Corners and Bends

When is a vehicle most stable?

• When it’s weight is evenly distributed

• When the engine is just pulling without increasing its road speed

• When it is travelling in a straight line on level ground

What are the three forces that affect the cornering stability of the vehicle?

• Braking

• Steering

• Acceleration

What other factors affect cornering?

• Slope of the road surface (camber)

• Characteristics of the vehicle

• Road surface and weather conditions

• Speed

Describe tyre-grip trade off

• The more grip used for acceleration or braking leaves less grip for steering

• If one or more of these forces (speed, road surface, slop, braking etc.) causes loss of tyre grip, vehicle will continue in a straight line rather than turning

Describe understeer and oversteer

• Understeer is tendency of vehicle to turn less to a given turn of the steering wheel

• Oversteer tendency of vehicle to turn more to a given turn of the steering wheel

What are the principles of cornering?

• Correct Position

• Correct Speed

• Correct Gear

• Correct Acceleration

• Be able to stop safely in distance you can see to be Clear

What are the benefits of following the principles of cornering?

• Increases patient comfort

• Increases vehicle sympathy

• Increases stability and view

• And therefore, increases safety. Never sacrifice safety for anything.

What sort off information can we gain on approach to a corner?

As much as possible, including:

• Weather

• Road surface

• Road signs and markings

• Line made by lamp posts and trees (forward vision for severity of bend)

• Speed and position of oncoming traffic

• Angle of headlights at night

• Limit point

Define limit point

Furthest point to which you have an uninterrupted view of the road surface

What position should we be in for a right hand bend and why?

What position should we be in for a left hand bend and why?

• P3 on right hand side of the road

• Provides View (as can see further around corner)

• Provides Stability (as less sharp corner)

• Does not provide safety, as closer to other road users

• If safety compromised for whatever reason (e.g. oncoming vehicles), move to P2 and don’t move back out