Driving and Operating Aerial Apparatus
Domain 4 covers moving the aerial: pre-trip brake checks, the handling characteristics that make these vehicles different, and the operating limits that apply on the road.
Vehicle characteristics
- High center of gravity and heavy wet weight - rollover risk in curves and on shoulders.
- Long wheelbase and rear overhang - off-tracking in turns, tail swing, and rearward amplification (the rear of the vehicle swings wider and faster than the front).
- Air brakes - full pre-trip test: static leakage, low-pressure warning, spring-brake pop-out, service brake, and parking brake.
- Height, length, and axle-weight limits: check overhead clearance and posted bridge limits before you commit.
Driving rules
- Following distance: at least 1 second per 10 ft of apparatus length, plus 1 second at speeds over 40 mph.
- Use a spotter for backing; if you have no spotter, get out and look.
- Due regard: warning devices do not exempt you from liability for reckless driving.
- Slow before the curve, not in it; brake smoothly and early to control weight transfer.
Worked example. A 45-ft quint traveling 50 mph: 45 ÷ 10 = 4.5 seconds, plus 1 second for speed over 40 mph = 5.5 seconds. At 50 mph (about 73 ft/s) that is roughly 400 ft of following distance - enough to stop an air-braked, heavy vehicle without locking the wheels.
Traps. Driving it like a car because it “has good brakes”; clipping a curb or hydrant with tail swing; forgetting the stowed height of the light bar and ladder; assuming the siren clears traffic; skipping the pre-trip air-brake test because the unit was driven yesterday.