I use Cat Trax with a T-handle.

The T-handle has bearings, a T-section that goes over the axle and holds the handle assembly, the pole part of the handle, a small tube that goes through the end of the pole at 90 degrees, and a couple of grips. The instructions have you slide the T-section over the axle and capture the bearings between the axle and the T-section, allowing free rotation between the axle and the T-handle. This would be critical if the axle turned with the wheels, but it doesn’t. It does allow the cradles and axle to rotate freely relative to the handle, which I have found to be a detriment to keeping the cradles oriented so you can load the boat. This system still requires a second person to orient the cradles while getting the boat on the wheels.

The solution is to prevent the T-section from rotating around the axle. It is critical that the T-section be oriented properly so you can maneuver the boat with the hulls level. To do so, I assembled the T-handle per the manufacturer’s instructions, put the boat on the Cat Trax so that the boat was balanced with the boat level, and had the end of the handle near waist level. Then I marked the orientation of the T-section relative to the axle. This done, I took the Cat Trax and T-section and drilled through the T-section, bearings, and axle and fixed the orientation with a long bolt. Now, when everything is assembled, you can move the Cat Trax around with the cradles oriented the way you want. Just make sure the boat is balanced on the cradles to minimize the effort and the load on the T-section.

Several of the single-handers in CRAM use this type of rig and it works well. I started doing this when I had the Nacra 5.5 Uni and continued it for my I-17R. I tried this on my A-Class and the weight of the handle would rock the cradles so the hulls were resting only on the rear edge of the cradles! Now I have a lightweight T-handle and the handle remains in the air when the boat is parked on the wheels and the stearns are on foam cushions.