Multi-engine aeroplanes powered by:
¾ Turbopropeller engines with a maximum approved passenger seating configuration of more than 9 or a maximum take-off mass exceeding 5700 kg, and
¾ All multi-engine turbojet powered aeroplanes
are operated in accordance with JAR-OPS, Subpart G – Performance Class A JAR-OPS 1.485 – General
The operator ensures the approved performance data in the Aeroplane Flight Manual is supplemented as necessary with other data acceptable to the Authority if the Approved Performance Data in the Aeroplane Flight Manual is insufficient with respect to items such as:
¾ Accounting for reasonably expected adverse operating conditions such as take- off and landing on contaminated runways, and
¾ Consideration of engine failure in all flight phases.
An operator shall ensure that, for the wet and contaminated runway case, performance data determined in accordance with JAR 25X1591 or equivalent acceptable to the Authority is used.
General - Wet and Contaminated Runway Data (JAR – 25 AMJ 25X1591)
If the performance data has been determined on the basis of measured runway friction coefficient, the operator should use a procedure correlating the measured runway friction coefficient and the effective braking coefficient of friction of the aeroplane type over the required speed range for the existing runway conditions.
Operation on Contaminated Runways
Operation on runways contaminated with water, slush, snow or ice implies uncertainties with regard to runway friction and contaminant drag. The achievable performance and control of the aeroplane during take-off may not match the calculated figures since the actual conditions may not completely match the assumptions on which the performance information is based. In the case of a contaminated runway, the first option for the commander is to wait until the runway is cleared. If this is impracticable, he may consider a take-off, provided that he has applied the applicable performance adjustments, and any further safety measures he considers justified under the prevailing conditions.
An adequate overall level of safety will only be maintained if operations in accordance with JAR-25 AMJ 25X1591 are limited to rare occasions. Where the frequency of such operations on contaminated runways is not limited to rare occasions, operators should provide additional measures ensuring an equivalent level of safety. Such measures should include special crew training, additional distance factoring and more restrictive wind limitations.
JAR-OPS 1.490 - Take-Off
The operator is to ensure that the take-off mass does not exceed the maximum take-off mass specified in the Aeroplane Flight Manual for the pressure altitude and the ambient temperature at the aerodrome at which the take-off is to be made.
The operator must meet the following requirements when determining the maximum permitted take-off mass:
¾ The accelerate-stop distance must not exceed the accelerate-stop distance available
¾ The take-off distance must not exceed the take-off distance available, where clearway is not more than 50% of TORA
¾ The take-off run must not exceed the take-off run available
¾ A single value of V1 for the rejected and continued take-off must be used, and
¾ On a wet or contaminated runway, the take-off mass must not exceed that permitted for a take-off on a dry runway under the same conditions.
The following must be taken into account:
¾ The pressure altitude at the aerodrome
¾ The ambient temperature at the aerodrome and
¾ The runway surface condition and the type of runway surface The runway slope in the direction of take-off
¾ Not more than 50% of the reported head-wind component or not less than 150% of the reported tailwind component, and
¾ The loss, if any, of runway length due to alignment of the aeroplane prior to take- off. This is discussed in Chapter 3)
JAR-OPS 1.495 - Take-Off Obstacle Clearance
The operator ensures that the net take-off flight path clears all obstacles by a vertical distance of at least:
¾ 35 ft, or
¾ By a horizontal distance of at least 90 m plus 0·125 x D, where D is the horizontal distance the aeroplane has traveled from the end of the take-off distance available or the end of the take-off distance if a turn is scheduled before the end of the take-off distance available.
Aeroplanes with a wingspan of less than 60 m a horizontal obstacle clearance of half the aeroplane wingspan plus 60 m, plus 0.125 x D may be used.
In accordance with the definitions used in preparing the take-off distance and take-off flight path Data provided in the Aeroplane Flight Manual:
The net take-off flight path is considered to begin at a height of 35 ft above the runway or clearway at the end of the take-off distance determined by the method shown below.
The take-off distance is greater of the following distances:
¾ 115% of the distance with all engines operating from the start of the take-off to the point at which the aeroplane is 35 ft above the runway or clearway, or
¾ The distance from the start of the take-off to the point at which the aeroplane is 35 ft above the runway or clearway assuming failure of the critical engine occurs at the point corresponding to the decision speed (V1) for a dry runway, or
¾ If the runway is wet or contaminated, the distance from the start of the take-off to the point at which the aeroplane is 15 ft above the runway or clearway assuming failure of the critical engine occurs at the point corresponding to the decision speed (V1) for a wet or contaminated runway.
JAR-OPS 1.495(a) specifies that the net take-off flight path, determined from the data provided in the Aeroplane Flight Manual must clear all relevant obstacles by a vertical distance of 35 ft.
When taking off on a wet or contaminated runway and an engine failure occurs at the point corresponding to the decision speed (V1) for a wet or contaminated runway may clear close-in
obstacles by only 15 ft. When taking off on wet or contaminated runways. The operator should exercise special care with respect to obstacle assessment, especially if a take-off is obstacle is limited and the obstacle density is high.
Account must be taken of the following:
¾ The mass of the aeroplane at the commencement of the take-off run, ¾ The pressure altitude at the aerodrome,
¾ The ambient temperature at the aerodrome, and
¾ Not more than 50% of the reported head wind component or not less than 150% of the reported tailwind component.
When showing compliance with the above:
¾ Track changes are not allowed up to the point at which the net take-off flight path has achieved a height equal to one half the wingspan but not less than 50 ft above the elevation of the end of the take-off run available. Up to a height of 400 ft it is assumed that the aeroplane uses no more than 15° AOB. Above 400 ft height bank angles greater than 15°, but not more than 25° may be used
¾ Any part of the net take-off flight path in which the aeroplane is banked by more than 15° must clear all obstacles by a vertical distance of at least 50 ft, and
¾ The operator must use special procedures, subject to the approval of the Authority, to apply increased bank angles of not more than 20° between 200 ft and 400 ft, or not more than 30° above 400 ft
¾ For the use of increased bank angles requiring special approval, the following criteria have to be met:
¾ The Aeroplane Flight Manual must contain approved data for the required increase of operating speed and data to allow the construction of the flight path considering the increased bank angles and speeds.
¾ Visual guidance must be available for navigation accuracy. ¾ Weather minima and wind limitations must be specified for each
runway and approved by the Authority.
¾ Adequate allowance must be made for the effect of bank angle on operating speeds and flight path including the distance increments resulting from increased operating speeds.
¾ The Aeroplane Flight Manual generally provides a climb gradient decrement for a 15° bank turn. For bank angles of less than 15°, a proportionate amount should be applied, unless the manufacturer or Aeroplane Flight Manual has provided other data.
¾ Unless otherwise specified in the Aeroplane Flight Manual or other performance or operating manuals from the manufacturer, acceptable adjustments to assure adequate stall margins and gradient corrections are provided by the following:
Bank
Angle Speed Gradient Correction
15° V2 Aeroplane Flight Manual 15° Gradient loss
20° V2 + 5 kt 2 x Aeroplane Flight Manual 15° Gradient
loss
25° V2 + 10 kt 2 x Aeroplane Flight Manual 15° Gradient
loss
Where the intended flight path does not require track changes of more than 15°, an operator need not consider those obstacles which have a lateral distance greater than:
¾ 300 m, if the pilot is able to maintain the required navigational accuracy through the obstacle accountability area, or
Where the intended flight path does require track changes of more than 15°, an operator need not consider those obstacles which have a lateral distance greater than:
¾ 600 m, if the pilot is able to maintain the required navigational accuracy through the obstacle accountability area, or
¾ 900 m for flights under all other conditions.
The operator establishes contingency procedures to satisfy the requirements of JAR-OPS 1.495 and to provide a safe route, avoiding obstacles, to enable the aeroplane to either comply with the en-route requirements of JAR-OPS 1.500, or land at either the aerodrome of departure or at a take-off alternate aerodrome.
If the above is based on an engine failure route that differs from the all engine departure route or SID normal departure, a "deviation point" can be identified where the engine failure route deviates from the normal departure route. Adequate obstacle clearance along the normal departure with failure of the critical engine at the deviation point will normally be available. In certain situations the obstacle clearance along the normal departure route may be marginal and should be checked to ensure that, in case of an engine failure after the deviation point, a flight can safely proceed along the normal departure.
JAR-OPS 1.500 - En-Route - One Engine Inoperative
The operator ensures that the one engine inoperative en-route net flight path data shown in the Aeroplane Flight Manual complies with parameters set out in the next two paragraphs below at all points along the route. The net flight path must have a positive gradient at 1500 ft above the aerodrome where the landing is assumed to be made after engine failure. In meteorological conditions requiring the operation of ice protection systems, the effect of their use on the net flight path must be taken into account.
¾ The gradient of the net flight path must be positive at least 1000 ft above all terrain and obstructions along the route within 9·3 km (5 nm) on either side of the intended track.
¾ The net flight path must permit the aeroplane to continue flight from the cruising altitude to an aerodrome where a landing can be. The net flight path clearing vertically, by at least 2000 ft, all terrain and obstructions along the route within 9.3 km (5 nm) on either side of the intended track with regard to the following:
¾ The engine is assumed to fail at the most critical point along the route, ¾ Account is taken of the effects of winds on the flight path,
¾ Fuel jettisoning is permitted to an extent consistent with reaching the aerodrome with the required fuel reserves, if a safe procedure is used, and
¾ The aerodrome where the aeroplane is assumed to land after engine failure must meet the following criteria:
¾ The performance requirements at the expected landing mass are met, and
¾ Weather reports or forecasts, or any combination thereof, and field condition reports indicate that a safe landing can be accomplished at the estimated time of landing.
The operator must increase the width margins above to 18·5 km (10 nm) if the navigational accuracy does not meet the 95% containment level.
JAR-OPS 1.505 - En-route - Aeroplanes with Three or More Engines, Two Engines Inoperative
At no point along the intended track will an aeroplane having three or more engines be more than 90 minutes, at the all-engines long range cruising, away from an aerodrome at which the performance requirements applicable at the expected landing mass are met unless it complies with the paragraphs below.
The two engines inoperative en-route net flight path data must permit 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 and come to a complete stop when using the prescribed procedure for a landing with two engines inoperative. The net flight path must clear vertically, by at least 2000 ft all terrain and obstructions along the route within 9·3 km (5 nm) on either side of the intended track. At altitudes and in meteorological conditions requiring ice protection systems to be operable, the effect of their use on the net flight path data must be taken into account. If the navigational accuracy does not meet the 95% containment level, an operator must increase the width margin given above to 18·5 km (10 nm).
The two engines are assumed to 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, away from an aerodrome at which the performance requirements applicable at the expected landing mass are met.
The net flight path must have a positive gradient at 1500 ft above the aerodrome where the landing is assumed to be made after the failure of two engines.
Fuel jettisoning is permitted to an extent consistent with reaching the aerodrome with the required fuel reserves, if a safe procedure is used.
The expected mass of the aeroplane at the point where the two engines are assumed to fail must not be less than that which would include sufficient fuel to proceed to:
¾ An aerodrome where the landing is assumed to be made, and ¾ To arrive there at least 1500 ft directly over the landing area, and ¾ To fly level for 15 minutes.
JAR-OPS 1.510 - Landing - Destination and Alternate Aerodromes
The landing mass of the aeroplane must not exceed the maximum landing mass specified for the altitude and the ambient temperature expected for the estimated time of landing at the destination and alternate aerodrome.
For instrument approaches with decision heights below 200 ft, an operator must verify that the approach mass of the aeroplane, taking into account the take-off mass and the fuel expected to be consumed in flight, allows a missed approach gradient of climb, with the critical engine failed and with the speed and configuration used for go-around of at least 2·5%, or the published gradient, whichever is the greater.
The Authority must approve the use of an alternative method
The missed approach procedure of an instrument approach as shown on instrument approach charts is normally based on an obstacle clearance surface having a slope of 2.5%. All aeroplanes cannot achieve this when operating at or near maximum certificated landing mass and in engine-out conditions. Operators of these aeroplanes should consider mass, altitude and temperature limitations and wind for the missed approach at aerodromes which are critical due to obstacles in the missed approach areas. An increase in the decision altitude/height or minimum descent altitude/height may, as a result, be required.
JAR-OPS 1.515 - Landing - Dry Runways
The landing mass of the for the estimated time of landing at the destination aerodrome and at any alternate aerodrome must be such as to allow a full stop landing from 50 ft above the threshold:
¾ For turbo-jet powered aeroplanes, within 60% of the landing distance available, or ¾ For turbo-propeller powered aeroplanes, within 70% of the landing distance
available,
¾ For Steep Approach procedures the Authority may approve the use of landing distance Data based on a screen height of less than 50 ft, but not less than 35 ft. ¾ The Authority may exceptionally approve, when satisfied that there is a need, the
use of Short Landing Operations
When showing compliance with the above, an operator must take account of the following: ¾ The altitude at the aerodrome,
¾ Not more than 50% of the head-wind component or not less than 150% of the tailwind component, and
¾ The runway slope in the direction of landing if greater than ± 2%. When showing compliance with sub-paragraph (a) above, it must be assumed that:
¾ The aeroplane will land on the most favourable runway, in still air, and
¾ The aeroplane will land on the runway most likely to be assigned considering the probable wind speed and direction and the ground handling characteristics of the aeroplane, and considering other conditions such as landing aids and terrain.
If an operator is unable to comply with the above for a destination aerodrome having a single runway where a landing depends upon a specified wind component, an aeroplane may be despatched if 2 alternate aerodromes are designated which permit compliance.
Before commencing an approach to land at the destination aerodrome the commander must satisfy himself that a landing can be made with regard to the above paragraphs.
Where the landing conditions at the destination mean that the above conditions cannot be complied with the operator may still despatch the aeroplane. This may be done if the conditions at the alternate are such that the rules for landing are complied with.
Steep Approach Procedures
The Authority may approve the application of Steep Approach procedures using glideslope angles of 4·5° or more and with screen heights of less than 50 ft but not less than 35 ft, provided that the following criteria are met:
¾ The Aeroplane Flight Manual must state the maximum approved glideslope angle, any other limitations, normal, abnormal or emergency procedures for the steep approach as well as amendments to the field length data when using steep approach criteria,
¾ A suitable glidepath reference system comprising at least a visual glidepath indicating system must be available at each aerodrome at which steep approach procedures are to be conducted, and
¾ Weather minima must be specified and approved for each runway to be used with a steep approach.
Consideration must be given to the following: ¾ The obstacle situation,
¾ The type of glidepath reference and runway guidance such as visual aids, MLS, 3D-NAV, ILS, LLZ, VOR, NDB,
¾ The minimum visual reference to be required at DH and MDA, ¾ Available airborne equipment,
¾ Pilot qualification and special aerodrome familiarisation, ¾ Aeroplane Flight Manual limitations and procedures, and
¾ Missed approach criteria.
JAR-OPS 1.520 - Landing - Wet and Contaminated Runways
When the appropriate weather reports or forecasts indicate that the runway at the estimated time of arrival may be wet or contaminated, the landing distance available must be at least 115% of the required landing distance.
A landing distance on a wet runway shorter than that required, but not less than that required