Cessna Citation Sovereign (C680)
Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine; Flight Crew Instrument
Communication Breakdown; Other / Unknown; Situational Awareness
Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Other / Unknown
General Physical Injury / Incapacitation
Airport; Human Factors; Procedure
While calling for our taxi clearance out of ZZZ. Captain began to power up to begin our taxi. He started adding more power than normal but we were heavy with 6 passengers; lot of bags and fuel; not moving he added more power. I was about to say 'I think we might have a chock in' in when he finally pulled the power back some and realized he had the parking brake on. The lineman marshaling us out seemed concerned about something going on behind us but after briefly stopping he continued to Marshall us out of the ramp. I told the Captain 'I think you had too much power in'. On the taxi out I could see behind us the hangar door was open and there were a few people inside. We later found out a flight attendant had fallen over from our jet blast. Obviously the issue could have been solved by taking the parking brake off before adding power. It might be a good idea for them not to marshall planes out while people are walking in the hangar; though that may be unavoidable at [FBO] due to the ramp configuration.
C680 flight crew failed to release parking brake before taxi; resulting in excess power applied that knocked a person over.