Yup, that's our airplane way out there on the ramp. This is Florida, mind you, so that walk across the ramp undoes my recently completed shower and subsequent primping.
We check the outside, and we check the insides of the outsides, and then the inside inside. There are many panels to be opened up and examined, to include one that the captain I am flying with is standing up in. His legs are to the left.
Once we are through checking out the airplane, we can get it towed closer in. This particular airplane has an inoperative APU or Auxiliary Power Unit (isn't that what I wanted the Citation X for?), so we will have to adapt. An APU usually powers up the aircraft in two ways. First, the APU is started by an electric motor, with power supplied by a battery or external power source (ground power unit). After the APU accelerates to full speed, it can provide a much larger amount of power to start the aircraft's main engines, either by turning an electrical generator or by compressing air.
APUs also have several auxiliary functions. Electrical and pneumatic power is used to run the heating, cooling, and ventilation systems prior to starting the main engines. This allows the cabin to be comfortable while the passengers are boarding without the expense, noise, and danger of running one of the aircraft's main engines. Electrical power is also used to power up systems for preflight checks. http://en.wikipedia.org/wiki/Auxiliary_power_unit
Since we don't have our APU, we get towed closer to the hangar so we can take advantage of the GPU, or ground power unit and their Huffer cart, an external engine that creates large volumes of pressurized air used to start large gas turbine jet engines on some types of aircraft. http://en.wikipedia.org/wiki/Huffer The captain has been flying this airplane for more than ten years and has never had to use a Huffer cart. I guess this makes me a bearer of good luck. Well, anyway, at least it was good training.