Abstract: Tractor (1) with driver's cab (2) at the rear, featuring a recess (3) in the front part of which the front steering wheels (4) of the aircraft are entering and are blocked by idle front rollers (28) which may be moved inwards or outwards and an idle rear roller (36) driven by hydraulic fluid powered pistons (31, 34). According to one solution, an apron (32) is mounted on the tractor framework (1) on which apron (32) the wheels (4) of the aircraft will rest. This apron is lifted and lowered by hydraulic fluid powered pistons (7) connected to the articulated upper arm (9) of each tractor wheel (6).

Abstract: An accident preventing arrangement for rotary snowplows includes a front safety bar in front of the rotating blades. When lowered, the safety bar actuates switches which, in turn, not only disengage a clutch for a drive shaft which rotates the blades, but also instantaneously brakes the blades. Another switch located in a driver's cab performs the same functions by manual operator control.