Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Flight Instructor; Flight Crew Commercial
Flight Crew Last 90 Days 65; Flight Crew Total 750; Flight Crew Type 500
Situational Awareness
Aircraft Equipment Problem Less Severe; Ground Event / Encounter Loss Of Aircraft Control
Aircraft; Human Factors
Holding short of XXL on taxiway. Given clearance for takeoff. Student began taxi. Started drifting left. Applied right rudder. Kept drifting left. Applied more right rudder and brake. Kept drifting. Pulled power and full right rudder and brake. Instructor took controls and applied full right brake and rudder. Brake pedal went to floor. Left tire hit gravel and pulled plane to left. Spun plane 180 degree in gravel. No damage to aircraft; propeller; or taxiway lights observed.
C172RG Flight Instructor reported steering issue during takeoff roll.