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(a) This Subpart prescribes aeroplane performance operating limitations applicable to—
(1) aeroplanes used in air operations; and
(2) aeroplanes, used in operations performed under Part 125 or Part 135, certificated to FAR Part 25 airworthiness standards, or equivalent airworthiness standards, that are—
(i) propeller-powered aeroplanes with a seating configuration of 20 seats or more; or
(ii) multi-engine turbojet or turbofan powered aeroplanes.
(b) Aeroplanes that cannot fully comply with the requirements of this Subpart may be approved to operate under alternative performance operating limitations.
Each holder of an air operator certificate must ensure that, for each aeroplane it operates—
(1) the take-off weight at the start of its take-off is not greater than the weight permitted under this Subpart for the flight to be undertaken allowing for—
(i) expected reductions in weight as the flight proceeds; and
(ii) such fuel jettisoning as is provided for under this Subpart; and
(2) the performance data used to determine compliance with the performance requirements of this Subpart is—
(i) contained in the aeroplane flight manual; or
(ii) in the case of contaminated runway landing distance data, provided by the aeroplane manufacturer and acceptable to the Director.
(a) Each holder of an air operator certificate must ensure that, for each aeroplane it operates, the take-off weight does not exceed the maximum takeoff weight specified in the aeroplane flight manual.
(b) When calculating the maximum take-off weight to determine compliance with paragraph (a), the certificate holder must, assuming that the critical engine fails at VEF and using a single V1, ensure that—
(1) the accelerate-stop distance required does not exceed the accelerate-stop distance available; and
(2) the take-off distance required does not exceed the take-off distance available; and
(3) any clearway forming part of the take-off distance available does not exceed half the length of the take-off run available; and
(4) in the case of a wet or contaminated runway, the take-off distance is calculated to the point at which the aircraft reaches a height of 15 feet above the take-off surface using a reduced V1; and
(5) the take-off run required does not exceed the take-off run available using V1 for the rejected and continued take-off; and
(6) on a wet or contaminated runway, the take-off weight does not exceed that permitted for a take-off on a dry runway under the same conditions.
(c) When calculating the maximum take-off weight in accordance with paragraph (b), the certificate holder must take account of—
(1) aerodrome elevation; and
(2) the pressure altitude of the aerodrome when the atmospheric pressure varies by more than 1% from the International Standard Atmosphere; and
(3) ambient temperature at the aerodrome; and
(4) the type of runway surface and the runway surface condition; and
(5) the runway slope in the direction of take-off; and
(6) not more than 50% of the reported headwind component or not less than 150% of the reported tailwind component.
Each holder of an air operator certificate must ensure that, unless performance data is available, the take-off distance calculated for a runway surface type under rule 121.207(c)(4) and the landing distance calculated under rule 121.221(c)(3), are corrected for use of other runway surface types by applying the factors in Table 1.
Table 1
| Surface Type | Take-off Distance Factor | Accelerate Stop Distance Factor | Landing Distance Factor |
|---|---|---|---|
| Paved | x 1.00 | x 1.00 | x 1.00 |
| Coral | x 1.00 | x 1.03 | x 1.05 |
| Metal | x 1.05 | x 1.06 | x 1.08 |
| Rolled earth | x 1.08 | x 1.14 | x 1.16 |
| Grass | x 1.14 | x 1.20 | x 1.18 |
(a) Each holder of an air operator certificate must ensure that, for each aeroplane it operates, assuming the critical engine is inoperative, all obstacles within the net take-off flight path are cleared vertically by at least—
(1) 35 feet in the case of a take-off performed by an aeroplane that is intended to use a bank angle not exceeding 15°; and
(2) 15 feet in the case of a take-off that is—
(i) performed by an aeroplane that is intended to use a bank angle not exceeding 15°; and
(ii) conducted in compliance with rule 121.207(b)(4); and
(3) 50 feet in the case of a take-off performed by an aeroplane that is intended to use a bank angle exceeding 15°; and
(4) 30 feet in the case of a take-off that is—
(i) performed by an aeroplane that is intended to use a bank angle exceeding 15°; and
(ii) conducted in compliance with rule 121.207(b)(4).
(b) For the purpose of paragraph (a), an obstacle is deemed to be within the net take-off flight path if the lateral distance from the obstacle to the intended line of flight does not exceed—
(1) where the intended flight path does not require a track change exceeding 15°—
(i) 75 m plus 0.125D, to a maximum of 600 m or, if the certificate holder has established visual or radio navigation track guidance procedures for the pilot, to a maximum of 300 m; or
(ii) for day operations in VMC by aeroplanes not exceeding 22 700 kg MCTOW, 45 m plus 0.125D, to a maximum of 600 m or, if the certificate holder has established visual or radio navigation track guidance procedures for the pilot, to a maximum of 300 m; or
(2) where the intended flight path requires a track change exceeding 15°—
(i) 75 m plus 0.125D, to a maximum of 900 m or, if the certificate holder has established visual or radio navigation track guidance procedures for the pilot, to a maximum of 600 m;
(ii) for day operations in VMC by aeroplanes not exceeding 22 700 kg MCTOW, 45 m plus 0.125D, to a maximum of 900 m or, if the certificate holder has established visual or radio navigation track guidance procedures for the pilot, to a maximum of 600 m.
(c) For the purpose of paragraph (b), D is the horizontal distance the aeroplane will travel from the end of the take-off distance available.
(d) When calculating the net take-off flight path in accordance with paragraph (a), the certificate holder must ensure that—
(1) the following factors are taken into account—
(i) take-off weight at the commencement of the take-off run; and
(ii) aerodrome elevation; and
(iii) pressure altitude at the aerodrome when the atmospheric pressure varies by more than 1% from the International Standard Atmosphere; and
(iv) ambient temperature at the aerodrome; and
(v) not more than 50% of the reported head-wind component or not less than 150% of the reported tail-wind component; and
(2) a track change exceeding 15° is not made before a height of 50 feet above the take-off surface has been achieved; and
(3) unless otherwise authorised by the Director—
(i) a bank angle exceeding 15° is not made before a height of 50 feet above the take-off surface has been achieved; and
(ii) the bank angle up to and including a height of 400 feet above the take-off surface does not exceed 20°; and
(iii) the bank angle above a height of 400 feet above the take-off surface does not exceed 25°; and
(4) allowance is made for—
(i) the effect of the bank angle on operating speeds and flight path; and
(ii) distance increments resulting from increased operating speeds; and
(iii) retention of stall margin and loss of climb gradient in accordance with rule 121.213.
(e) The certificate holder must establish contingency procedures to—
(1) satisfy the requirements of this Part; and
(2) provide a safe route avoiding obstacles; and
(3) enable the aeroplane to land safely at the aerodrome of departure, or at an alternate aerodrome required by rule 121.161.
Each holder of an air operator certificate must, unless performance data is available, for compliance with rule 121.211(d)(4)(iii), retain stall margin and calculate loss of climb gradient by applying the factors in Table 2.
Table 2
| Bank angle | Speed correction | Gradient correction |
|---|---|---|
| 15° to 19° | V2 | 1 x Aeroplane flight manual 15° gradient loss |
| 20° to 24° | V2 + 5 knots | 2 x Aeroplane flight manual 15° gradient loss |
| 25° | V2 + 19 knots | 3 x Aeroplane flight manual 15° gradient loss |
(a) Each holder of an air operator certificate must ensure that, for each aeroplane it operates, using the one engine inoperative en-route net flight path data—
(1) the flight path has a positive slope at an altitude of at least 1000 feet above all terrain and obstructions within, except as otherwise provided in paragraph (b), 10 NM of the intended track to be flown and at 1500 feet above the aerodrome where the landing is assumed to be made after engine failure; and
(2) the net flight path clears all terrain and obstructions within, except as otherwise provided in paragraph (b), 10 NM of the intended track by at least 2000 feet vertically; and
(3) the net flight path permits the aeroplane to continue flight from the cruising altitude to an aerodrome where a landing can be made in accordance with rule 121.221 or rule 121.223 as appropriate, taking account of—
(i) engine failure at the most critical point along the route; and
(ii) the effect of the icing protection systems if the meteorological conditions require their operation; and
(iii) the forecast ambient temperature; and
(iv) the effects of forecast wind on the flight path; and
(v) fuel jettisoning to an extent consistent with reaching the aerodrome with the required fuel reserves; and
(4) the aerodrome where the aeroplane is assumed to land after engine failure meets the following criteria—
(i) the performance requirements at the expected landing weight are met; and
(ii) weather reports and forecasts, or any combination thereof, and aerodrome condition reports indicate that a safe landing can be accomplished at the time of the intended landing.
(b) If the pilot is able, by the use of radio navigation aids, to maintain the intended track by a margin of 5 NM the distance of 10 NM required by paragraphs (a)(1) and (2) may be reduced to 5 NM.
(a) Except as provided in paragraph (b), each holder of an air operator certificate must ensure that each aeroplane it operates with three or more engines is not more than 90 minutes away from an aerodrome at which the performance requirements specified in the aeroplane flight manual applicable at the expected landing weight are met.
(b) The certificate holder may operate an aircraft with three or more engines more than 90 minutes away from an aerodrome at which the performance requirements specified in the aeroplane flight manual applicable at the expected landing weight are met, provided that—
(1) the two engine inoperative en-route flight path data permits the aeroplane to continue the flight, in the expected meteorological conditions, from the point where two engines are assumed to fail simultaneously, to an aerodrome at which it is possible to land using the prescribed procedure for a landing with two engines inoperative; and
(2) the net flight path, taking into account the effect of icing protection systems if the meteorological conditions require their operation has a positive slope clearing at an altitude of at least 2000 feet above all terrain and obstructions within, except as provided in paragraph (c), 10 NM of the intended track to be flown; and
(3) the net flight path has a positive slope at an altitude of 1500 feet above the aerodrome where the landing is assumed to be made after the failure of two engines; and
(4) the expected weight of the aeroplane at the point where the two engines are assumed to fail is not less than that which would include sufficient fuel to proceed to an aerodrome where the landing is assumed to be made, and to arrive there at an altitude of at least 1500 feet directly over the aerodrome and thereafter to fly level for at least 15 minutes.
(c) If the pilot is able, by the use of radio navigation aids, to maintain the intended track by a margin of 5 NM the distance of 10 NM required by paragraph (b)(2) may be reduced to 5 NM.
(d) When calculating compliance with paragraph (b), the certificate holder must assume the two engines fail at the most critical point of that portion of the route where the aeroplane is more than 90 minutes, at the all-engines long-range cruising speed at standard temperature and still air, away from an aerodrome at which the performance requirements applicable at the calculated landing weight are met.
Each holder of an air operator certificate must ensure that, for each aeroplane it operates—
(1) the landing weight of the aeroplane does not exceed the maximum approach and landing-climb weight, taking into account the altitude and the ambient temperature expected for the estimated time of landing at a destination and alternate aerodrome; and
(2) for instrument approaches with decision heights below 200 feet, the approach weight of the aeroplane, taking into account the takeoff weight and the fuel expected to be consumed in flight, allows a missed approach net-climb-gradient assuming that the critical engine is inoperative in the approach configuration of—
(i) at least 2.5%; or
(ii) at least the net-climb gradient required to clear any obstacles in the missed approach flight path in accordance with rule 121.211.
(a) A holder of an air operator certificate must ensure that, for each aeroplane it operates, the landing weight for the estimated time of landing will not exceed the landing weight specified in the aeroplane flight manual.
(b) A holder of an air operator certificate must, calculate the landing distance for an aeroplane on a runway using either –
(1) procedures that have been approved under paragraph (c); or
(2) the procedures provided in Appendix D.
(c) The Director may approve an application by a holder of an air operator certificate for procedures referred to in paragraph (b)(1) if satisfied of the following matters —
(1) that the aeroplane proposed has performance data issued by the manufacturer that supports the procedures and is available for use by the pilot or flight crew members; and
(2) that the operator has reliable access to either –
(i) accurate reporting on runway conditions that is appropriate for the procedures to be used; or
(ii) data that enables the operator to identify equivalent conditions; and
(3) that the margin of error applied when calculating landing distance using the permitted procedures takes into account the following –
(i) the implications of pilot technique on landing distance;
(ii) the implications of unexpected environmental conditions at the destination aerodrome;
(iii) whether the calculation is being undertaken at the dispatch stage or en-route;
(iv) whether the margin of error is supported by the reporting of the runway conditions; and
(4) that all personnel involved in the reporting of runway conditions, calculation of data and operation of the flight have had appropriate training in the use of the procedures.
A holder of an air operator certificate may perform steep approach procedures using approach slope angles of 4.5°, or more, and with screen heights of less than 50 feet but not less than 35 feet, if—
(1) the aeroplane flight manual states the maximum authorised approach slope angle, any other limitations, procedures, including emergency procedures, for the steep approach, as well as amendments for the field length data when using steep approach criteria; and
(2) for air operations performed under IFR, an approach slope indicator system comprising at least a visual approach slope indicating system is available for the runway to be used at the aerodrome at which steep approach procedures are to be conducted; and
(3) for air operations performed under IFR, weather minima are specified and approved for each runway to be used with a steep approach; and
(4) for air operations performed under IFR, consideration is given to—
(i) obstacles; and
(ii) the type of approach slope indicator reference and runway guidance such as visual aids, MLS, GNSS, ILS, LOC, VOR, or NDB; and
(iii) the minimum visual reference to be required at DH and MDA; and
(iv) usable airborne equipment; and
(v) pilot qualification and special aerodrome familiarisation; and
(vi) aeroplane flight manual limitation and procedures; and
(vii) missed approach criteria.
