What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
(-23) Schweizer N428MS departed galletin field (bzn) bozeman, Montana enroute to Three Forks Airport (9S5) Three Forks Montana. Upon arriving at Three Forks Airport the instructor and student discussed the crosswind on how it would affect the maneuvers. N427MS took off and set up for a straight in autorotation on runway 02. Two (2) straight in autorotations were completed to power recoveries. The instructor and student then continued with 4 one hundred and eighty degree (180) autorotations entered from the right downwind; then proceeded to practice Three (3) one hundred and eighty degree (180) autorotations from the left downwind of runway 02. On the third one eighty autorotation from the left the student began cyclic flare. Just prior to the power recovery the tailrotor struck the runway. Then the instructor came on the controls, because the power recovery was already initiated by the student, the skids were beginning to level and the collective and throttle inputs were applied. The helicopter made contact with the ground and bounced into the air. The helicopter began to oscillate and spin, the instructor rolled off the throttle. Upon rolling the throttle off the aircraft settled onto the runway, left skid collapsed and aircraft rolled onto its left side. Both instructor and student exited the aircraft. No injuries to either pilot other than minor scrapes and bruises. Runway marks indicate that the tail rotor blades made contact with the pavement. Aircraft ended up on left side. Damage to the last 2 foot of each main rotor blade tip, tail boom, airframe, skids and tail rotor. No additional causal factors at this time.
As the FAA filed it
(-23) SCHWEIZER N428MS DEPARTED GALLETIN FIELD (BZN) BOZEMAN, MONTANA ENROUTE TO THREE FORKS AIRPORT (9S5) THREE FORKS MONTANA. UPON ARRIVING AT THREE FORKS AIRPORT THE INSTRUCTOR AND STUDENT DISCUSSED THE CROSSWIND ON HOW IT WOULD AFFECT THE MANEUVERS. N427MS TOOK OFF AND SET UP FOR A STRAIGHT IN AUTOROTATION ON RUNWAY 02. TWO (2) STRAIGHT IN AUTOROTATIONS WERE COMPLETED TO POWER RECOVERIES. THE INSTRUCTOR AND STUDENT THEN CONTINUED WITH 4 ONE HUNDRED AND EIGHTY DEGREE (180) AUTOROTATIONS ENTERED FROM THE RIGHT DOWNWIND; THEN PROCEEDED TO PRACTICE THREE (3) ONE HUNDRED AND EIGHTY DEGREE (180) AUTOROTATIONS FROM THE LEFT DOWNWIND OF RUNWAY 02. ON THE THIRD ONE EIGHTY AUTOROTATION FROM THE LEFT THE STUDENT BEGAN CYCLIC FLARE. JUST PRIOR TO THE POWER RECOVERY THE TAILROTOR STRUCK THE RUNWAY. THEN THE INSTRUCTOR CAME ON THE CONTROLS, BECAUSE THE POWER RECOVERY WAS ALREADY INITIATED BY THE STUDENT, THE SKIDS WERE BEGINNING TO LEVEL AND THE COLLECTIVE AND THROTTLE INPUTS WERE APPLIED. THE HELICOPTER MADE CONTACT WITH THE GROUND AND BOUNCED INTO THE AIR. THE HELICOPTER BEGAN TO OSCILLATE AND SPIN, THE INSTRUCTOR ROLLED OFF THE THROTTLE. UPON ROLLING THE THROTTLE OFF THE AIRCRAFT SETTLED ONTO THE RUNWAY, LEFT SKID COLLAPSED AND AIRCRAFT ROLLED ONTO ITS LEFT SIDE. BOTH INSTRUCTOR AND STUDENT EXITED THE AIRCRAFT. NO INJURIES TO EITHER PILOT OTHER THAN MINOR SCRAPES AND BRUISES. RUNWAY MARKS INDICATE THAT THE TAIL ROTOR BLADES MADE CONTACT WITH THE PAVEMENT. AIRCRAFT ENDED UP ON LEFT SIDE. DAMAGE TO THE LAST 2 FOOT OF EACH MAIN ROTOR BLADE TIP, TAIL BOOM, AIRFRAME, SKIDS AND TAIL ROTOR. NO ADDITIONAL CAUSAL FACTORS AT THIS TIME.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.