When you’re in the right lane next to mine on the open highway (typically on interstates or major highways with two or more lanes in each direction, in sparse traffic, usually in the countryside) or in heavier traffic, I may be passing you or you may be passing me. While passing on the left is the safer option, many drivers pull up on my right side, either to pass or to prepare to exit the highway. When you have advanced on the right from alongside the rear of my trailer to the trailer midships (middle) section and on to the front of my trailer (even with the trailer headwall and just behind my tractor’s drive wheels), your vehicle’s image has left my large right mirror completely through its outer (right) edge, but remains in the small convex mirror below it and also in the small convex mirror over my tractor’s right front fender for secondary use. Once in the small convex mirrors alone, the image has diminished (stands out less well) within my total mirrored field of vision.
When I am passing you, your vehicle will progress from direct view out my windshield, then with the top of your (standard or large size) vehicle directly visible out my right side window and an image in the small convex mirror over my tractor’s right fender, and finally to a primary image in the small convex mirror below my large right mirror in addition to the image in the right fender mirror. At this point your vehicle is alongside the front of my trailer. (NOTE: Remember from the Vision tip in the Truck Handling Characteristics and Limitations chapter that if you’re driving a sports car or other low, small vehicle, it virtually disappears from direct view with only a partial fender mirror image when you’re alongside the front of my tractor.)
Like its counterpart on my left side, the space alongside my trailer extending from the midships (middle) to the front could be called “no man’s land.” Not only are you less visible there, but the relative distances our vehicles have to travel to enable me to move right into your lane are the greatest of all zones on my right side. You have to pass me or I have to pass you. This can cause a critical delay in a lane change emergency.
There are non-emergency lane change delays. With my truck’s speed limitation, I can’t pass you in any timely fashion unless your speed is noticeably slower than mine. Many drivers, unconsciously or not, speed up when they see me swing out to pass them on their left. Then some ease off after a while to let me complete the pass while others continue on ahead of me. So I may or may not be able to return to the right lane ahead of you. If our speeds are relatively equal I may slow down to let you by me. Because of these maneuvering limitations, it’s best for you not to settle in this zone.
This zone poses other risks. True, you are able to see the road ahead of my truck, but you show up less well in my small convex mirrors. (It is important to remember that you generally show up less well in my right side mirrors than in the left mirrors.) In wet or snowy weather your vehicle may still be hit by water or snow thrown sideways from my truck, which could obscure your view of the road ahead and my view of you. Your vehicle may be hit by shrapnel thrown sideways from a blowout of a drive tire or even a steer tire.
Your vehicle will be in front of the midships trailer turn signal/emergency flasher light, and that light may or may not be in your mirrored line of sight and the ambient (scattered) light from it is not very noticeable in daylight. The next light on my tractor’s right side in front of the cab door doesn’t stand out strongly in daylight. It is generally best to move out of this and other risk zones alongside my truck as soon as it is practical, safe and lawful to do so.
For routine returns to the right after moving left for situations such as emergency vehicles or highway maintenance equipment and personnel or other vehicles and people on the right shoulder, I should be able to move over behind you by slowing down while you continue ahead.
In an emergency in a left lane, I will likely have to depend on you to continue ahead briskly while I brake hard to swerve to the right behind you. (There may not be time for me to signal and you to notice.) If you brake really hard I might be able to swerve ahead of you, but this will be more challenging. First you will have to recognize and react swiftly to the situation, and then I will have to “clear” you (verify that you are behind my trailer tail). If we can pull it off though, this option gives you a crucial advantage—you will be safely out of my truck’s long slowing/stopping path.
Risk zones on a truck’s right side are more hazardous than those on its left.
You are in “no man’s land” alongside the front of a trailer because you and the truck driver cannot quickly get out of each other’s way in an emergency.
There are a number of other reasons not to settle in this risk zone, including the possibility that in daylight you may not instantly notice a truck’s turn signal/emergency flasher lights.
As a general rule, move out of this and all other risk zones around a truck as soon as it is practical, safe and lawful to do so.
When a truck trailing your vehicle moves into the lane to your left to pass you, let the driver complete the pass and return to your lane in front of you.