Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Flight Instructor; Flight Crew Commercial
Flight Crew Last 90 Days 116.6; Flight Crew Total 1055.2; Flight Crew Type 525.1
Training / Qualification; Distraction
Ground Event / Encounter Loss Of Aircraft Control; Ground Excursion Taxiway
Flight Crew Regained Aircraft Control
Human Factors; Aircraft
While conducting training; the trainee's brakes fully compressed and airplane veered off of the taxiway into the grass for a brief time. Using the copilot brakes we were able to get back into the taxiway without incident. No damage was found.
Cessna 402 instructor pilot reported a brake system anomaly while taxiing caused the aircraft to briefly depart the paved surface.