Why are aircraft pulled by Tow trucks before takeoff

Aircrafts are usually ‘pushed’ by ground vehicles known as tow vehicles or truck

To move an aircraft you need torque, lots of torque. A conventional car (even a Jeep) would be ultra underpowered to deliver so much amount of torque as needed to move a heavy jet. And that job is done by heavy vehicles having a high side wall ratio.

A bypass pin and a steering pin is inserted to the nose gear via an isolation valve to over ride the hydraulics of the aircraft giving the inputs to the actuators in the nose gear.

For starters, by employing this procedure, damage due to pilot error comes to a near zero, because pushback employed by tow drivers enables a 360-degree perception of field compared to the limited view the pilots have. This goes a long way in avoiding collisions at the airport. No collisions – no burning cash, no law suits .

Aircrafts don’t have powered wheels, and hence cannot move in reverse (let alone forward by themselves). Imagine a tiny jet strapped to one of your toy cars; that’s essentially how airplanes work on the ground! They go where the engines push them towards. (Note: There is a mechanism known as reverse thrusters, which allow the engine air flow to be pushed towards the front, but that is highly risky maneuver, and is only used to reduce speed immediately after landing.)

Another reason to push back an aircraft to a safe area, is for safety reasons. The engines produce tremendous thrust from the exit, and an immense vacuum from the front; enough to suck in people, small vehicles, ground equipment

Neither would companies buying the engines or the ones insuring engines against damages would be happy. Besides the increase in occupational hazards, the nuisance of debris entering the engines, wear-out, violation of noise regulations, jet blast damaging terminal buildings, a whole lot of factors why self propulsion is not recommended. Towing adds a further layer of value and increases employment opportunities. That is something desirable as well.

The aircrafts are pushed back only till the taxiway or that part of the apron where the aircraft can freely begin its forward movement, unrestricted by presence of people and light, freely movable equipment. That is when the engines start spooling up.

Virgin Atlantic did consider the prospect of pushing the aircrafts till the runway for saving fuel, but somehow the plan does not look like it has not been achieved