OSI 7717 International Standard INTERNATIONAL ORGANIZATION FOR STANDARDIZATION MEKAYHAPOAHAA OPIAHV3AUMH HO CTAHAAPTW3ALMW-ORGANISATION INTERNATIONALE DE NORMALISATION Aircraft -- Four-wheel-drive tow tractors - Performance requirements factors for design Aeronefs -- Tracteurs d'aeronefs a quatre roues motrices -- Parametres de conception First edition -- 1985-03-15 UDC 629.114.2 : 629.7 Ref. No. ISO 7717-1985 (E) (SO 7717-1985 (E) Descriptors : aircraft, towing attachments, tractors, performance evaluation, design. Price based on 5 pages Copyright International Organization for Standardization hitted without licensefrom IHS Not for Resale Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (IsO member bodies). The work of preparing International Standards is normally carried out through 1sO technical committees. Each member the right to be represented on that committee. International organizations, govern- mental and non-governmental, in liaison with ISO, also take part in the work. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by least 75 % approval by the member bodies voting. International Standard ISO 7717 was prepared by Technical Committee ISO/TC 20, Aircraft and space vehicles. International Organization for Standardization, 1985 Printed in Switzerland No reproduction or networking permitted without license from IHS Not for Resale ISO 7717-1985 (E) INTERNATIONAL STANDARD Aircraft -- Four-wheel-drive tow tractors - Performance requirements factors for design 1 Scope and field of application j) strength of the aircraft tow fitting when loads are applied This International Standard identifies and summarizes the 1) directly fore and aft, various factors that shall be considered and evaluated by the design or specifying engineer in establishing performance re- 2) in the direction of minimum strength; quirements for four-wheel-drive aircraft tow tractors. k) amount of thrust of engines at idle. The International Standard provides a summary of design fac- tors that shall be considered in establishing performance re quirements, as well as various tabulated design data and ex- 2.2 Airport environment planatory examples. The parameters to be taken into account are the following : It is not within the scope of this International Standard to specify a comprehensive set of design criteria for aircraft trac a) maximum grades to be negotiated; tors, but only those relating to performance requirements b) minimum speeds required for crossing active taxiways and runways; Design factors c) parking requirements : 1) parallel or nose-in at gates, The foliowing design factors shall be considered and evaluated in establishing aircraft tow tractor performance requirements. 2) spacing from other aircraft 3) proximity to other fixed physical features, 2.1 Aircraft characteristics 4) need for remote parking; : The parameters to be taken into account are the following : d) paving strength and surfacing of ramps, taxiways, run ways and access roads ; a) dimensions; e) road clearance and bridge and overpass limitations; b) number of landing gear and wheels; f) anticipated towing distances and routes between air- c) attach point for towing; craft maintenance/storage areas and cargo/passenger ter- minals ; d) gross weight, empty weight, and weight distribution on the wheels; maximum approach and breakover angles to be negotiated on ramps, taxiways, runways and access roads ; e) breakaway resistance of the aircraft as a percentage of aircraft weight for initial motion directed h) other towing equipment limitations, physical or 1) straight ahead, regulatory, unique to the local situation. 2) in a turn; f) rolling resistance of the aircraft as a percentage of air- 2.3 Tow vehicle - General characteristics craft weight for constant motion on various surfaces