ENG OUT PRACTICE DURING TRAINING FLT FOR WATER LNDGS; SLOW SPD; HIGH SINK RATE; RECOVERY TOO LATE RESULTING IN HARD LNDG AND ACFT DAMAGE.

Narrative

WE WERE WORKING ON SIMULATED ENG-OUTS AFTER WATER TKOFS RESULTING IN A GLIDE TO A WATER LNDG. THE STUDENT PERFORMED THE FIRST TKOF; ENG-OUT; AND PWR-OFF LNDG QUITE WELL. THE SECOND TKOF BEGAN WELL LIKE THE FIRST. I DECIDED TO DO ANOTHER ENG FAILURE AFTER THE FLAP RETRACTION DURING THE CLB SO TO INCLUDE LOWERING THE FLAPS IN THE STUDENT'S EMER CHKLIST. THIS ACFT HAS AN ENG MOUNTED ON TOP OF THE FUSELAGE; SO A PWR REDUCTION RESULTS IN A RAPID PITCH UP ATTITUDE AND AN EQUALLY RAPID LOSS OF AIRSPD. THE PROPER RECOVERY TECHNIQUE IS TO LOWER THE NOSE WITH ALMOST FULL FORWARD ELEVATOR; ACCELERATE TO 85 MPH AND LOWER THE FLAPS FOR LNDG. THE STUDENT WAS SLOW PUSHING THE NOSE OVER RESULTING IN AN AIRSPD LOSS FROM 75 MPH TO 65 MPH IN ABOUT 2 SECONDS. AT THIS POINT; I ELECTED TO TAKE CTL OF THE ACFT. AT AN ALT OF 200 FT I APPLIED FULL PWR; PITCHED THE NOSE FURTHER DOWN AND LOWERED THE FLAPS. THE RATE OF DSCNT WAS RAPID AND UPON REACHING 65-70 MPH I CHANGED THE ATTITUDE TO LEVEL FLT TO TRY TO SLOW THE RATE OF DSCNT WITHOUT STALLING. THE ACFT BOUNCED HARD; DENTING THE HULL AND THE SPONSON. IN RETROSPECT; LEAVING A LARGER SAFETY ENVELOPE FOR THE MANEUVER; ME NOT TOTALLY REALIZING HOW MUCH DRAG THE ACFT PRODUCED; AND ME LETTING THE AIRSPD DROP TOO LOW WERE ALL CONTRIBUTING FACTORS TO THE INCIDENT.