Citation Excel (C560XL)
Flight Crew Air Transport Pilot (ATP)
Training / Qualification; Human-Machine Interface
Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Other / Unknown
Flight Crew Became Reoriented
Human Factors
The passengers were onboard and seated. I was in the process of checking ID's and briefing the weather. The cabin door was open when the PIC called to me from outside the aircraft. His words were '[my name;] brakes.' Thinking he wanted me to check that the brakes were set; I stopped the briefing and went forward to check the parking brake handle. The brakes were not set; so I climbed into the left seat to set them. As I did this; I noticed the aircraft moving forward. I applied brakes in positive manner and the aircraft stopped. I explained to the passengers the reason for the action. I don't remember anything they may have said; and I went on with the safety briefing. Set the brakes as early in the preflight stage of the flight as possible. Insure the brakes are set prior to removing the chocks. Insure one pilot is in the cockpit prior to pulling the chocks.
CE560 First Officer; while in the cabin briefing the passengers; hears the Captain yell 'brakes' from outside the aircraft. Moving to the cockpit; the aircraft is noted to be moving and the parking brake is set.