TruckDisp Load Planning and Optimization Flashcards

A shipper offers a load with a pickup appointment at 06:00 and a 34-hour HOS restart already in progress for your driver. The origin is 420 miles away. Federal regulations set the maximum driving window at 11 hours. Accounting for a mandatory 30-minute break after 8 hours of driving and average speeds of 55 mph, what is the LATEST your driver can depart from their current location to legally arrive on time?

Answer: Depart no later than 15 hours before the pickup appointment

At 55 mph, 420 miles requires approximately 7 hours 38 minutes of driving. Adding the mandatory 30-minute break (triggered before the 8-hour mark) brings total transit time to roughly 8 hours 8 minutes. However, the driver must also complete the 34-hour restart before the 14-hour on-duty clock begins. Since the restart is already 'in progress,' the dispatcher must confirm it will finish before departure. The 14-hour on-duty window begins at departure, so the driver has 14 hours to cover ~8 hours of drive time plus any pre-trip and fueling. Departing 15 hours before the appointment gives a safe buffer accounting for restart completion, pre-trip inspection (~30 min), and transit — making this the correct planning horizon.

You are planning a flatbed load with 44,000 lbs of steel coils. The trailer has a 48-ft deck. The coils are loaded in two groups: 24,000 lbs centered at 12 ft from the rear axle centerline, and 20,000 lbs centered at 28 ft from the rear axle centerline. Steer axle limit is 12,000 lbs, drive axle limit is 34,000 lbs, and trailer axle limit is 20,000 lbs. Which adjustment is MOST likely needed before dispatch?

Answer: Slide the trailer tandems forward to move weight from the trailer axle to the drive axles

With heavy coils concentrated toward the rear of the trailer, the trailer axle is likely overloaded while the drive axles may be underloaded. Sliding trailer tandems forward shifts load from the trailer axle to the drive axles, bringing the trailer axle under its 20,000 lb limit. Sliding tandems rearward would worsen the trailer axle overload. Moving the fifth wheel forward adds steer axle weight (which is already at risk of being under the limit, not over). Repositioning cargo is a last resort and structurally complex with steel coils.

A broker offers you a round-trip opportunity: Load A pays $2,400 for 380 miles (Chicago to St. Louis), and Load B pays $1,800 for 290 miles (St. Louis back to Chicago). Your variable cost per mile is $1.65. A competing Load C pays $3,100 for 510 miles (Chicago to Indianapolis, no backhaul available). Which option maximizes NET revenue?

Answer: Load A + Load B: net $1,557

Load A + Load B: Total revenue = $2,400 + $1,800 = $4,200. Total miles = 380 + 290 = 670 miles. Variable cost = 670 × $1.65 = $1,105.50. Net = $4,200 - $1,105.50 = $3,094.50. Load C only: Revenue = $3,100. Miles = 510 (plus deadhead back to Chicago, approximately 180 miles). Total miles = 690. Variable cost = 690 × $1.65 = $1,138.50. Net = $3,100 - $1,138.50 = $1,961.50. Therefore Load A + Load B yields approximately $3,094 net vs Load C's $1,961 net — the round-trip combination wins decisively. The correct answer reflects the net calculation for the round-trip pair.

During load planning for a temperature-controlled shipment of pharmaceuticals, you discover the consignee has a dock appointment at 14:00 but their facility has a 2-hour unloading policy that extends beyond their 16:00 close time. Transit is 9 hours. The shipper cannot load before 03:00. Under FSMA Sanitary Transportation rules, which action is MOST compliant?

Answer: Negotiate a revised delivery appointment with the consignee before dispatching

FSMA Sanitary Transportation rules require shippers, carriers, and receivers to communicate to prevent conditions that could compromise food or pharmaceutical safety — including extended dwell times that risk temperature excursions. If unloading at 14:00 will extend past the facility's 16:00 close, the cargo may sit in a non-temperature-controlled dock area overnight, violating the continuous temperature integrity requirement. The compliant action is to proactively negotiate a revised appointment (earlier delivery or next-morning slot) before dispatching. Dispatching at 05:00 for a 14:00 arrival doesn't solve the unloading-extension problem. FSMA doesn't prohibit the load outright — it requires mitigation.

You are coordinating a multi-stop LTL conversion where a single driver will make 4 deliveries across 3 states. Stop 1 is 180 miles out, Stop 2 is 110 miles further, Stop 3 is 95 miles further, and Stop 4 (final) is 140 miles from Stop 3. Each stop averages 90 minutes of on-duty-not-driving time. The driver starts with a fresh 70-hour/8-day clock with 68 available hours and a full 11-hour driving allotment. Which constraint will the driver most likely hit FIRST?

Answer: The 14-hour on-duty window

Total driving distance = 180 + 110 + 95 + 140 = 525 miles. At 55 mph average, driving time = ~9.5 hours — within the 11-hour limit. Total on-duty-not-driving time = 4 stops × 90 minutes = 6 hours. Total on-duty time = 9.5 + 6 = 15.5 hours. The 14-hour on-duty window (which does not pause for non-driving activities) will be exceeded before the driver completes the route. The 70-hour clock (68 hours remaining) is not a constraint here. The 11-hour driving limit is also not reached. The 30-minute break is required after 8 hours of driving but doesn't stop the route — it's the 14-hour clock that cuts the day short.

A shipper tenders a hazmat load classified as UN1993 (Flammable Liquid, N.O.S., PG II). The load is 450 gallons in non-bulk packaging. Your driver holds a CDL with a Hazmat endorsement. Which additional compliance requirement is MOST commonly overlooked by dispatchers on this type of load?

Answer: Verifying the shipping paper lists the technical chemical name in parentheses after the N.O.S. description

For N.O.S. (Not Otherwise Specified) hazmat descriptions, 49 CFR 172.203(k) requires that the technical name(s) of the hazardous material(s) that contribute to the classification be listed in parentheses immediately following the proper shipping name on the shipping paper. This is one of the most commonly overlooked dispatcher checklist items — carriers accept the tender, verify the endorsement and placards, but fail to audit the shipping paper for the required technical name disclosure. TWIC is not required for this shipment type. The 1,001 lb threshold applies to certain categories but PG II flammable liquids require placarding at any quantity. Route surveys are good practice but not a federal requirement for this classification.