the angle of climb requirements of § 3.85 (a) for normal climb and/or § 3.85 (c) for balked landing. In this case, it will be permissible to use a lower propeller pitch setting than specified in § 3.419 (a), in order to obtain rated engine r. p. m. at the best angle of climb speed: Provided, Acceptable engine cooling can be demonstrated at the lower speed associated with the best angle of climb. In employing this procedure, consideration should also be given to the following:

(1) That the best angle of climb speed for the balked landing condition may be considerably lower than the best angle of climb speed for the normal climb condition.

(2) That as a result of subparagraph (1) of this paragraph, the engine would normally have to be part throttled to avoid exceeding rated r. p. m. at the higher speeds, and would therefore develop less than rated power for showing compliance with the normal climb and take-off requirements of §§ 3.85 (a) and 3.84, respectively.

[Supp. 10, 16 F. R. 3283. Apr. 14, 1951]

§ 3.85a

Climb requirements; airplanes of 6,000 lbs. or less.

Airplanes having a maximum certificated take-off weight of 6,000 lbs. or less shall comply with the requirements of this section.

(a) Climb; take-off climb condition. The steady rate of climb at sea level shall not be less than 10 V11 or 300 feet per minute, whichever is the greater, with: (1) Take-off power,

(2) Landing gear extended,

(3) Wing flaps in take-off position,

(4) Cowl flaps in the position used in cooling tests specified in §§ 3.581 through 3.596.

(b) Climb with inoperative engine. All multiengine airplanes having a stalling speed Vs, greater than 70 miles per hour shall have a steady rate of climb of at least 0.02 Vo' in feet per minute at an altitude of 5,000 feet with the critical : engine inoperative and:

2

(1) Immediately prior to reaching the 50-foot altitude, a steady gliding approach shall have been maintained, with a true indicated air speed of at least 1.5V1.

nose

(2) The landing shall be made in such a manner that there is no excessive vertical acceleration, no tendency to bounce, over, ground loop, porpoise, or water loop, and in such a manner that its reproduction shall not require any exceptional degree of skill on the part of the pilot or exceptionally favorable conditions.

(b) The distance so obtained, the type of landing surface on which made and the pertinent information with respect to cowl flap position, and the use of flight path control devices shall be entered in the Airplane Flight Manual.

[21 F.R. 3339, May 22, 1956, as amended by Amdt. 3-5, 24 F.R. 7066, Sept. 1, 1959]

§ 3.86-1 Landing distances (FAA policies which apply to § 3.86).

The Administrator will not approve the use of landing distances obtainable with reverse-thrust propellers in establishing landing field lengths until such time as sufficient experience with their use is available for proper consideration of all related factors involved in the establishment of adequate airport lengths for routine landings.

[Supp. 1, 12 F. R. 8487, May 28, 1947, as amended by Amdt. 1, 14 F. R. 36, Jan. 5, 1949]

§ 3.86-2 Use of camera equipment (FAA policies which apply to § 3.86). The landing distance should be determined photographically. FAA camera equipment is available on a loan basis. [Supp. 10, 16 F. R. 3284, Apr. 14, 1951]

§ 3.87 Landing requirements; airplanes of 6,000 lbs. or less.

For an airplane having a maximum certificated take-off weight of 6,000 lbs. or less it shall be demonstrated that the airplane can be safely landed and brought to a stop without requiring an exceptional degree of piloting skill, and without excessive vertical acceleration, tendency to bounce, nose over, ground loop, porpoise, or water loop. FLIGHT CHARACTERISTICS

The airplane shall be satisfactorily controllable and maneuverable during take-off, climb, level flight, dive, and landing with or without power. It shall be possible to make a smooth transition from one flight condition to another, including turns and slips, without requiring an exceptional degree of skill, alertness, or strength on the part of the pilot, and without danger of exceeding the limit load factor under all conditions of operation probable for the type, including for multiengine airplanes those conditions normally encountered in the event of sudden failure of any engine. Compliance with "strength of pilots" limits need not be demonstrated by quantitative tests unless the Administrator finds the condition to be marginal. In the latter case they shall not exceed maximum values found by the Administrator to be appropriate for the type but in no case shall they exceed the following limits:

(1) Maximum continuous power on all engines, the airplane trimmed at VI.

(2) Power-off and the airplane trimmed at 1.5 Vs, or at the minimum speed, whichever is higher.

(3) (i) Wing flaps and landing gear extended and

(ii) Wing flaps and landing gear reracted.

(b) During each of the controllability demonstrations outlined below it shall not require a change in the trim control or the exertion of more control force than can be readily applied with one hand for a short period. Each maneuver shall be performed with the landing gear extended.

(1) With power off, flaps retracted, and the airplane trimmed as prescribed in paragraph (a) (2) of this section, the flaps shall be extended as rapidly as possible while maintaining the air speed at approximately 40 percent above the instantaneous value of the stalling speed. }

(2) Same as subparagraph (1) of this paragraph, except the flaps shall be initially extended and the airplane trimmed as prescribed in paragraph (a) (2) of this section, then the flaps shall be retracted as rapidly as possible.

(3) Same as subparagraph (2) of this paragraph, except maximum continuous power shall be used.

(4) With power off, the flaps retracted, and the airplane trimmed as prescribed in paragraph (a) (2) of this section, take-off power shall be applied quickly while the same air speed is maintained.

(5) Same as subparagraph (4) of this paragraph, except with the flaps extended.

(6) With power off, flaps extended, and the airplane trimmed as prescribed in paragraph (a) (2) of this section, air speeds within the range of 1.1 Vs, to 1.7 Vs1 or V1, whichever is the lesser, shall be obtained and maintained.

(c) It shall be possible without the use of exceptional piloting skill to maintain essentially level flight when flap retraction from any position is initiated during steady horizontal flight at 1.1 V11 with simultaneous application of not more than maximum continuous power.

(d) It shall be possible to maintain a speed of not more than 1.5 Vs, with a pilot control force of not more than 10

pounds during a power-off glide with landing gear and wing flaps extended, with the most forward center of gravity position approved at the maximum weight, and regardless of weight.

(e) It shall be possible, without the use of the primary means of longitudinal control, to control the descent of the airplane with the use of all other normal flight and power controls to a zero rate of descent and to an attitude suitable for a controlled landing without requiring ex=ceptional strength, skill, or alertness on the part of the pilot, or without exceeding the operational and the structural limitations of the airplane.

[21 F.R. 3339, May 22, 1956, as amended by Amdt. 3-5, 24 F.R. 7066, Sept. 1, 1959] §3.110 Lateral and directional control.

(a) It shall be possible with multiengine airplanes to execute 15-degree banked turns both with and against the inoperative engine from steady climb at 1.4 Vs, or Vy for the condition with:

(1) Maximum continuous power on the operating engines,

(2) Rearmost center of gravity,
(3) (i) Landing gear retracted and
(ii) Landing gear extended.

(4) Wing flaps in most favorable climb position,

(5) Maximum weight,

(6) The inoperative propeller in its minimum drag condition.

(b) It shall be possible with multiengine airplanes, while holding the wings level laterally within 5 degrees, to execute sudden changes in heading in both directions without dangerous characteristics being encountered. This shall be demonstrated at 1.4 Vs, or V, up to heading changes of 15 degrees, except that the heading change at which the rudder force corresponds to that specified in § 3.106 need not be exceeded, with:

(1) The critical engine inoperative, (2) Maximum continuous power on the operating engine(s),

(3) (i) Landing gear retracted and (ii) Landing gear extended,

(4) Wing flaps in the most favorable climb position,

(5) The inoperative propeller in its minimum drag condition,

(6) The airplane center of gravity at its rearmost position.

§ 3.111 Minimum control speed (Vmo).

(a) A minimum speed shall be determined under the conditions specified below, such that when any one engine is suddenly made inoperative at that speed, it shall be possible to recover control of the airplane, with the one engine still inoperative, and to maintain it in straight flight at that speed, either with zero yaw or, at the option of the applicant, with a bank not in excess of 5 degrees. Such speed shall not exceed 1.2 V.1 with:

(1) Take-off or maximum available power on all engines,

(2) Rearmost center of gravity,
(3) Flaps in take-off position,
(4) Landing gear retracted.

(b) In demonstrating this minimum speed, the rudder force required to maintain it shall not exceed forces specified in § 3.106, nor shall it be necessary to throttle the remaining engines. During recovery the airplane shall not assume any dangerous attitude, nor shall it require exceptional skill, strength, or alertness on the part of the pilot to prevent a change of heading in excess of 20 degrees before recovery is complete. [21 F.R. 3339, May 22, 1956, as amended by Amdt. 3-2, 22 F.R. 5561, July 16, 1957]

(a) The means used for trimming the airplane shall be such that, after being trimmed and without further pressure upon or movement of either the primary control or its corresponding trim control by the pilot or the automatic pilot, the airplane will maintain:

(1) Lateral and directional trim in level flight at a speed of 0.9 Vn or at Vc, if lower, with the landing gear and wing flaps retracted;

(2) Longitudinal trim under the following conditions:

(i) During a climb with maximum continuous power at a speed between VI and 1.4 Vs1,

(a) With landing gear retracted and wing flaps retracted,

(b) With landing gear retracted and wing flaps in the take-off position.

(ii) During a power approach at 1.5 V11 and while maintaining a 3-degree angle of descent.