14 CFR 23.45 - General.
(a) Unless otherwise prescribed, the performance requirements of this part must be met for -
(1) Still air and standard atmosphere; and
(b) Performance data must be determined over not less than the following ranges of conditions -
(1) Airport altitudes from sea level to 10,000 feet; and
(2) For reciprocating engine-powered airplanes of 6,000 pounds, or less, maximum weight, temperature from standard to 30 °C above standard; or
(3) For reciprocating engine-powered airplanes of more than 6,000 pounds maximum weight and turbine engine-powered airplanes, temperature from standard to 30 °C above standard, or the maximum ambient atmospheric temperature at which compliance with the cooling provisions of § 23.1041 to § 23.1047 is shown, if lower.
(c) Performance data must be determined with the cowl flaps or other means for controlling the engine cooling air supply in the position used in the cooling tests required by §§ 23.1041 to 23.1047.
(d) The available propulsive thrust must correspond to engine power, not exceeding the approved power, less -
(1) Installation losses; and
(2) The power absorbed by the accessories and services appropriate to the particular ambient atmospheric conditions and the particular flight condition.
(e) The performance, as affected by engine power or thrust, must be based on a relative humidity:
(1) Of 80 percent at and below standard temperature; and
(2) From 80 percent, at the standard temperature, varying linearly down to 34 percent at the standard temperature plus 50 °F.
(f) Unless otherwise prescribed, in determining the takeoff and landing distances, changes in the airplane's configuration, speed, and power must be made in accordance with procedures established by the applicant for operation in service. These procedures must be able to be executed consistently by pilots of average skill in atmospheric conditions reasonably expected to be encountered in service.
(g) The following, as applicable, must be determined on a smooth, dry, hard-surfaced runway -
(2) Accelerate-stop distance of § 23.55;
(4) Landing distance of § 23.75.
The effect on these distances of operation on other types of surfaces (for example, grass, gravel) when dry, may be determined or derived and these surfaces listed in the Airplane Flight Manual in accordance with § 23.1583(p).
(h) For multiengine jets weighing over 6,000 pounds in the normal, utility, and acrobatic category and commuter category airplanes, the following also apply:
(3) Unless otherwise prescribed, in determining the critical-engine-inoperative takeoff performance, takeoff flight path, and accelerate-stop distance, changes in the airplane's configuration, speed, and power must be made in accordance with procedures established by the applicant for operation in service.
(5) The procedures established under paragraphs (h)(3) and (h)(4) of this section must -
(i) Be able to be consistently executed by a crew of average skill in atmospheric conditions reasonably expected to be encountered in service;
(ii) Use methods or devices that are safe and reliable; and
(iii) Include allowance for any reasonably expected time delays in the execution of the procedures.