A.V. Velikanov, E.V. Nosov

The complex work on aircraft flight readiness is being done by means of general application land maintenance, including its towage from a parking place to the technical positions for take off and landing preparation at the end of flight. The process of towage depending on distanced aircraft parking occupies from 15 to 25% of time needed for aircraft departure readiness. Existing means of towage can-t realize the big traction effort because of small coupling weight, especially on basic surfaces with low coupling factor. In this connection the use of a part of weight of the towed plane for creation of necessary traction effort on coupling with a basic surface is an actual problem. The perspective way of aircraft towage with the use of the twisting moment device supplied to the basic gear racks is offered. Traction characteristics design procedure of the towing system on various basic surfaces is specified and schedules are constructed. Fuel indicators of a all-wheel drive towing system are analyzed. Application of the offered device provides: the maximum draft force brought to a wheel, a coordination of transfer of a twisting moment to wheels of both racks of the plane at curvilinear movement, thanks to application of differential transfer, possibility increase because the towing system «tractor - aircraft» becomes all-wheel drive for towage. The research done allows to establish the use of the twisting moment device supplied to the basic gear racks, raises total traction characteristics of the all-wheel drive towing system on the all investigated basic surfaces, including a ground one. Fuel indicators of the all-wheel drive towing system are improved, since the considerable capacity growth of the all-wheel drive towing system reduces specific fuel consumption on 4%, despite increased (because of work of two power-plants) total fuel consumption per hour. Investigation of the all-wheel drive towing system operation in traction modes on various basic surfaces have shown that application of an active gear drive gives an effective growth of total traction effort of the tractor-aircraft unit. The active gear drive allows to use regular electrounits as tractors for aircraft towage on snow-covered, ice-covered and soil surfaces