ON LNDG ROLLOUT; BE36 STUDENT PLT INADVERTENTLY RETRACTED THE LNDG GEAR WHEN DIRECTED TO RETRACT THE FLAPS BY THE INSTRUCTOR PLT.

Narrative

ON A TRAINING FLT; AFTER LNDG AND WHILE ROLLING OUT; I ASKED MY STUDENT TO RETRACT MY FLAPS (I WAS FLYING THE PLANE). THE STUDENT ACCIDENTALLY RETRACTED THE LNDG GEAR INSTEAD OF THE FLAPS. WE WERE ROLLING APPROX 50 KTS; AND APPARENTLY HIT A BUMP IN THE RWY THAT UNLOADED THE WT OF THE PLANE ON THE GEAR; AND CAUSED IT TO RETRACT. THE NOSEWHEEL COLLAPSED AND THE PROP STRUCK THE GND SEVERAL TIMES. THE MAIN GEAR PARTIALLY COLLAPSED. NO SIGNIFICANT STRUCTURAL DAMAGE WAS OBSERVED ALTHOUGH THE PROP STRIKE MOST LIKELY DESTROYED THE ENG. IN THE FUTURE; I WILL NOT ASK A STUDENT TO RETRACT THE FLAPS ON ROLLOUT; UNLESS IT IS ABSOLUTELY NECESSARY AND THE STUDENT CONFIRMS THEIR ACTIONS BEFORE TAKING THEM. THE ABOVE OCCURRED AFTER LNDG ON ROLLOUT. SUPPLEMENTAL INFO FROM ACN 677796: THIS WAS MY FIRST FLT IN A RETRACTABLE GEAR AIRPLANE. ON THE FLT DOWN IN A BE36; I WAS INSTRUCTED IN THE OP OF THE FLAPS AND OPERATED THEM AFTER LNDG. WHEN WE LANDED; WE CHANGED PLANES TO A BE36 THAT WAS AN OLDER MODEL. AFTER LNDG; DURING ROLLOUT AT ABOUT 50 KTS THE PLT INSTRUCTED ME TO RETRACT THE FLAPS. I RETRACTED THE GEAR. IN THIS MODEL OF BONANZA THE GEAR IS ON THE R SIDE AND THE FLAPS ARE ON THE L UNLIKE THE OTHER MODEL. FACTORS: FATIGUE FROM THE LACK OF SLEEP. UNFAMILIARITY OF THE AIRPLANE SYS (GEAR).