What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
(-23) Mr. Johnson, certificate #205523322, the pilot of N805JJ, a home built helicopter, was on a VFR flight from klingerstown, PA to Shermans Dale, PA. He entered the pattern for the haunstein airport (OPA2), and on short final, about 20-30 feet AGL, the engine failed without warning. The pilot reported no enroute problems nor any warning signs like sputtering prior to the failure. The aircraft landed hard and collapsed the gear. The mainrotor blade struck the tail boom. The aircraft rolled onto its left side and the tailboom bent around the right side of the aircraft with the tail rotor drive shaft entering the cockpit area and protruded throught the cockpit glass overhead. The tailboom and tailrotor gear box separated from the aircraft. Both main rotorblades recieved damage. The gas tank was approximately 1/3 rd full. There was fuel in the glass bulb along the fuel lines. There was sufficient engine oil in the oil tank. The throttle linkage was still intact.(.4)after 45 minutes of flight, and on final approach, the engine failed. The helicopter landed hard, the main rotor struck the tail boom, and the helicopter rolled over on its left side. Fuel and oil were available, and throttle linkage was intact. The pilot/owner had recently installed a power enhancement package to the Rotax 582 ul dcdi engine, and adjusted the needle jets to produce suitable egts. Based on subsequent research, the pilot stated that engine problems could have occured going from half, to full throttle rapidly because main jet was too restrictive to allow enough fuel to pass through quickly. The NTSB database revealed 23 mini-500 accidents in 1997 and 1998. Within that list, 11 involved a loss of engine power. The Rotax 582 operator's manuel stated: 'danger! This engine, by its design, is subject to sudden stoppage! Engine stoppage can result in crash landings. Such crash landings can lead to serious bodily injury or death. Never fly the aircraft equipped with this engine at locations, airspeeds, altitudes, or other circumstances from which a successful no-power landing cannot be made, after sudden engine stoppage.'
As the FAA filed it
(-23) MR. JOHNSON, CERTIFICATE #205523322, THE PILOT OF N805JJ, A HOME BUILT HELICOPTER, WAS ON A VFR FLIGHT FROM KLINGERSTOWN, PA TO SHERMANS DALE, PA. HE ENTERED THE PATTERN FOR THE HAUNSTEIN AIRPORT (OPA2), AND ON SHORT FINAL, ABOUT 20-30 FEET AGL, THE ENGINE FAILED WITHOUT WARNING. THE PILOT REPORTED NO ENROUTE PROBLEMS NOR ANY WARNING SIGNS LIKE SPUTTERING PRIOR TO THE FAILURE. THE AIRCRAFT LANDED HARD AND COLLAPSED THE GEAR. THE MAINROTOR BLADE STRUCK THE TAIL BOOM. THE AIRCRAFT ROLLED ONTO ITS LEFT SIDE AND THE TAILBOOM BENT AROUND THE RIGHT SIDE OF THE AIRCRAFT WITH THE TAIL ROTOR DRIVE SHAFT ENTERING THE COCKPIT AREA AND PROTRUDED THROUGHT THE COCKPIT GLASS OVERHEAD. THE TAILBOOM AND TAILROTOR GEAR BOX SEPARATED FROM THE AIRCRAFT. BOTH MAIN ROTORBLADES RECIEVED DAMAGE. THE GAS TANK WAS APPROXIMATELY 1/3 RD FULL. THERE WAS FUEL IN THE GLASS BULB ALONG THE FUEL LINES. THERE WAS SUFFICIENT ENGINE OIL IN THE OIL TANK. THE THROTTLE LINKAGE WAS STILL INTACT.(.4)AFTER 45 MINUTES OF FLIGHT, AND ON FINAL APPROACH, THE ENGINE FAILED. THE HELICOPTER LANDED HARD, THE MAIN ROTOR STRUCK THE TAIL BOOM, AND THE HELICOPTER ROLLED OVER ON ITS LEFT SIDE. FUEL AND OIL WERE AVAILABLE, AND THROTTLE LINKAGE WAS INTACT. THE PILOT/OWNER HAD RECENTLY INSTALLED A POWER ENHANCEMENT PACKAGE TO THE ROTAX 582 UL DCDI ENGINE, AND ADJUSTED THE NEEDLE JETS TO PRODUCE SUITABLE EGTS. BASED ON SUBSEQUENT RESEARCH, THE PILOT STATED THAT ENGINE PROBLEMS COULD HAVE OCCURED GOING FROM HALF, TO FULL THROTTLE RAPIDLY BECAUSE MAIN JET WAS TOO RESTRICTIVE TO ALLOW ENOUGH FUEL TO PASS THROUGH QUICKLY. THE NTSB DATABASE REVEALED 23 MINI-500 ACCIDENTS IN 1997 AND 1998. WITHIN THAT LIST, 11 INVOLVED A LOSS OF ENGINE POWER. THE ROTAX 582 OPERATOR'S MANUEL STATED: 'DANGER! THIS ENGINE, BY ITS DESIGN, IS SUBJECT TO SUDDEN STOPPAGE! ENGINE STOPPAGE CAN RESULT IN CRASH LANDINGS. SUCH CRASH LANDINGS CAN LEAD TO SERIOUS BODILY INJURY OR DEATH. NEVER FLY THE AIRCRAFT EQUIPPED WITH THIS ENGINE AT LOCATIONS, AIRSPEEDS, ALTITUDES, OR OTHER CIRCUMSTANCES FROM WHICH A SUCCESSFUL NO-POWER LANDING CANNOT BE MADE, AFTER SUDDEN ENGINE STOPPAGE.'
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.