Flight Instructor with student reported a runway excursion during takeoff while performing a simulated engine failure during multi-engine training. The instructor took control as the aircraft veered off the side of the runway with no reported damage or injuries.

Narrative

Part 141 School training flight for a Multi Engine commercial student. A stop and go landing was performed and we briefed a simulated engine failure on the takeoff and briefed the simulated procedure. I as the instructor initiated a left engine 'failure' by bringing the left engine to idle at between 20-25 kts KIAS. The student initiated an incorrect response (left rudder and did not reduce power on the right engine) and the aircraft began to veer to the left side of the runway. I as the instructor immediately intervened (added full right rudder and reduced right engine to idle and applied brakes); however at this point the momentum of veering to the left was too great and we slid about 5 to 10 feet off the left side of the runway. No damage was sustained to aircraft or airport property and no hazard was created to other aircraft. Maintenance personnel came to inspect and determined no damage was caused. Aircraft was pushed back onto the runway and taxied back to the ramp to maintenance personnel for further inspection.