Turning A Semi-Truck & Trailer Correctly
Give Me 40 Acres and I’ll Turn This Rig Around
The 1964 trucking anthem “Give Me 40 Acres and I’ll Turn This Rig Around” by the Willis Brothers humorously captures the frustrations and challenges faced by new drivers behind the wheel of a big rig. One of the most daunting aspects of driving a big rig is turning a semi-truck and trailer correctly.
During road tests, it’s common for novice drivers to make the mistake of taking corners too sharply, often causing the trailer tires to ride up over the curb—leading to demerits and potential accidents.
While shifting gears may seem like the most immediate priority for new drivers, turning is arguably more critical to avoid collisions and prevent costly damage. Learning to navigate turns is not only essential for a successful road test but also for ensuring safety on the road.
In my time at the driving school in Vernon, British Columbia, Bill Walker earned himself a place as a model student. He completed the tractor-trailer training in 3-weeks. On the Thursday he passed his driver’s test, and the following Tuesday, he was working in the oil fields in Alberta, north of Fort McMurray.
After a few months of working, he contacted me at the driving school. He was proud of his accomplishment and wanted to take his Dad for a drive in the truck. The school agreed and Bill and I arranged a time and a place.
The three of us climbed into the truck. Bill’s Dad sat on the bed in the bunk. Bill was a big affable guy. As he sat in the driver’s seat, I could tell the drive was as much about impressing me, as it was showing his Dad his new skillset.
We started off, making our way north through town. Bill’s shifting had improved. He no longer used the clutch, and simply “floated the gears”. Going out of town and merging onto Highway 97 north, Bill’s turns were still a bit clunky.
Bill got off the highway and turned left onto Highway 97C toward Kamloops. The plan was to go around Swan Lake and head back into town.
Professional CDL trainers know that it takes a new driver six months to a year to turn a semi-truck and trailer correctly.
Making the left turn from Highway 97 onto Old Kamloops Road is tricky. At that intersection, the highway curves sharply to the right which impedes visibility of oncoming traffic. Three events happened that—in a different traffic situation—could have gone badly.
1) When Bill approached the intersection in the left turning lane, he failed to position the truck on the right side of the lane;
2) Bill misjudged the gap in oncoming traffic. He started, but realized there was another vehicle and slammed on the brakes to stop. Bill became flustered.
3) As Bill waited to turn, a car stopped at the northbound entrance of Old Kamloops Road and the highway. When Bill turned left, he failed to both drive deep enough into the intersection before turning and use the space in the slip lane to compensate for the trailer’s off-tracking.
Consequently, the trailer stuck out into highway traffic while the car reversed, allowing Bill to complete his turn.
It’s challenging imparting to new drivers the utter importance of turning owing to the fact that its relevance is eclipsed by their need and desire to master shifting a non-synchromesh transmission.
Shifting however, will most likely not cause a crash or collision resulting in damage or death.
Turning a semi-truck and trailer correctly, on the other hand, sometimes results in tragedy!
Rick August, PhD
Working as as Expert Witness, Dr. August provides testimony in crash analysis, traffic safety, road user behavior, and driver education. His expertise is in commercial vehicles (trucks & buses), duty of care, and air brakes.
The 5 Learning Components of a Semi-Truck & Trailer Course
There are 5 basic modules to a Class 1 (Class A or Tractor-Trailer) Driver Training curriculum.
These are as follows in order of importance for pass your driver’s license:
1) Turning
2) Pre-trip Inspection
3) Shifting
4) Backing
5) Unhook/Hook
The importance of the above five components will depend on your test centre.
Some test centres will only require you to back in a straight line, which is relatively simple.
Other test centres require that you parallel park or back around a corner, which is significantly more challenging.
As a driving instructor teaching people to drive semi-trucks and trailers, I often think that I should have a recording:
• “You’re not in the right gear driver! “What gear were you supposed to be in for that turn?”
• “Move right to turn left; move left to turn right.”
• “You have to “box” your corners more.”
• “Slow down in your turns – the slower you go, the sharper the vehicle turns.”
• “The trailer drives the truck; not the truck!”
• “When the trailer tires are halfway around the corner, your done the turn.”
• “The truck (towing unit) can go anywhere, so long as the trailer stays in the lane.”
• “Watch the mirrors—70/30—70% looking in the mirrors during a turn and 30% looking forward.
TURNING
Like backing, most of the work done for a turn is completed even before the turn occurs.
Set-up and positioning the vehicle before the turn is the most important component of a successful turn.
Seeing Intersections as a Different Space
As a truck driver, you must see the space in an intersection different than a car driver.
To successfully and safely turn a semi-truck around a corner, you will have to drive outside the tracks of other traffic.
In most cities, this means driving in the “gutter dirt” piled up next to traffic islands.
When turning left, a semi-truck driver must drive deep into the intersection and “box’ the turn to compensate for the trailer’s off-tracking and keep 53’ ft (16m) of semi-trailer in it’s lane.
Splay is how much the corners of the intersection are rounded. On major roads, the corners of the intersection are rounded a LOT to accommodate the movement and turning of large vehicles. Increased splay also increases visibility at the intersection. On many residential streets, the splay of the corner will not be rounded at all, but will be a 90° corner.
Questions to ask when approaching an intersection to make a right turn:
• Is it a major intersection or a minor intersection?
• How wide is the lane you’re in?
• Is there a slip lane (right-turning lane)?
• Is there a truck apron (an area of the road designed to accommodate the off-tracking of large vehicles)?
• If not, how big is the splay?
• Where are the utility poles and traffic signs at the intersection?
• Are there pedestrians, cyclists or other vulnerable road users at the intersection?
• Is there a left-turning lane on the cross-street?
Questions to ask when approaching an intersection to make a left turn:
• Is it a major intersection or a minor intersection?
• How big is the splay at the intersection?
• How wide is the lane you’re in?
• Is there a left-turning lane?
• Is there are right turning lane on the opposite side of the intersection?
• Is there a left-turning lane on the cross-street?
• Is there a traffic island in the center of the cross-street onto which you’re turning?
• Where are the utility poles and traffic signs on the above traffic island?
• Are there pedestrians, cyclists or other vulnerable road users at the intersection that may cross your path-of-travel?
• Is there a left-turning lane on the cross-street?
Defensive Turning in a Semi-Truck and Trailer
The harsh reality of driving a semi-truck and trailer is that the proverbial “4-wheeler” (car drivers) are oblivious of semi-trucks. Well…you know, almost all other traffic on the roadway for that matter.
In other words, they don’t care about trucks, don’t know about semi-trucks, and they just see you as in their way…if even they see you or take note of you at all.
Your job as a professional truck driver is to get in the way of other traffic as “LITTLE” as possible.
The first rule for turning a semi-truck defensively, is to take the space you need from the road onto which you’re turning, NOT from the road you’re on.
It takes 3 lanes to get a tractor-trailer around a corner.
Too many truck drivers will swing wide into the left lane of a multi-lane road to make a right turn.
First this turning tactic is unpredictable. If a maneuver is unpredictable in traffic, that means it’s dangerous. At some point therefore, this moving left out of your lane and exposing your “blind side” will lead to a crash.
As stated, car drivers have NO IDEA what you’re doing.
Second, and far more dangerous, is the fact that you put obstacles and obstructions on the blind side (the passenger side) of your rig.
By taking the space from the road onto which you’re turning, you keep hazards and obstructions and traffic in front and on the sight-side of your truck.
For example, if there’s a left turning lane on the cross-road onto which you’re turning, use that space to get the truck and trailer around the corner. If there’s traffic in the left turning lane, simply stop and wait for the traffic light. When the lane is clear, then proceed with your turn.
If you’re in the process of making your turn and a vehicle approaches the intersection. Most of the time, the driver will slow and allow you to complete your turn. If the other driver doesn’t slow, simply stop and wait.
As part of your setup to make the turn, you must get the transmission into the right gear to turn correctly.
In a truck equipped with an 18- or 13-speed transmission these general rules apply:
• “Rights & tights” – 3rd gear OR 15kph (9mph)
• Left-hand turns can often be done in 4th gear (20-25kph OR 12-15mph).
Big right-hand corners that have slip lanes (turning lanes) designed for bigger vehicles can often be done in 5th gear – (20-30kph OR 12-18mph).
The correct speed allows several things to happen:
• The slower the vehicle travels, the sharper it turns;
• If the driver is going slow, she has time to observe the trailer’s path through the corner;
Observation is key:
• 70% of observation through a corner must be the driver looking in the mirrors to track the trailer’s path of travel.
The driver has to move her head – forward, mirror, forward, shoulder checking, mirror….and so on.
If the driver is going slow and observing, and something happens during the turn—another road user moves into her path of travel, for example—she can get the unit stopped;
And finally, if the driver makes a mistake and strikes another road user or fixed object, she can minimize the damage because she’s going to get the unit stopped sooner.
When turning a commercial vehicle, a driver’s job is to minimize their impediment to other traffic.
In other words, if you have to take up additional lanes, the time in lanes of opposing traffic has to be minimal – take up the least amount of space for the least amount of time.
And if there is traffic in the space that you require for turning, you must stop and wait for the traffic to proceed before completeing your turn.
If you make your turn and force other drivers to back up – it’s both unsafe and unprofessional.
When making left-hand turns onto a multi-lane roads, move the unit directly into the right-hand driving lane.
When turning a semi-truck and trailer correctly, the tractor (towing unit) can go anywhere…so long as the trailer stays in its lane!
BOX THE CORNERS
When turning corners with a larger vehicle, commercial drivers no longer have the luxury of arcing through – they must now “box” or square off the corner.
Off-tracking is most pronounced in an 18-wheeler, and to get the trailer around the corner, the driver must proceed straight into the intersection, and turn the power unit at the last possible moment.
This manoeuvre compensates for the shorter path that the trailer is going to follow through the corner.
CONSEQUENCES OF INCORRECT TURNING
On a more than one occasion, students have failed to proceed straight into the intersection before turning.
On one occasion this novice driver’s error resulted in the trailer tires striking a concrete barrier.
Although no one was injured, the damages cost in excess of $300.
In Kelowna, BC, Canada (390km northeast of Vancouver) in late-March 2015, a driver cut the corner and struck and destroyed a fire hydrant.
Consequently, an entire city block flooded.
That failed turn resulted in extensive property damage.1
On a more awful note, a father died in Alamo, Georgia, USA (257km southeast of Atlanta), when he attempted to turn his tractor-trailer.
Authorities stated that “changes were made to the road and it is not made for trucks.”
From the reports, it is suspected that the speed was too fast for road conditions. Not surprising owing to “correct speed” being a critical component of turning a semi-truck and trailer correctly.
Consequently, the unit overturned, killing the driver.
His 3-year-old son survived the crash.2
CONCLUSION
If there is one thing that new drivers must leave a driving school with, it is the importance of turns.
Keep the following points in mind:
• Slow the unit down before the corner.
• Move left in your lane to turn right; move right in your lane to turn left.
• If there are two turning lanes, always, always start from the outside lane (if you’re turning left, be in the right lane; if you’re turning right, be in the left-right-turning lane)
• Map and track the intersection and its road users.
• Calculate how you can use the space in the intersection and the space from the road onto which you’re turning;
• Also, determine how you can keep hazards and obstacles and other traffic in front and on your driver’s side (sight side).
• Box the corner – drive “dead straight” into the intersection before turning.
• Observe, observe, observe – look in those mirrors and watch the trailer’s path of travel as you go around the corner.
• “Some guys can turn it on a dime or turn it right downtown.”
The line from “Give me 40 acres…” invites drivers to be that driver – the driver that moves the vehicle around corners with skill and ease.
With patience, perseverance, and practice, even novice drivers can safely manoeuvre a “big truck” around tight corners.
CLICK TO learn about truck driver’s increased “duty of care”.