General Knowledge: Aggressive Driving
5 questions in the bank cover this topic. Everything below is drawn from the sources those questions cite.
Sources: TC 21-305-20 para C-3, TC 21-305-20 para C-4, TC 21-305-20 para C-6
What you need to know
Aggressive driving in a high vehicle ends in a rollover rather than a skid.
The manual puts it plainly: speed kills, and overestimating what you and the vehicle can do is how it happens.
If the operator overestimates their abilities and that of their vehicle this could lead to a vehicle roll over.
TC 21-305-20 para C-3
Two things together: a sharp steering input and a load sitting high.
Either alone is survivable, but a high center of gravity means a smaller sideways force is enough to lift the inside wheels, and over-steering supplies it.
Over steering coupled with a high center-of-gravity may push the balance over the point by which vehicle remains stable (4 tires on the ground).
TC 21-305-20 para C-3
Heavy low, light high.
The manual names a high payload center of gravity as a major contributing factor to rollovers, and overloading or stacking heavy items up top is how a driver creates one. Loading them high raises the center of gravity.
If the crew overloads the vehicle or does not load the heavier items on bottom, the center-of-gravity will be raised higher.
TC 21-305-20 para C-6
An off-sided load is not just a weight distribution problem.
The manual lists handling, wear, sluggish control and side-to-side drift, so the driver feels it constantly and the vehicle degrades faster. All four follow from the same underlying fault.
If the load is off-sided the vehicle handling will be adversely affected. This will not only prematurely wear on the vehicle components but will also tend to make the vehicle sluggish to control or drift from side to side.
TC 21-305-20 para C-6
All four are edge-of-road hazards.
A steep shoulder or an abrupt drop-off turns a small lapse in lane position into a rollover, because one side of the vehicle falls away before the driver can correct. Water running alongside the road is the one drivers overlook.
Such terrain conditions that my contribute to a roll over are deeply rutted roadway, steep road shoulders, abrupt drop offs along roadway, canals or other bodies of water that parallel the roadway
TC 21-305-20 para C-4
Check yourself
- What is the result of overestimating your own and your vehicle's ability?
- What combination pushes a vehicle past the point where it stays stable?
- How should heavier items be placed in your load, and why?
- What four effects follow from a load that sits to one side?
- Which terrain conditions are named as contributing to rollovers?
Answers are in the practice test for this topic.