(a) The speed VS, shall denote the calibrated stalling speed, or the minimum steady flight speed at which the airplane is controllable, in knots, with:
(1) Zero thrust at the stalling speed, or engines idling and throttles closed if it is shown that the resultant thrust has no appreciable effect on the stalling speed;
(2) If applicable, propeller pitch controls in the position necessary for compliance with subparagraph (1) of this paragraph; the airplane in all other respects (flaps, landing gear, etc.) in the particular configuration corresponding with that in connection with which VS is being used;
(3) The weight of the airplane equal to the weight in connection with which V S is being used to determine compliance with a particular requirement;
(4) The center of gravity in the most unfavorable position within the allowable range.
(b) The stall speed defined in this section shall be the minimum speed obtained in flight tests conducted in accordance with the procedure of subparagraphs (1) and (2) of this paragraph.
(1) With the airplane trimmed for straight flight at a speed of l.4 V S and from a speed sufficiently above the stalling speed to insure steady conditions, the elevator control shall be applied at a rate such that the airplane speed reduction does not exceed one knot per second.
(2) During the test prescribed in subparagraph (1) of this paragraph, the flight characteristics provisions of section 4b.160 of Part 4b of the Civil Air Regulations shall be complied with.
4T.113 Take-off; general
(a) The take-off data in sections 4T.114 through 4T.117 shall be determined under the conditions of subparagraphs (1) and (2) of this paragraph.
(1) At all weights, altitudes, and ambient temperatures within the operational limits established by the applicant for the airplane.
(2) In the configuration for take-off (see sec. 4T.111).
(b) Take-off data shall be based on a smooth, dry, hard-surfaced runway and shall be determined in such a manner that reproduction of the performance does not require exceptional skill or alertness on the part of the pilot. In the case of seaplanes or float planes, the take-off surface shall be smooth water, while for skiplanes it shall be smooth dry snow. In addition, the take-off data shall be corrected in accordance with subparagraphs (1) and (2) of this paragraph for wind and for runway gradients within the operational limits established by the applicant for the airplane.
(1) Not more than 50 percent of nominal wind components along the take-off path opposite to the direction of take-off, and not less than 150 percent of nominal wind components along the take-off path in the direction of take-off.
(2) Effective runway gradients.
4T.114 Take-off speeds.
(a) The critical-engine-failure speed V1, in terms of calibrated air speed, shall be selected by the applicant, but shall not be less than the minimum speed at which controllability by primary aerodynamic controls alone is demonstrated during the take-off run to be adequate to permit proceeding safely with the take-off using average piloting skill, when the critical engine is suddenly made inoperative.
(b) The take-off safety speed V1, in terms of calibrated air speed, shall be selected by the applicant so as to permit the gradient of climb required in section 4T.120 (a) and (b), but it shall not be less than:
(1) 1.2 VS for two-engine propeller-driven airplanes and for airplanes without propellers which have no provisions for obtaining a significant reduction in the one-engine-inoperative power-on stalling speed;
(2) 1.15 V S for propeller-driven airplanes having more than two engines and for airplanes without propellers which have provisions for obtaining a significant reduction in the one-engine-inoperative power-on stalling speed;
(3) 1.10 times the minimum control speed V MC, established in accordance with section 4b.133 of Part 4b of the Civil Air Regulations;
(4) The rotation speed V R plus the increment in speed attained in compliance with section 4T.116(e).
(c) The minimum rotation speed VR, in terms of calibrated air speed, shall be selected by the applicant, except that it shall not be less than:
(1) The speed V1;
(2) A speed equal to 95 percent of the highest speed obtained in compliance with subparagraph (1) or (2), whichever is applicable, and with subparagraph (3) of paragraph (b) of this section;
(3) A speed which permits the attainment of the Speed V 2 prior to reaching a height of 35 feet above the take-off surface as determined in accordance with section 4T.116(e);
(4) A speed equal to 110 percent of the minimum speed above which the airplane, with all engines operating, can be made to lift off the ground and to continue the take-off without displaying any hazardous characteristics.
4T.115 Accelerate-stop distance.
(a) The accelerate-stop distance shall be the sum of the following:
(1) The distance required to accelerate the airplane from a standing start to the speed V1;
(2) Assuming the critical engine to fail at the speed V1, the distance required to bring the airplane to a full stop from the point corresponding with the speed V1.
(b) In addition to, or in lieu of, wheel brakes, the use of other braking means shall be acceptable in determining the accelerate-stop distance, provided that such braking means shall have been proven to be safe and reliable, that the manner of their employment is such that consistent results can be expected in service, and that exceptional skill is not required to control the airplane.
(c) The landing gear shall remain extended throughout the accelerate-stop distance.
4T.116 Take-off path. The take-off path shall be considered to extend from the standing start to a point in the take-off where a height of 1,500 feet above the take-off surface is reached or to a point in the take-off where the transition from the take-off to the en route configuration is completed and a speed is reached at which compliance with section 4T.120(c) is shown, whichever point is at a higher altitude. The conditions of paragraphs (a) through (i) of this section shall apply in determining the take-off path.
(a) The take-off path shall be based upon procedures prescribed in accordance with section 4T.111(c).
(b) The airplane shall be accelerated on the ground to the speed V 1 at which point the critical engine shall be made inoperative and shall remain inoperative during the remainder of the take-off. Subsequent to attaining speed V1, the airplane shall be accelerated to speed V 2. during which time it shall be permissible to initiate raising the nose gear off the ground at a speed not less than the rotation speed VR.
(c) Landing gear retraction shall not be initiated until the airplane becomes airborne.
(d) The slope of the airborne portion of the take-off path shall be positive at all points.
(e) The airplane shall attain the speed V 2 prior to reaching a height of 35 feet above the take-off surface and shall continue at a speed as close as practical to, but not less than, V 2 until a height of 400 feet above the take-off surface is reached.
(f) Except for gear retraction and propeller feathering, the airplane configuration shall not be changed before reaching a height of 400 feet above the take-off surface.
(g) At all points along the take-off path starting at the point where the airplane first reaches a height of 400 feet above the take-off surface, the available gradient of climb shall not be less than 1.2 percent for two-engine airplanes and 1.7 percent for four-engine airplanes.
(h) The take-off path shall be determined either by a continuous demonstrated take-off, or alternatively, by synthesizing from segments the complete take-off path.
(i) If the take-off path is determined by the segmental method, the provisions of subparagraphs (1) through (4) of this paragraph shall be specifically applicable.
(1) The segments of a segmental take-off path shall be clearly defined and shall be related to the distinct changes in the configuration of the airplane, in power and/or thrust, and in speed.
(2) The weight of the airplane, the configuration, and the power and/or thrust shall be constant throughout each segment and shall correspond with the most critical condition prevailing in the particular segment.
(3) The segmental flight path shall be based on the airplane’s performance without ground effect.
(4) Segmental take-off path data shall be checked by continuous demonstrated takeoffs to insure that the segmental path is conservative relative to the continuous path.
4T.117 Take-off distances and take-off run.
(a) Take-off distance. The take-off distance shall be the greater of the distances established in accordance with subparagraphs (1) and (2) of this paragraph.
(1) The horizontal distance along the take-off path from the start of the take-off to the point where the airplane attains a height of 35 feet above the take-off surface, as determined in accordance with section 4T.116.
(2) A distance equal to 115 percent of the horizontal distance along the take-off path, with all engines operating, from the start of the take-off to the point where the airplane attains a height of 35 feet above the take-off surface, as determined by a procedure consistent with that established in accordance with section 4T.116.
(b) Take-off run. If the take-off distance is intended to include a clearway (see item 5 of this regulation), the take-off run shall be determined and shall be the greater of the distances established in accordance with subparagraphs (1) and (2) of this paragraph.
(1) The horizontal distance along the take-off path from the start of the take-off to a point equidistant between the point where the airplane first becomes airborne and the point where it attains a height of 35 feet above the take-off surface, as determined in accordance with section 4T.116.
(2) A distance equal to 115 percent of the horizontal distance along the take-off path, with all engines operating, from the start of the take-off to a point equidistant between the point where the airplane first becomes airborne and the point where it attains a height of 35 feet above the take-off surface, as determined by a procedure consistent with that established in accordance with section 4T.116.
4T.117a Take-off flight path.
(a) The take-off flight path shall be considered to begin at a height of 35 feet above the take-off surface at the end of the take-off distance as determined in accordance with section 4T.117(a).
(b) The net take-off flight path data shall be determined in such a manner that they represent the airplane’s actual take-off flight paths, determined in accordance with paragraph (a) of this section, diminished by a gradient of climb equal to 1.0 percent.
4T.118 Climb; general. Compliance shall be shown with the climb requirements of sections 4T.119 and 4T.120 at all weights, altitudes, and ambient temperatures, within the operational limits established by the applicant for the airplane. The airplane’s center of gravity shall be in the most unfavorable position corresponding with the applicable configuration.
4T.119 All engine-operating landing climb. In the landing configuration the steady gradient of climb shall not be less than 3.2 percent, with:
(a) All engines operating at the power and/or thrust which is available 8 seconds after initiation of movement of the power and/or thrust controls from the minimum flight idle to the take-off position;
(b) A climb speed not in excess of 1.3 VS.
4T.120 One engine-inoperative climb.
(a) Take-off; landing gear extended. In the take-off configuration existing at the point of the flight path where the airplane first becomes airborne, in accordance with section 4T.116 but without ground effect, the steady gradient of climb shall be positive for two-engine airplanes and shall not be less than 0.5 percent for four-engine airplanes, with:
(1) The critical engine inoperative, the remaining engine(s) operating at the available take-off power and/or thrust existing in accordance with section 4T.116 at the time retraction of the airplane’s landing gear is initiated, unless subsequently a more critical power operating condition exists along the flight path prior to the point where the landing gear is fully retracted;
(2) The weight equal to the airplane’s weight existing in accordance with section 4T.116 at the time retraction of the airplane’s landing gear is initiated;
(3) The speed equal to the speed V2.
(b) Take-off; landing gear retracted. In the take-off configuration existing at the point of the flight path where the airplane’s landing gear is fully retracted, in accordance with section 4T.116 but without ground effect, the steady gradient of climb shall not be less than 2.5 percent for two-engine airplanes and not less than 3.0 percent for four-engine airplanes, with:
(1) The critical engine inoperative, the remaining engine(s) operating at the available take-off power and/or thrust existing in accordance with section 4T.116 at the time the landing gear is fully retracted, unless subsequently a more critical power operating condition exists along the flight path prior to the point where a height of 400 feet above the take-off surface is reached;
(2) The weight equal to the airplane’s weight existing in accordance with section 4T.116 at the time the airplane’s landing gear is fully retracted.
(3) The speed equal to the speed V2.
(c) Final take-off. In the en route configuration, the steady gradient of climb shall not be less than 1.2 percent for two-engine airplanes and not less than 1.7 percent for four-engine airplanes, at the end of the take-off path as determined by section 4T.116, with:
(1) The critical engine inoperative, the remaining engine(s) operating at the available maximum continuous power and/or thrust;
(2) The weight equal to the airplane’s weight existing in accordance with section 4T.116 at the end of the take-off path;
(3) The speed equal to not less than 1.25 VS
(d) Approach. In the approach configuration such that the corresponding V S for this configuration does not exceed 110 percent of the V S, corresponding with the related landing configuration, the steady gradient of climb shall not be less than 2.2 percent for two-engine airplanes and not less than 2.7 percent for four-engine airplanes with:
(1) The critical engine inoperative, the remaining engine(s) operating at the available take-off power and/or thrust;
(2) The weight equal to the maximum landing weight;
(3) A climb speed established by the applicant in connection with normal landing procedures, except that it shall not exceed 1.5 VS (see sec. 4T.111(c)).
4T.121 En route flight paths. With the airplane in the en route configuration, the flight paths prescribed in paragraphs (a) and (b) of this section shall be determined at all weights, altitudes, and ambient temperatures within the limits established by the applicant for the airplane.
(a) One engine inoperative. The one-engine-inoperative net flight path data shall be determined in such a manner that they represent the airplane’s actual climb performance diminished by a gradient of climb equal to 1.1 percent for two-engine airplanes and 1.6 percent for four-engine airplanes. It shall be acceptable to include in these data the varia tion of the airplane’s weight along the flight path to take into account the progressive consumption of fuel and oil by the operating engine(s).
(b) Two engines inoperative. For airplanes with four engines, the two-engineinoperative net flight path data shall be determined in such a manner that they represent the airplane’s actual climb performance diminished by a gradient of climb equal to 0.5 percent. It shall be acceptable to include in these data the variation of the airplane’s weight along the flight path to take into account the progressive consumption of fuel and oil by the operating engines.
(c) Conditions. In determining the flight paths prescribed in paragraphs (a) and (b) of this section, the conditions of subparagraphs (1) through (4) of this paragraph shall apply.
(1) The airplane’s center of gravity shall be in the most unfavorable position.
(2) The critical engine(s) shall be inoperative, the remaining engine(s) operating at the available maximum continuous power and/or thrust.
(3) Means for controlling the engine cooling air supply shall be in the position which provides adequate cooling in the hot-day condition.
(4) The speed shall be selected by the applicant.
4T.122 Landing distance. The landing distance shall be the horizontal distance required to land and to come to a complete stop (to a speed of approximately 3 knots in the case of seaplanes or float planes) from a point at a height of 50 feet above the landing surface. Landing distances shall be determined for standard temperatures at all weights, altitudes, and winds within the operational limits established by the applicant for the airplane. The conditions of paragraphs (a) through (g) of this section shall apply.
(a) The airplane shall be in the landing configuration. During the landing, changes in the airplane’s configuration, in power and/or thrust, and in speed shall be in accordance with procedures established by the applicant for the operation of the airplane in service. The procedures shall comply with the provisions of section 4T.111(c).
(b) The landing shall be preceded by a steady gliding approach down to the 50-foot height with a calibrated air speed of not less than 1.3 VS.
(c) The landing distance shall be based on a smooth, dry, hard-surfaced runway, and shall be determined in such a manner that reproduction does not require exceptional skill or alertness on the part of the pilot. In the case of seaplanes or float planes, the landing surface shall be smooth water, while for skiplanes it shall be smooth dry snow. During landing, the airplane shall not exhibit excessive vertical acceleration, a tendency to bounce, nose over, ground loop, porpoise, or water loop.
(d) The landing distance shall be corrected for not more than 50 percent of nominal wind components along the landing path opposite to the direction of landing and not less than 150 percent of nominal wind components along the landing path in the direction of landing.
(e) During landing, the operating pressures on the wheel braking system shall not be in excess of those approved by the manufacturer of the brakes, and the wheel brakes shall not be used in such a manner as to produce excessive wear of brakes and tires.
(f) In addition to, or in lieu of, wheel brakes, the use of other braking means shall be acceptable in determining the landing distance, provided such braking means shall have been proven to be safe and reliable, that the manner of their employment is such that consistent results can be expected in service, and that exceptional skill is not required to control the airplane.
(g) If the characteristics of a device (e.g., the propellers) dependent upon the operation of any of the engines noticeably increase the landing distance when the landing is made with the engine inoperative, the landing distance shall be determined with the critical engine inoperative unless the Administrator finds that the use of compensating means will result in a landing distance not greater than that attained with all engines operating.
4T.123 Limitations and information.
(a) Limitations. The performance limitations on the operation of the airplane shall be established in accordance with subparagraphs (1) through (4) of this paragraph. (See also Sec.
4T.743.)
(1) Take-off weights. The maximum take-off weights shall be established at which compliance is shown with the generally applicable provisions of this regulation and with the take-off climb provisions prescribed in section 4T.120 (a), (b), and (c) for altitudes and ambient temperatures within the operational limits of the airplane (see subparagraph (4) of this paragraph).
(2) Landing weights. The maximum landing weights shall be established at which compliance is shown with the generally applicable provisions of this regulation and with the landing and take-off climb provisions prescribed in sections 4T.119 and 4T.120 for altitudes and ambient temperatures within the operational limits of the airplane (see subparagraph (4) of this paragraph).
(3) Accelerate-stop distance, take-off distance, and take-off run. The minimum distances required for take-off shall be established at which compliance is shown with the generally applicable provisions of this regulation and with sections 4T.115 and 4T.117(a), and with 4T.117(b) if the take-off distance is intended to include a clearway, for weights, altitudes, temperatures, wind components, and runway gradients, within the operational limits of the airplane (see subparagraph (4) of this paragraph).
(4) Operational limits. The operational limits of the airplane shall be established by the applicant for all variable factors required in showing compliance with this regulation (weight, altitude, temperature, etc.). (See secs. 4T.113 (a)(1) and (b), 4T.118, 4T.121, and 4T.122.)
(b) Information. The performance information on the operation of the airplane shall be scheduled in compliance with the generally applicable provisions of this regulation and with sections 4T.117a(b), 4T.121, and 4T.122 for weights, altitudes, temperatures, wind components,
and runway gradients, as these may be applicable, within the operational limits of the airplane (see subparagraph (a)(4) of this section). In addition, the performance information specified in subparagraphs (1) through (3) of this paragraph shall be determined by extrapolation and scheduled for the ranges of weights between the maximum landing and maximum take-off weights established in accordance with subparagraphs (a) (1) and (a) (2) of this section. (See also sec. 4T.743.)
(1) Climb in the landing configuration (see sec. 4T.119);
(2) Climb in the approach configuration (see sec. 4T.120(d));
(3) Landing distance (see sec. 4T.122).
AIRPLANE FLIGHT MANUAL 4T.743 Performance limitations, information, and. other data.
(a) Limitations. The airplane’s performance limitations shall be given in accordance with section 4T.123(a).
(b) Information. The performance information prescribed in section 4T.123(b) for the application of the operating rules of this regulation shall be given together with descriptions of the conditions, air speeds, etc., under which the data were determined.
(c) Procedures. Procedures established in accordance with section 4T.111(c) shall be given to the extent such procedures are related to the limitations and information set forth in accordance with paragraphs (a) and (b) of this section. Such procedures, in the form of guidance material, shall be included with the relevant limitations or information, as applicable.
(d) Miscellaneous. An explanation shall be given of significant or unusual flight or ground handling characteristics of the airplane.
3. In lieu of sections 40.70 through 40.78, 41.27 through 41.36(d), and 42.70 through
42.83, of Parts 40, 41, and 42 of the Civil Air Regulations, respectively, the following shall be applicable:
OPERATING RULES 40T.80 Transport category airplane operating limitations.
(a) In operating any passenger-carrying transport category airplane certificated in accordance with the performance requirements of this regulation, the provisions of sections 40T.80 through 40T.84 shall be complied with, unless deviations therefrom are specifically authorized by the Administrator on the ground that the special circumstances of a particular case make a literal observance of the requirements unnecessary for safety.
(b) The performance data in the Airplane Flight Manual shall be applied in determining compliance with the provisions of sections 40T.81 through 40T.84. Where conditions differ from those for which specific tests were made, compliance shall be determined by approved interpolation or computation of the effects of changes in the specific variables if such interpolations or computations give results substantially equaling in accuracy the results of a direct test.
40T.81 Airplane’s certificate limitations.
(a) No airplane shall be taken off at a weight which exceeds the take-off weight specified in the Airplane Flight Manual for the elevation of the airport and for the ambient temperature existing at the time of the take-off. (See secs. 4T.123(a)(1) and 4T.743(a).)
(b) No airplane shall be taken off at a weight such that, allowing for normal consumption of fuel and oil in flight to the airport of destination and to the alternate airports, the weight on arrival will exceed the landing weight specified in the Airplane Flight Manual for the elevation of each of the airports involved and for the ambient temperatures anticipated at the time of landing. (See secs. 4T.123(a) (2) and 4T.743(a).
(c) No airplane shall be taken off at a weight which exceeds the weight shown in the Airplane Flight Manual to correspond with the minimum distances required for take off. These distances shall correspond with the elevation of the airport, the runway to be used, the effective runway gradient, and the ambient temperature and wind component existing at the time of takeoff. (See secs. 4T.123(a)(3) and 4T.743(a).) If the take off distance includes a clearway as
defined in Item 5 of this regulation, the take off distance shall not include a clearway distance greater than one-half of the take-off run.
(d) No airplane shall be operated outside the operational limits specified in the Airplane Flight Manual. (See secs. 4T.123(a)(4) and 42.743(a).)
40T.82 Take-off obstacle clearance limitations. No airplane shall be taken off at a weight in excess of that shown in the Airplane Flight Manual to correspond with a net take off flight path which clears all obstacles either by at least a height of 35 feet vertically or by at least 200 feet horizontally within the airport boundaries and by at least 300 feet horizontally after passing beyond the boundaries. In determining the allowable deviation of the flight path in order to avoid obstacles by at least the distances prescribed, it shall be assumed that the airplane is not banked before reaching a height of 50 feet as shown by the take-off path data in the Airplane Flight Manual, and that a maximum bank thereafter does not exceed 15 degrees. The take-off path considered shall be for the elevation of the airport, the effective runway gradient, and for the ambient temperature and wind component existing at the time of take off. (See secs. 4T.123(b) and 4T.743(b).)
40T.83 En route limitations.
(a) One engine inoperative. No airplane shall be taken off at a weight in excess of that which, according to the one-engine-inoperative en route net flight path data shown in the Airplane Flight Manual, will permit compliance with either subparagraph (1) or subparagraph (2) of this paragraph at all points along the route. The net flight path used shall be for the ambient temperatures anticipated along the route. (See secs. 4T.123(b) and 4T.743(b).)
(1) The slope of the net flight path shall be positive at an altitude of at least 1,000 feet above all terrain and obstructions along the route within 5 miles on either side of the intended track.
(2) The net flight path shall be such as to permit the airplane to continue flight from the cruising altitude to an alternate airport where a landing can be made in accordance with the provisions of section 40T.84(b), the net flight path clearing vertically by at least 2,000 feet all terrain and obstructions along the route within 5 miles on either side of the intended track. The provisions of subdivisions (i) through (vii) of this subparagraph shall apply.
(i) The engine shall be assumed to fail at the most critical point along the route.
(ii) The airplane shall be assumed to pass over the critical obstruction following engine failure at a point no closer to the critical obstruction than the nearest approved radio navigational fix, except that the Administrator may authorize a procedure established on a different basis where adequate operational safeguards are found to exist.
(iii) The net flight path shall have a positive slope at 1,500 feet above the airport used as the alternate.
(iv) An approved method shall be used to account for winds which would otherwise adversely affect the flight path.
(v) Fuel jettisoning shall be permitted if the Administrator finds that the operator has an adequate training program, proper instructions are given to the flight crew, and all other precautions are taken to insure a safe procedure.
(vi) The alternate airport shall be specified in the dispatch release and shall meet the prescribed weather minima.
(vii) The consumption of fuel and oil after the engine becomes inoperative shall be that which is accounted for in the net flight path data shown in the Airplane Flight Manual.
(b) Two engines inoperative. No airplane shall be flown along an intended route except in compliance with either subparagraph (1) or subparagraph (2) of this paragraph.
(1) No place along the intended track shall be more than 90 minutes away from an airport at which a landing can be made in accordance with the provisions of section 4OT.84(b), assuming all engines to be operating at cruising power.
(2) No airplane shall be taken off at a weight in excess of that which, according to the two-engine-inoperative en route net flight path data shown in the Airplane Flight Manual, will permit the airplane to continue flight from the point where two engines are assumed to fail simultaneously to an airport where a landing can be made in accordance with the provisions of section 40T.84(b), the net flight path having a positive slope at an altitude of at least 1,000 feet above all terrain and obstructions along the route within 5 miles on either side of the intended track or at an altitude of 2,000 feet, whichever is higher. The net flight path considered shall be for the ambient temperatures anticipated along the route. The provisions of subdivisions (i) through (iii) of this subparagraph shall apply. (See secs. 4T.123(b) and 4T.743(b).)
(i) The two engines shall be assumed to fail at the most critical point along the route.
(ii) The airplane’s weight at the point where the two engines are assumed to fail shall be considered to be not less than that which would include sufficient fuel to proceed to the airport and to arrive there at an altitude of at least 1,500 feet directly over the landing area and thereafter to fly for 15 minutes at cruise power and/or thrust
(iii) The consumption of fuel and oil after the engines become inoperative shall be that which is accounted for in the net flight path data shown in the Airplane Flight Manual.
40T.84 Landing limitations.
(a) Airport of destination. No airplane shall be taken off at a weight in excess of that which, in accordance with the landing distances shown in the Airplane Flight Manual for the elevation of the airport of intended destination and for the wind conditions anticipated there at the time of landing, would permit the airplane to be brought to rest at the airport of intended destination within 60 percent of the effective length of the runway from a point 50 feet directly above the intersection of the obstruction clearance plane and the runway. The weight of the airplane shall be assumed to be reduced by the weight of the fuel and oil expected to be consumed in flight to the airport of intended destination. Compliance shall be shown with the conditions of subparagraphs (1) and (2) of this paragraph. (See secs. 4T.123(b) and 4T.743(b).)
(1) It shall be assumed that the airplane is landed on the most favorable runway and direction in still air.
(2) It shall be assumed that the airplane is landed on the most suitable runway considering the probable wind velocity and direction and taking due account of the ground handling characteristics of the airplane and of other conditions (i.e., landing aids, terrain, etc.). If full compliance with the provisions of this subparagraph is not shown, the airplane may be taken off if an alternate airport is designated which permits compliance with paragraph (b) of this section.
(b) Alternate airport. No airport shall be designated as an alternate airport in a dispatch release unless the airplane at the weight anticipated at the time of arrival at such airport can comply with the provisions of paragraph (a) of this section, provided that the airplane can be brought to rest within 70 percent of the effective length of the runway.
4. In lieu of section 43.11 of Part 43 of the Civil Air Regulations, the following shall be applicable:
43T.11 Transport category airplane weight limitations. The performance data in the Airplane Flight Manual shall be applied in determining compliance with the following provisions:
(a) No airplane shall be taken off at a weight which exceeds the take-off weight specified in the Airplane Flight Manual for the elevation of the airport and for the ambient temperature existing at the time of the take-off. (See secs. 4T.123(a) (1) and 4T.743(a).)
(b) No airplane shall be taken off at a weight such that, allowing for normal consumption of fuel and oil in flight to the airport of destination and to the alternate airports, the weight on arrival will exceed the landing weight specified in the Airplane Flight Manual for the elevation of each of the airports involved and for the ambient temperatures anticipated at the time of landing. (See secs. 4T.123(a) (2) and 4T.743(a).)
(c) No airplane shall be taken off at a weight which exceeds the weight shown in the Airplane Flight Manual to correspond with the minimum distances required for take-off. These distances shall correspond with the elevation of the airport, the runway to be used, the effective runway gradient, and the ambient temperature and wind component existing at the time of takeoff. (See secs. 4T.123(a)(3) and 4T.743(a).) If the take-off distance includes a clearway as defined in Item 5 of this regulation, the take-off distance shall not include a clearway distance greater than one-half of the take-off run.
(d) No airplane shall be operated outside the operational limits specified in the Airplane Flight Manual. (See secs. 4T.123(a) (4) and 4T.743(a).)
5. The following definitions shall apply:
Clearway. A clearway is an area beyond the airport runway not less than 300 feet on either side of the extended center line of the runway, at an elevation no higher than the elevation at the end of the runway, clear of all fixed obstacles, and under the control of the airport authorities.
SPECIAL CIVIL AIR REGULATION NO. SR-422B Effective: July 9, 1959 Issued: July 9. 1959 Turbine Powered Transport Category Airplane of Current Design Special Civil Air Regulation No. SR-422, effective August 27, 1957, prescribes requirements applicable to the type certification and operation of turbine-powered transport category airplanes for which a type certificate is issued after August 27, 1957. Special Civil Air Regulation No. SR-422A, effective July 2, 1958, included substantive changes to SR-422 and was made applicable to all turbine-powered transport category airplanes for which a type certificate is issued after September 30, 1958.
This Special Civil Air Regulation makes further changes to the airworthiness rules for turbine-powered transport category airplanes to be applicable to all such airplanes for which a type certificate is issued after August 29, 1959. These changes were proposed in Draft Release No.58-1 C (24 F.R. 128) by the Civil Aeronautics Board in connection with the 1958 Annual Airworthiness Review. The amendments herein have been adopted after careful consideration of all the discussion and comment received thereon.
Substantive and minor changes have been made to the provisions of SR-422A. For ease in identification they are listed as follows:
(a) Substantive changes: introductory paragraphs; 4T.114 (b), (c), (d), (e), and (f);
4T.115(d); 4T.117a(b); 4T.120(a)(3), (b), and (d); 40T.81(c) ; 43T.11(c); and item 5 (a) and (b).
(b) Minor changes; item 2; 4T.112 (title), (b)(1), (c), (d), and (e); 4T.113(b);
4T.116(i)(4); 4T.117(b) (1) and (2); 4T.120(a); 4T.121; 4T.122(d) ; 4T.123(a); 40T.82; and 40T.83.
Pertinent background information to this regulation is contained in the preambles to SR- 422 and SR-422A. Following is a discussion of important issues relevant to the changed provisions contained herein.
One of the most important changes being introduced concerns the rotation speed V R of the airplane during takeoff (4T.114). Experience gained in the certification of airplanes under the provisions of SR-422 and SR-422A indicates that relating V R to the stall speed is not essential and might unduly penalize airplanes with superior flying qualities. It has been found that the primary limitations on V R should be in terms of a margin between the actual lift-off speeds VLOF and the minimum unstick speed V MU at which the airplane can proceed safely with the takeoff. The provisions contained herein require that V R speeds be established to be applicable to takeoffs with one engine inoperative as well as with all engines operating. The VMU speeds can be established from free air data provided that the data are verified by ground takeoff tests. Certain safeguards are included in conjunction with the establishment of VR speeds to ensure that takeoffs in service can be made with consistent safety.
A change is being introduced to the provision in 4T.117a(b) concerning the manner in which the net takeoff flight path is obtained. In accordance with this provision as contained in SR-422A, the net takeoff flight path would have a negative slope throughout the acceleration segment. Since this segment usually represents level flight easily controlled by reference to the normal flight instruments, a significant reduction in the flight path’s gradient would not be expected. For these reasons, the provision is being changed to permit an equivalent reduction in acceleration in lieu of a reduction in gradient.
Section 4T.117a(b) is being amended additionally by changing the value of gradient margin in the net flight path for two-engine airplanes from 1.0 percent to 0.8 percent. The value for four engine airplanes remains 1.0 percent. Differentiation in gradient values in the net flight path between two and four-engine airplanes is consistent with the differentiation in the climb gradients for the takeoff, enroute, and approach stages of flight. Statistical analysis substantiates