GREAT LAKES 2T-1A-2 PLT LOST LATERAL CTL ON LNDG; WENT OFF THE RWY; HIT A DITCH; AND WOUND UP ON ITS NOSE.

Narrative

THE PLT WAS PRACTICING TKOF AND LNDGS IN A 1930'S TYPE BIPLANE. DURING LNDG ROLLOUT; AN UNEXPECTED GUST LIFTED THE L WING. BEFORE CORRECTIVE ACTION WAS TAKEN; THE ACFT HEADED OFF THE RWY TO THE R (ABOUT 30 DEGS) AND INTO THE GRASS. THE ACFT STILL POSSESSED A CONSIDERABLE AMOUNT OF ENERGY WHILE ATTEMPTING TO DIRECT IT BACK TOWARD THE RWY. AT THIS TIME THE L LNDG GEAR/WHEEL DROPPED INTO A DRAINAGE DITCH; ARRESTING FURTHER FORWARD TRAVEL AND CAME TO REST ON THE PROP AND SPINNER. THE UNEXPECTED MANEUVER OF THE ACFT; TO ME RESEMBLED A LIGHT LNDG BOUNCE WITH EXAGGERATED LATERAL OR TURNING TENDENCY. CONTRIBUTING FACTORS -- VARIABLE WIND CONDITION AND PLT'S EXPERIENCE WITH TYPE ACFT. FACTORS AFFECTING HUMAN PERFORMANCE -- LACK OF EXPERIENCE; EXPOSURE OR RECOGNITION TO THIS TYPE OF MOVEMENT. IN MY RECENT TRAINING OF TAILWHEEL ACFT; FOCUS HAD BEEN PLACED ON BOUNCE RECOVERY BUT ALWAYS IN A STRAIGHT AND FORWARD DIRECTION. TO PREVENT A RECURRENCE OF THIS TYPE OF INCIDENT; I THINK FUTURE TRAINING (CERTAINLY MINE) SHOULD ADDRESS THIS TYPE OF SIT.