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Difficulty: HardSkidding Causes and Prevention

Applying firm footbrake pressure during a rear-wheel skid (oversteer) increases vehicle stability by transferring dynamic weight onto the rear tyres to enhance their grip.

Answer: Answer

Answer

False. Applying the footbrake unloads the rear axle through forward dynamic weight transfer, which decreases rear tyre traction and severely worsens an oversteer skid.
The statement is false because applying the footbrake initiates forward dynamic weight transfer, which relieves pressure from the rear wheels and reduces their available grip. Demanding longitudinal braking force from tyres that are already sliding laterally overloads their friction limit and worsens the skid.

Step-by-Step Solution

1
Analyse the effect of braking on dynamic vehicle weight distribution.
Braking decelerates the vehicle, causing forward pitch and transferring vertical load from the rear axle to the front axle.
Inertial forces shift the centre of dynamic mass forward during deceleration.
2
Evaluate the impact of axle unloading on tyre adhesion limits.
The rear tyres experience a substantial decrease in normal force (contact pressure), reducing their maximum available lateral grip.
Tyre friction limit is directly proportional to the vertical load acting on the contact patch.
3
Determine vehicle yaw behavior during the skid.
The unweighted rear tyres lose remaining lateral grip, causing the rear of the car to swing out further into a violent spin.
Adding braking torque consumes traction on tyres that have already exceeded their lateral grip threshold.

Key Concept

Dynamic weight transfer and tyre adhesion limits during oversteer skid recovery
Estimated Time:1m 0s
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Topics

Skidding Causes and Prevention

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