# Accident 20000508036159A: Hughes 500N, Los Angeles, CA, May 8, 2000 - Type: FAA accident report (Accident/Incident Data System), as reported - Date: May 8, 2000, 09:25 local time - Place: Los Angeles, CA - Damage: Substantial damage - Phase of flight: Sfl Cruise - Operating rules: General operating rules (Part 91) - Location: 34.0522° N, 118.2437° W: Placed by OpenAirDocs: center of Los Angeles, CA, within about 12 miles (OpenAirDocs) - Nearby events: https://openairdocs.org/map.md?lat=34.0522&lon=-118.2437&mi=10 - Aircraft: N955SD, a cancelled registration (https://openairdocs.org/deregistered/N955SD-2004-07-26) (OpenAirDocs) - Registry model: Mcdonnell Douglas Helicopter 500N (registry code 3027374, https://openairdocs.org/model/mcdonnell-douglas-helicopter-500n) (OpenAirDocs) - Registry engine: Allison 250-C20 series (registry code 03020, https://openairdocs.org/engine/allison-250-c20-series) (OpenAirDocs) - Reported make and model: HUGHES 500N - Reported engine: ALLSN 250C20 - People aboard: 2 - Fatal injuries: 0 - Pilot flight hours: 13,494 total, 865 in this make and model, 80 in the last 90 days - NTSB investigation: [NTSB LAX00TA186](https://openairdocs.org/ntsb/LAX00TA186) (OpenAirDocs) - FAA source: FAA Aviation Safety Information Portal (https://asip.faa.gov/) - Page: https://openairdocs.org/incident/20000508036159A ## Narrative As the FAA filed it, in capitals; the FAA replaces private details with ^PRIVACY DATA OMITTED^. (-23) ON MAY 8, 2000 AT APPROX. 9:25 AM PDT, A MCDONNELL DOUGLAS 520N HELICOPTER, N955SD, SUSTAINED SUBSTANTIAL DAMAGE WHILE PERFORMING OFF-AIRPORT TRAINING IN EAST LOS ANGELES, CA. THE HELICOPTER WAS BEING OPERATED BY THE LOS ANGELES COUNTY SHERIFF'S DEPT. AS A PUBLIC-USE AIRCRAFT UNDER FAR PART 91. THE COMMERCIALLY RATED FLIGHT INSTRUCTOR AND COMMERCIALLY RATED PILOT TRAINEE WERE NOT INJURED. THE LOCAL AREA INSTRUCTIONAL FLIGHT ORIGINATED AT THE SHERIFF'S MAIN BASE AT THE LONG BEACH AIRPORT IN LONG BEACH, CA. VISUAL METEOROLOGICAL CONDITIONS PREVAILED AND NO FLIGHT PLAN WAS FILED. THE FLIGHT INSTRUCTOR REPORTED THAT THE PURPOSE OF THE FLIGHT WAS TO PRACTICE EMERGENCY PROCEDURES AS PART OF ROUTINE INTERDEPARTMENTAL TRAINING. THEY WERE CONDUCTING TRAINING IN AN OPEN FIELD ON PROPERTY OWNED BY THE SHERIFF'S DEPT. THE FLIGHT INSTRUCTOR STATED THAT THEY OFTEN UTILIZED THE FIELD FOR FLIGHT TRAINING (OFF-AIRPORT OPERATIONS) AND HAD USED THE SAME FIELD ONE WEEK EARLIER. HE REPORTED THAT THEY PERFORMED A HIGH RECONNAISSANCE OF THE LANDING AREA PRIOR TO THE LANDING. HE NOTED NOTHING UNUSUAL ABOUT THE TERRAIN BELOW NOR DID HE NOTICE ANYTHING UNSUITABLE ABOUT THE LANDING AREA. THE FLIGHT INSTRUCTOR STATED THAT HE SIMULATED AN ENGINE FAILURE (BY ROLLING OFF THE THROTTLE) AT APPROX. 10-15 FEET ABOVE THE LANDING AREA. THE PILOT TRAINEE, WHO WAS ON THE CONTROLS AT THE TIME, RESPONDED AND PERFORMED AN AUTOROTATIVE LANDING. THE AIRCRAFT TOUCHED DOWN WITH FORWARD SPEED WHICH CAUSED THE HELICOPTER TO SLIDE A FEW FEET, THEN STOP ABRUPTLY. TALL WEEDS AND GROUND COVERED HAD PREVENTED THE HELICOPTER FROM SLIDING FORWARD WITH THE RESULTING MOMENTUM CAUSING THE HELICOPTER TO STOP ABRUPTLY AND PITCH FORWARD. AS THE HELICOPTER PITCHED FORWARD, THE INSTRUCTOR PILOT POSITIONED THE CYCLIC CONTROL REARWARD. WHEN THE HELICOPTER SETTLED BACK TO A LEVEL ATTITUDE, THE MAIN ROTOR BLADES FLEXED DOWN AS A RESULT OF DECREASING RPM AND CUT OFF THE TAILBOOM. THE FLIGHT INSTRUCTOR REPORTED THAT NEITHER OF THE TWO PILOTS HAD SEEN THE HIGH VEGETATION IN THE LANDING AREA EVEN THOUGH THEY HAD MADE SMILAR LANDING IN THE SAME AREA BEFORE. END. (.4) ON MAY 8, 2000, AT 0925 HOURS PACIFIC DAYLIGHT TIME, A MCDONNELL DOUGLAS 500N HELICOPTER, N955SD, SUSTAINED SUBSTANTIAL DAMAGE WHILE PERFORMING OFF-AIRPORT LANDING TRAINING IN LOS ANGELES, CALIFORNIA. THE HELICOPTER WAS BEING OPERATED BY THE LOS ANGELES COUNTY SHERIFF'S DEPARTMENT AS A PUBLIC-USE AIRCRAFT UNDER THE PROVISIONS OF 14 CFR PART 91. THE COMMERCIAL RATED FLIGHT INSTRUCTOR AND COMMERCIAL RATED PILOT TRAINEE WERE NOT INJURED. THE LOCAL AREA INSTRUCTIONAL FLIGHT ORIGINATED AT THE LONG BEACH, CALIFORNIA, AIRPORT, ABOUT 0830. VISUAL METEOROLOGICAL CONDITIONS PREVAILED AND NO FLIGHT PLAN WAS FILED. THE FLIGHT INSTRUCTOR REPORTED THAT THE PURPOSE OF THE FLIGHT WAS TO PRACTICE EMERGENCY PROCEDURES AS PART OF ROUTINE INTRADEPARTMENTAL TRAINING. THEY WERE CONDUCTING THE TRAINING IN AN OPEN FIELD ON PROPERTY OWNED BY THE SHERIFF'S DEPARTMENT. THE FLIGHT INSTRUCTOR STATED THAT THEY OFTEN UTILIZED THE FIELD FOR FLIGHT TRAINING PURPOSES, AND REPORTED THAT HE HAD DONE SOME TRAINING THERE ABOUT 1 WEEK PRIOR TO THE ACCIDENT. HE REPORTED THAT THEY PERFORMED A HIGH RECONNAISSANCE OF THE FIELD PRIOR TO LANDING; AT THAT TIME HE NOTED NOTHING UNSUITABLE ABOUT THE TERRAIN. THE FLIGHT INSTRUCTOR STATED ABOUT 10 TO 12 FEET ABOVE GROUND LEVEL (AGL), HE REDUCED THE THROTTLE TO GROUND IDLE TO SIMULATE A TOTAL POWER LOSS. THE PILOT TRAINEE WAS ON THE CONTROLS; HE LANDED THE HELICOPTER WITH NO PROBLEMS. THE FLIGHT INSTRUCTOR STATED THAT THE HELICOPTER SLID FORWARD ONLY A FEW FEET, THEN STOPPED ABRUPTLY. THE SKIDS HAD BECOME ENTANGLED IN 18-INCH-TALL GRASS AND IMBEDDED VINES, CAUSING UNEXPECTED FRICTION. HE STATED THAT THE NATURAL TENDENCY TO INPUT AFT CYCLIC TO STOP THE AIRCRAFT FROM GOING OVER CAUSED THE MAIN ROTOR BLADES TO CONTACT THE TAIL BOOM. THE FLIGHT INSTRUCTOR REPORTED THAT NEITHER HE NOR THE PILOT TRAINEE HAD SEEN THE HIGH VEGETATION BEFORE LANDING, NOR HAD THEY EVER NOTED IT THERE IN THE FIELD BEFORE. ## The NTSB's investigation of this event (1) From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. - [NTSB LAX00TA186](https://openairdocs.org/ntsb/LAX00TA186), May 8, 2000: McDonnell Douglas 500N (N955SD), Los Angeles, CA, substantial damage. Probable cause: The combined failure of the operator management and the check pilot to ensure the landing area was suitable for the slide on landing. Factors were the high vegetation that entangled the skids,… From the FAA Accident/Incident Data System. Reports are matched to registry aircraft by N-number and event date, checked against the reported make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. For accidents, the NTSB's own investigation is the fuller record. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.