What happened
Following lift-off, the pilot reported that the aircraft began a left roll while the landing gear was being retracted. The pilot attempted to correct the motion using aileron and rudder inputs and lowered the nose; however, the aircraft rolled to the right before rolling back to the left. The pilot subsequently landed the aircraft near the departure end of the runway with the landing gear still in the retracted position.
The investigation
An investigation determined that the aircraft had been loaded to a weight of approximately 12,850 lbs, which exceeded the maximum gross weight limit of 11,500 lbs. Additionally, the aircraft's center of gravity was estimated to be approximately 3 inches aft of the aft limit. The company director stated that when cargo shipments were delivered to the company, the weights were not verified prior to being loaded onto the aircraft.