NC CDL Air Brakes case studies
NC CDL Air Brakes · Put your knowledge to work in context.
The NC CDL Air Brakes knowledge test is one of the written tests NCDMV administers to commercial driver license applicants in North Carolina. Federal law requires commercial drivers to pass the knowledge tests for the appropriate license, including assessments, to obtain a commercial learner permit, so air brakes knowledge is tested at the permit stage rather than at the road skills test. The test matters most for drivers who will operate air-brake-equipped commercial motor vehicles: NCDMV records a restriction if the vehicle used for skills testing is not air brake equipped. It is built around four areas: air brake system components and warning devices, inspection and pre-trip checks, operation and braking technique, and malfunctions and emergency procedures. The NC CDL Air Brakes case studies are 5 cases and about 2,883 words.
1Low Air Pressure on the Saluda Grade
Your 2019 tractor is pulling a 53-foot van loaded to 42,000 pounds down the 7% grade on I-26 near Saluda, North Carolina. You entered the grade at 45 mph in 8th gear with the engine brake on high.
646 words, about 3 min2Pre-Trip Leak Test After a Compressor Replacement
You are doing a pre-trip on a three-axle tractor with duals pulling a tandem-axle van. The combination was just serviced for a compressor replacement.
562 words, about 3 min3Six Percent Grade in the Rain
You are driving a 68,000-pound GCW tractor-trailer down a 6% grade that runs for four miles. The posted truck speed is 35 mph.
577 words, about 3 min4Secondary Gauge Falling at Idle
After a 30-minute drive, your truck sits idling in a delivery yard. The dual air gauges show 105 psi on the primary (rear brake) system and 88 psi on the secondary (front brake) system.
561 words, about 3 min5Severed Trailer Emergency Line at Night
You are driving a 38,000-pound loaded trailer at 45 mph on a two-lane road at night. Without warning you hear a loud bang from the trailer, the trailer air supply knob pops out, and the trailer brakes lock.
537 words, about 3 min