SMA HIT PWR LINE DURING PRACTICE OFF ARPT FORCED EMER LNDG.

Narrative

WHILE ON AN INSTRUCTIONAL FLT I PULLED THE THROTTLE BACK TO SIMULATE AN ENG FAILURE. MY STUDENT CHOSE A FIELD; RAN THROUGH THE APPROPRIATE CHKLISTS AND SET UP FOR THE GLIDING APCH TO THE FIELD. I INSTRUCTED HIM TO PUT DOWN THE CHKLIST ON THE BASE TO FINAL TURN AND CONCENTRATE ON FLYING THE ACFT AND EVALUATING THE FIELD. WE NOTICED PWR LINES ON EITHER SIDE OF THE FIELD. THE FIELD WAS APPROX 1500 FT WIDE. WE CONTINUED THE APCH IN SPITE OF THE LINES ON EITHER SIDE. ONCE THE FIELD WAS IN NO QUESTION OF BEING MADE I INSTRUCTED HIM TO GAR. HE APPLIED FULL PWR; TURNED OFF THE CARB HEAT; AND STARTED TO ADJUST THE FLAPS FOR THE GAR. AS HE REACHED FOR THE FLAPS A BRIGHT LIGHT FLASHED IN THE COCKPIT. I IMMEDIATELY TOOK CTL OF THE ACFT AND SCANNED THE INSTS. I NOTICED THE ALTIMETER READ APPROX 320 FT. I FLEW THE ACFT WHILE I TOLD THE STUDENT TO DECLARE AN EMER. IT TOOK FULL L RUDDER AND A L BANK TO KEEP THE ACFT ON A STRAIGHT TRACK. I GAINED ALT TO INCREASE MY GLIDING DISTANCE AND TOLD MY STUDENT TO WATCH FOR EMER FIELDS. WE MADE IT BACK TO THE ARPT WITHOUT FURTHER INCIDENT. THE PROBLEM AROSE FROM INADEQUATE LIGHTING OF THE FIELD AND A POOR DECISION TO GO AROUND AS SOON AS PWR LINES WERE OBSERVED ON EITHER SIDE OF THE FIELD. THIS WAS ALSO THE FIRST TIME AN ACFT THAT I WAS IN FLEW BELOW THE MSA PRESCRIBED FOR THIS MANEUVER. HINDSIGHT BEING 20/20 I UNDERSTAND THAT THIS INCIDENT WAS CAUSED BY CARELESS AND RECKLESS OP AS A CFI/PIC. AS A RESULT OF THIS I WILL NOT LET MYSELF OR A STUDENT DSND BELOW THE MSA UNLESS PRACTICING AT AN APPROVED ARPT.