Narrative:

I was instructing mr. X, a student from the FBO. We had landed on runway 3L after practicing pattern work. I radioed prescott tower requesting permission to relocate from 3L back to FBO. The tower granted permission to cross runway 3R, and land back at FBO. I instructed mr. X to proceed. He lifted off vertically and proceeded down runway heading, gaining speed and altitude. To my surprise, at approximately 7-10 ft, mr X applied right cyclic, putting us in a downwind position. The wind had been out of the northwest approximately 17 to 20 KTS, gusting to 25 KTS, thus putting us in an almost direct crosswind departing on runway 3. As I reached for the controls attempting to recover from mr X's downwind turn, I continued to my right to complete a 270 degree turn back into the wind. At approximately 45 degrees to 90 degrees, into the turn, I visually noticed engine and rotor RPM decaying from 3100 to 2900 RPM and dropping, experiencing partial engine failure. I responded by lowering the collective and adding throttle. The engine continued to cut out, not allowing adequate rotor RPM. I referenced my rotor RPM decay below the allowable minimum rotor RPM, at which point I executed an automatic rotation over the immediate area in which we had advanced between runway 3L and runway 3R, thus performing a forced landing in a rocky ravine. As I was making my vertical descent, it was necessary to use excessive aircraft cyclic to zero out my airspeed due to the strong winds out of the northwest. In the process of flaring the helicopter, my tail rotor came in contact with the rocks below. As we came to rest at the bottom of the ravine, I radioed the tower to notify them of the incident. They responded by asking if everyone was alright and told me they had already sent the trucks. I had a choice of performing a run-on landing or a vertical descent. I chose not to do a run-on landing simply because I ran the risk of rolling the helicopter due the rough terrain which most likely would have caused injury to my student and myself along with destroying the helicopter.

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Original NASA ASRS Text

Title: A HELI PLT DAMAGED HIS TAIL ROTOR.

Narrative: I WAS INSTRUCTING MR. X, A STUDENT FROM THE FBO. WE HAD LANDED ON RWY 3L AFTER PRACTICING PATTERN WORK. I RADIOED PRESCOTT TWR REQUESTING PERMISSION TO RELOCATE FROM 3L BACK TO FBO. THE TWR GRANTED PERMISSION TO CROSS RWY 3R, AND LAND BACK AT FBO. I INSTRUCTED MR. X TO PROCEED. HE LIFTED OFF VERTLY AND PROCEEDED DOWN RWY HDG, GAINING SPD AND ALT. TO MY SURPRISE, AT APPROX 7-10 FT, MR X APPLIED R CYCLIC, PUTTING US IN A DOWNWIND POS. THE WIND HAD BEEN OUT OF THE NW APPROX 17 TO 20 KTS, GUSTING TO 25 KTS, THUS PUTTING US IN AN ALMOST DIRECT XWIND DEPARTING ON RWY 3. AS I REACHED FOR THE CTLS ATTEMPTING TO RECOVER FROM MR X'S DOWNWIND TURN, I CONTINUED TO MY R TO COMPLETE A 270 DEG TURN BACK INTO THE WIND. AT APPROX 45 DEGS TO 90 DEGS, INTO THE TURN, I VISUALLY NOTICED ENG AND ROTOR RPM DECAYING FROM 3100 TO 2900 RPM AND DROPPING, EXPERIENCING PARTIAL ENG FAILURE. I RESPONDED BY LOWERING THE COLLECTIVE AND ADDING THROTTLE. THE ENG CONTINUED TO CUT OUT, NOT ALLOWING ADEQUATE ROTOR RPM. I REFED MY ROTOR RPM DECAY BELOW THE ALLOWABLE MINIMUM ROTOR RPM, AT WHICH POINT I EXECUTED AN AUTO ROTATION OVER THE IMMEDIATE AREA IN WHICH WE HAD ADVANCED BTWN RWY 3L AND RWY 3R, THUS PERFORMING A FORCED LNDG IN A ROCKY RAVINE. AS I WAS MAKING MY VERT DSCNT, IT WAS NECESSARY TO USE EXCESSIVE ACFT CYCLIC TO ZERO OUT MY AIRSPD DUE TO THE STRONG WINDS OUT OF THE NW. IN THE PROCESS OF FLARING THE HELI, MY TAIL ROTOR CAME IN CONTACT WITH THE ROCKS BELOW. AS WE CAME TO REST AT THE BOTTOM OF THE RAVINE, I RADIOED THE TWR TO NOTIFY THEM OF THE INCIDENT. THEY RESPONDED BY ASKING IF EVERYONE WAS ALRIGHT AND TOLD ME THEY HAD ALREADY SENT THE TRUCKS. I HAD A CHOICE OF PERFORMING A RUN-ON LNDG OR A VERT DSCNT. I CHOSE NOT TO DO A RUN-ON LNDG SIMPLY BECAUSE I RAN THE RISK OF ROLLING THE HELI DUE THE ROUGH TERRAIN WHICH MOST LIKELY WOULD HAVE CAUSED INJURY TO MY STUDENT AND MYSELF ALONG WITH DESTROYING THE HELI.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.