Regarding solo D-unit drivers, there are some SUCCESSFUL ones running right now, so, of course a solo driver in a D-unit can make it. However, to do so, one would be wise to figure out what they are doing, and what mistakes they are avoiding, to succeed. The time to do that is before you commit to a truck.
Regarding solo operation of a liftgate, I would say that it can be done as safely as climbing in and out of a truck, if the liftgate is properly configured. Suggestions:
1. The bigger the platform, the better. The platform should be at least large enough to hold one skid and a pallet jack, with the pallet jack under the skid. That enables you to easily roll the skid onto and off the platform with the pallet jack.
2. Include cart stops on the gate (pop up devices that prevent the freight from rolling off the gate when the gate is at an angle).
3. A remote control with a wire long enough to reach all sides of the liftgate when freight is on the gate.
4. A truck box floor, frame and deck extension (if applicable) that provides a level or near-level path from the liftgate surface into the truck body (box). This so freight can be easily rolled from the lift gate into and back out of the truck.
5. Liftgate weight capacity that well exceeds the amount of freight you would ever put on the gate.
6. Keep the liftgate clean and well maintained.
7. Use a high-quality pallet jack with good wheels. Keep it clean and well maintained too. Note that pallet jacks come in a variety of configurations. Configure yours to meet your most frequent uses.
8. Don't try to move freight alone that is too heavy for you to safely handle. Personally, if the ground surface is reasonably smooth and level, a 2,000 lbs. skid is managable. Anything over that and I would look for help from the shipper to load the freight.
Our Leyman LHLP-4500 liftgate with the cart stops option and a custom made remote control (made by the trailer shop that installed the gate) does the job nicely for us. In our CR-unit, we seldom get skids that weigh over 2,000 lbs.
If you are new, a little practice with the pallet jack will have you looking like a pro in no time. If you get the chance, take an hour or two to move freight on, off, and around the inside of the truck. Practice 360 degree turns inside the truck. Practice positioning the freight just so, several times, to get the hang of it. Examine pallets to see how to best approach them with the pallet jack and position it under (pallet designs vary). If you do not practice, your pallet jack skills will come to you in time. Practice simply accelerates the process and helps you operate that much more safely.
With every liftgate load, it is wise to pause for a moment and think through what you are about to do. When shippers are standing right there watching you, it is tempting to get right to work and get out quickly. Taking 15 seconds to rehearse the job in your mind before you begin may make the difference between loading safely or getting injured.
Is your work surface wet or dry? How is the traffic around you? How heavy is the freight? Is it top-heavy? Is it evenly balanced? What kind of skid are you working with? Or, if the freight is on its own wheels, do you trust them, or do you need to put the freight on a trustworthy dolly or pallet jack? Is it best to use the remote control or pallet jack switch on the truck? Is the truck parked on level ground? If not, which way will the freight tend to roll? If the truck is parked on a hill, what will you do to keep the freight under control?
While lift gate loads present certain challenges, they only present safety risks if you proceed in an unsafe manner. Liftgates are not accidents waiting to happen. Accidents happen when people create conditions favorable for them to occur.
Yes, there are exceptions, like if the liftgate breaks in half under load, or if a liftgate free falls to the ground when it should gradually descend. Those are equipment failure accidents. But such risks should be taken in proportion.
Airplanes crash, but people still fly in them. Houses burn to the ground, but people still live in them. And truckers are seriously injured falling out of their cabs, but people still climb in and out of them. A liftgate is no different. Well maintained and safely used, a liftgate can be a worthwhile business asset.