# The Air Navigation (General) Regulations 1993, Regulation 8: Weight and performance of public transport aeroplanes classified as aeroplanes of performance group C in their certificates of airworthiness.


For the purposes of article 30(1), an aeroplane registered in the United Kingdom in respect of which there is in force under the Order a certificate of airworthiness in which the aeroplane is designated as being of performance group C shall not fly for the purpose of public transport unless the weight of the aeroplane at the commencement of the take off run is such that the following conditions are satisfied—
(1) That weight does not exceed the maximum take off weight specified for the altitude and the air temperature at the aerodrome at which the take off is to be made.
(2) The take off run required and the take off distance required, specified as being appropriate to—
(a) the weight of the aeroplane at the commencement of the take off run;
(b) the altitude at the aerodrome;
(c) the air temperature at the aerodrome;
(d) the average slope of the surface of the aerodrome in the direction of take off over the emergency distance available; and
(e) not more than 50 per cent. of the reported wind component opposite to the direction of take off or not less than 150 per cent. of the reported wind component in the direction of take off, do not exceed the take off run available and the emergency distance available, respectively, at the aerodrome at which the take off is to be made.
(3) (a) Subject to condition (4), the net take off flight path with all power units operating specified as being appropriate to—
(i) the weight of the aeroplane at the commencement of the take off run;
(ii) the altitude of the aerodrome;
(iii) the air temperature at the aerodrome; and
(iv) not more than 50 per cent. of the reported wind component opposite to the direction of the take off or not less than 150 per cent. of the reported wind component in the direction of take off;
and plotted from a point 50 feet above the end of the take off distance required at the aerodrome at which the take off is to be made to a height of 1,500 feet above the aerodrome shows that the aeroplane will clear any obstacle in its path by a vertical interval of not less than 35 feet; and if it is intended that the aeroplane shall change its direction of flight by more than 15° before reaching 1,500 feet the vertical interval shall be not less than 50 feet during the change of direction.
(b) For the purpose of sub-paragraph (a) an obstacle shall be deemed to be in the path of the aeroplane if the distance from the obstacle to the nearest point on the ground below the intended line of flight of the aeroplane does not exceed 75 metres.
(c) In assessing the ability of the aeroplane to satisfy this condition, it shall not be assumed to make a change of direction of a radius less than the specified radius of steady turn.
(4) (a) In the case of an aeroplane which is intended to be flown for any period before reaching a height of 1,500 feet above the aerodrome from which the take off is to be made in conditions which will not ensure that any obstacles can be located by means of visual observation, the net take off flight path with one power unit inoperative specified as being appropriate to the factors contained in sub-paragraphs (a)(i) to (iv) of condition (3), and plotted from the point of the net take off flight path with all power units operating specified as being appropriate to those factors at which in the meteorological conditions expected for the flight the loss of visual reference would occur, shows that the aeroplane will clear by a vertical interval of not less than 35 feet any obstacle in its path; and if it is intended that the aeroplane shall change its direction of flight by more than 15° before reaching 1,500 feet the vertical interval shall not be less than 50 feet during the change of direction.
(b) For the purpose of sub-paragraph (a) an obstacle shall be deemed to be in the path of the aeroplane if the distance from the obstacle to the nearest point on the ground below the intended line of flight of the aeroplane does not exceed—
(i) 75 metres plus one-eighth of the distance from such point to the end of the emergency distance available measured along the intended line of flight of the aeroplane; or
(ii) 900 metres,
whichever is the less.
(c) In assessing the ability of the aeroplane to satisfy this condition it shall not be assumed to make a change of direction of a radius of less than the specified radius of steady turn.
(5) The aeroplane at any time after it reaches a height of 1,500 feet above the aerodrome from which the take off is made will, in the meteorological conditions expected for the flight, in the event of any one power unit becoming inoperative at any point on its route or on any planned diversion therefrom, and with the other power unit or power units operating within the specified maximum continuous power conditions, be capable of continuing the flight at altitudes not less than the relevant minimum altitude for safe flight stated in, or calculated from the information contained in, the operations manual relating to the aeroplane to a point 1,500 feet above an aerodrome at which a safe landing can be made and after arrival at that point be capable of maintaining that height:
Provided that in assessing the ability of the aeroplane to satisfy this condition it shall not be assumed to be capable of flying at any point on its route at an altitude exceeding the performance ceiling, with all power units operating, specified as being appropriate to its estimated weight at that point.
(6) The landing weight of the aeroplane will not exceed the maximum landing weight specified for the altitude and the expected air temperature for the estimated time of landing at the aerodrome at which it is intended to land and at any alternate aerodrome.
(7) Subject to condition (8), the distance required by the aeroplane to land from a height of 50 feet otherwise than in accordance with specified data for short field landing does not, at the aerodrome at which it is intended to land and at any alternate aerodrome, exceed 70 per cent. of the landing distance available on the most suitable runway for a landing in still air conditions, and on the runway that may be required for landing because of the forecast wind conditions; and for the purposes of this condition the distance required to land from a height of 50 feet shall be taken to be that specified as being appropriate to—
(a) the landing weight;
(b) the altitude at the aerodrome;
(c) the temperature in the specified international standard atmosphere appropriate to the altitude at the aerodrome;
(d) (i) the level surface in the case of runways usable in both directions; or
(ii) the average slope of the runway in the case of runways usable in only one direction; and
(e) (i) still air conditions in the case of the most suitable runway for landing in still air conditions; and
(ii) not more than 50 per cent. of the forecast wind component opposite to the direction of landing or not less than 150 per cent. of the forecast wind component in the direction of landing in the case of the runway that may be required for landing because of the forecast wind conditions.
(8) As an alternative to condition (7), the distance required by the aeroplane, with all power units operating or with one power unit inoperative, to land in accordance with specified data for short field landing, does not at the aerodrome of intended destination and at any alternate aerodrome exceed the landing distance available on the most suitable runway for a landing in still air conditions and on the runway that may be required for landing because of the forecast wind conditions; and for the purposes of this condition the distance required to land from the appropriate height shall be taken to be that specified as being appropriate to the factors set forth in sub-paragraphs (a) to (e) of condition (7) and the appropriate height shall be—
(a) for a landing with all power units operating—any height between 30 and 50 feet in the United Kingdom, and 50 feet elsewhere; and
(b) for a landing with one power unit inoperative—50 feet in the United Kingdom and elsewhere:
Provided that—
(i) if the specified distance required to land with one power unit inoperative from a height of 50 feet at the aerodrome of intended destination exceeds the landing distance available, it shall be sufficient compliance with sub-paragraph (b) if an alternate aerodrome which has available the specified landing distance required to land with one power unit inoperative from such a height, is designated in the flight plan; and
(ii) the distance required by the aeroplane to land shall be determined in accordance with condition (7) and not in accordance with this condition if it is intended to land at night, or when the cloud ceiling or ground visibility forecast for the estimated time of landing at the aerodrome of intended destination and at any alternate aerodrome at which it is intended to land in accordance with specified data for short field landing with all power units operating, are less than 500 feet and one nautical mile respectively.

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Source: https://www.legislation.gov.uk/uksi/1993/1622/regulation/8 (the official version)
Page: https://openlegislation.uk/air-navigation-general-regulations-1993/regulation-8
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.