Pre-Trip Defects at 6:05 a.m.
At 6:05 a.m., you begin the pre-trip inspection of a 54-passenger school bus assigned to a 6:45 a.m. run with 38 students. Overnight temperature was 28°F. You find: (1) the left rear amber turn signal lens is cracked but the lamp flashes; (2) the stop arm extends only about 80% and sticks before fully deploying; (3) the driver-side red loading light does not illuminate, though the passenger-side red light works; (4) the air pressure builds from 85 to 100 psi in 50 seconds; (5) the rear tire on the right side has 4/32-inch tread on a dual tire. The dispatcher says the spare bus is blocked by a delivery truck and will not be free for 25 minutes. The route has 14 stops and a railroad crossing.
1. Which defects make the bus out of service, and what do you do?
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The stop arm that sticks at 80% and the inoperative driver-side red loading light are safety-critical loading/unloading defects. The bus cannot transport students until they are repaired because the stop arm may not command traffic and the red light system is incomplete. The cracked lens with a working lamp is a reportable minor defect. The 4/32-inch rear dual tread is at or near the minimum and needs immediate evaluation. The 85-to-100 psi build in 50 seconds is slower than the usual 45-second target and suggests an air problem; have a mechanic check it before dispatch. Complete a written defect report, notify dispatch, and request the spare or a delay. Do not sign off the bus as roadworthy.
2. The dispatcher tells you to take the bus because the spare will not be free and the route is short. How do you respond, and what documentation do you prepare?
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Refuse to transport students with the stop arm and red light defects. The dispatcher's schedule problem does not transfer the safety responsibility away from you as the driver. State the specific defects, ask for the spare or a mechanic, and document the refusal and the dispatcher's instruction in the defect report and dispatch log. If no replacement is available, the route waits. Once repaired, inspect the repaired items yourself before accepting the bus. The documentation should include the time, defect, who was notified, and the final disposition.
3. If the stop arm fails in service at the third stop, what should you do?
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Do not continue the route as if the bus is normal. Pull to a safe location, keep students aboard, and notify dispatch. If the red lights still work, use them and control the stop manually only if it is safe; but with a failed stop arm, the bus should be replaced or repaired before more students are loaded or unloaded. Complete an incident report. If the failure occurs while students are outside, keep them in a safe group away from traffic until the bus is secured or another bus arrives.