Many commercial passenger planes tend to stay connected to a ground power unit (GPU) while docked at the terminal, even if it’s for a quick turnaround. However, there are instances where you’ll see a plane “pass” on connecting to a GPU. Here are some of the most common reasons why.
Well, most of the time, passenger planes will be connected to either a portable battery pack or a built-in GPU, but there are exceptions to this case. Normally, the most common reason you’ll find a plane disconnected from the GPU itself would be if the unit itself wasn’t working. Planes need at least 400HZ AC current at a high amperage rate so one can’t just plug into the standard electrical mains. Instead, a dedicated GPU is utilized as the middle-man, which incorporates a variety of safety features so the equipment doesn’t become damaged even if the unit becomes unexpectedly disconnected.
Coordinating the Ground Crew
Another reason would be if the plane were to schedule a quick turn, the pilots would signal to the ground crew not to even bother. High winds can also prevent the ground crew from being able to connect the air conditioning hoses to the aircraft, which then results in the jet’s APU being the primary source of electricity within the plane. This essentially saves the ground crew a couple of minutes of wasted time by quickly fastening the GPU then unfastening it after a brief minute or two. Start Pac, a premium portable power supplier, manufactures units that are both quick to connect and disconnect for any aircraft.
Whether it’s a lithium twin pack or any other high amperage unit, the process is still the same and, remarkably, requires an entire team to coordinate the setup process. Saving a few minutes could potentially make a difference in the overall maintenance procedure.