Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Brooklyn, New York 11226
Tuesady, May 4, 2004 18:20 EDT
NTSB Narrative Summary Released at Completion of Accident
The helicopter was hovering at 1,000 to 1,200 feet, during an electronic news gathering flight, when it experienced a loss of hydraulic system power. The pilot stated he did not have any specific recollection regarding the beginning of the accident sequence. He said that he felt the helicopter was not responding to his control inputs, "the way it should be." He also did not recall reporting any specific problems over the radio; however, review of communication recordings revealed that the pilot stated he experienced a "tail rotor failure." Another helicopter captured the accident sequence from its onboard video camera. The accident helicopter was observed entering a steep descent and quickly leveling off. A fairly constant, level attitude and heading were briefly maintained before the helicopter came to an unstable hover and began an approximate two revolution left rotation about its vertical axis. During the rotation, the helicopter descended and struck the roof parapet of a 4-story building, before it impacted and came to rest on the roof of an adjacent 2-story building. Examination of the helicopter's hydraulic system revealed that the hydraulic pump drive belt had been installed inside-out and failed due to an overload, leading to a full hydraulic system failure. According to Eurocopter's emergency procedures for the helicopter, the pilot action following a hydraulic system failure would be to "calmly reduce collective pitch and adjust the airspeed to between 40 and 60 knots in level flight" and then cut off the hydraulic pressure, by moving the toggle switch located on the collective pitch lever to off. The procedures further state that when the accumulators are exhausted, the control forces become significantly higher, but "not unmanageable." The helicopter could be controlled without the main and tail rotor servo actuators being hydraulically powered, but this would require the pilot to apply "non-negligible" forces that are substantially different than the forces required with the hydraulic system operating properly. The hydraulic system toggle switch was found in the "on" position. The "flat" hydraulic pump drive belt had accumulated about 440 hours, and had a service life limit of 600 hours. On May 11, 2004, Eurocopter issued a service bulletin which recommended the installation of a"Poly-V" hydraulic pump belt. The improved belt comprised multiple longitudinal "V" shapes on its inner surface that mated with similar surfaces on the hydraulic pump pulley and had a service life limit of 1,500 hours. Eurocopter recommended that all "flat" drive belts be replaced with the "Poly-V" belts.
NTSB Probable Cause Narrative
The pilot's failure to maintain control of the helicopter after a loss of hydraulic system pressure due to a failure of the hydraulic pump belt. Factors in this accident were the pilot's misidentification of a hydraulic failure, the pilot's subsequent failure to perform the appropriate emergency procedure, and the improper installation of the hydraulic pump belt by maintenance personnel.
Event Information
| Type of Event | Accident |
| Event Date | 5/4/2004 |
| Event Day of the Week | Tuesday |
| Time of Event | 1820 |
| Event Time Zone | Eastern Daylight Time |
| Event City | Brooklyn |
| Event State | NEW YORK |
| Event Country | -- |
| Zipcode of the event site | 11226 |
| Event Date Year | 2004 |
| Event Date Month | 5 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 403839N |
| Event Location Longitude | 0735711W |
| Event Location Airport | -- |
| Event Location Nearest Airport ID | -- |
| Indicates whether the acc/inc occurred off or on an airport | Off Airport/Airstrip |
| Distance from airport in statute miles | -- |
| Degrees magnetic from airport | -- |
| Airport Elevation | -- |
| Weather Briefing Completeness | Unknown |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1829 Eastern Daylight Time |
| Direction of event from weather observation facility (degrees) | 105 |
| Weather Observation Facility ID | JFK |
| Elevation of weather observation facility | 13 |
| Distance of event from weather observation facility (units?) | 9 |
| Time Zone of the weather observation | EDT |
| Lighting Conditions | Day |
| Lowest Ceiling Height | 25000 |
| Lowest Non-Ceiling Height | 6500 |
| Sky/Lowest/Cloud Conditions | Few |
| Sky Condition for Lowest Ceiling | Broken |
| Visibility Runway Visual Range (Feet) | -- |
| Visibility Runway Visual Value (Statute Miles) | -- |
| Visibility (Statute Miles) | 10 |
| Air Temperature at event time (in degrees celsius) | 15 |
| Dew Point at event time (in degress fahrenheit) | -3 |
| Wind Direction (degrees magnetic) | 310 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 14 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Gusting |
| Wind Gust (knots) | 20 |
| Altimeter Setting at event time (in. Hg) | 29.96 |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | -- |
| METAR weather report | -- |
| Event Highest Injury | Serious |
| On Ground, Fatal Injuries | -- |
| On Ground, Minor Injuries | -- |
| On Ground, Serious Injuries | -- |
| Injury Total Fatal | -- |
| Injury Total Minor | 1 |
| Injury Total None | -- |
| Injury Total Serious | 2 |
| Injury Total All | 3 |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 19076 |
| NTSB Notification Source | NTSB |
| NTSB Notification Date | May 4 2004 12:00AM |
| NTSB Notification Time | 1825 |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | Jan 31 2006 7:35AM |
| User who most recently changed record | NTSB\JOHB |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | Farmingdale |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N4NY |
| NTSB Number | NYC04FA117 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | None |
| Flight plan Was Activated? | -- |
| Damage | Destroyed |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Eurocopter |
| Aircraft Model | AS-350BA |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 2121 |
| Certified Max Gross Weight | 4630 |
| Aircraft Category | Helicopter |
| Aircraft Registration Class | U.S. Registered/U.S. Soil |
| Aircraft is a homebuilt? | No |
| Flight Crew Seats | -- |
| Cabin Crew Seats | -- |
| Passenger Seats | -- |
| Total number of seats on the aircraft | 5 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | Continuous Airworthiness |
| Date of Last Inspection | Apr 1 2004 12:00AM |
| Airframe hours since last inspection | 48 |
| Airframe Hours | 8377 |
| ELT Installed | No |
| ELT Activated | -- |
| ELT Aided Location of Event Site | -- |
| ELT Type | -- |
| Aircraft Owner Name | Horsham Valley Airways Inc. |
| Aircraft Owner Street Address | 450 Caredean Drive |
| Aircraft Owner City | Horsham |
| Aircraft Owner State | PA |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 19044 |
| Operator is an individual? | No |
| Operator Name | Helinet Aviation |
| Operator Same as Owner? | No |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | No |
| Operator Street Address | 16425 Hart Street |
| Operator City | Van Nuys |
| Operator State | CA |
| Operator Country | USA |
| Operator Zip code | 91406 |
| Operator Code | -- |
| Owner has at least one certificate | None |
| Other Operator of large aircraft? | -- |
| Certified for Part 133 or 137 Operation | -- |
| Operator Certificate Number | -- |
| Indicates whether an air carrier operation was scheduled or not | -- |
| Indicates Domestic or International Flight | -- |
| Operator carrying Pax/Cargo/Mail | -- |
| Type of Flying (Per_Bus / Primary) | Other Work Use |
| Second Pilot on Board | No |
| Departure Point Same as Event | No |
| Departure Airport Code | TEB |
| Departure City | Teterboro |
| Departure State | NJ |
| Departure Country | USA |
| Departure Time | 1630 |
| Departure Time Zone | EDT |
| Destination Same as Local Flt | dest & departure same, accident can occur anywhere |
| Destination Airport Code | -- |
| Destination City | -- |
| Destination State | -- |
| Destination Country | -- |
| Specific Phase of Flight | Hover |
| Report sent to ICAO? | No |
| Evacuation occurred | No |
| Date of most recent change to record | Oct 15 2005 5:39PM |
| User who most recently changed record | MUZD |
| Since inspection or accident | Last Inspection |
| Event Location Runway Number and Location | NA |
| Runway Length | -- |
| Runway Width | -- |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |