Bends and Corners

Cornering is the term used to describe the driving of a vehicle around a corner or bend. It is an important feature of driving and a thorough understanding of the theory is essential if a safe technique is to be mastered. The manner of approaching and negotiating the various bends and corners encountered in day to day motoring will vary according to the conditions prevailing at each, but the following general principles must be complied with at all times to ensure maximum safety:

Principles

  • Correct positioning of the vehicle on the approach side.
  • Right choice of speed
  • Correct gear for the speed
  • The vehicle to maintain a constant speed when negotiating the curve

Safety Factor

By the application of these principles, the following safety factors will be apparent as the machine is about to leave the bend or corner;

  • It will be on the correct side of the road
  • It will be able to remain there
  • It will be capable of being stopped in the distance the drive / rider can see to be clear

SLOW IN – FAST OUT

Roadworthiness of vehicles

A key element is the roadworthiness of your vehicle, in particular the vehicle load, conditions of tyres, tyre pressure and suspension. The road handling capability will also vary with the manufactures design specifications and characteristics of the vehicle itself.


Cornering Forces

When a vehicle is negotiating a corner certain forces are set up that will affect its road handling capabilities and unless the tyres retain sufficient grip on the road surface the driver will be unable to maintain the selected course.

Cornering Forces

M = The motion of the vehicle, which is proportionate to its Mass and Velocity
C = Is the centrifugal force applied to the vehicle whilst negotiating the corner or bend
R = Is resultant force and is the combination of both M and C

Where the resultant force exceed the motion and the centrifugal forces and where the coefficient of friction between the tyres and the road surface is reduced, the vehicle will go into a critical curve situation and will skid.

Tyre forces


Positioning and Vision

When approaching any bend the driver must position their vehicle to maintain the best view. From the information obtained their position may be adjusted to ensure the maximum margin of safety and maintain maximum stability as they negotiate the bend within the limits of their own half of the road.

Depending whether on a left or right hand bend the position must allow for a greater line of sight into the bend and any potential hazard at an early stage. Also by applying a larger circumference to the desired course the driver will achieve a greater degree of stability for the vehicle and will enhance their vision.

Remember ~ SLOW IN – FAST OUT

 

Stewart Rivers Chief Observer NET RoADA

Stewart Rivers is a Superintendent with the Metropolitan Police and their most senior practicing Class 1 driver

http://www.netroada.org