Individually Owned: 150,657
Corporate Owned: 137,281
Baltimore-Washington Intl Airport
Aircraft Accident/Incident Report
Baltimore, Maryland 21061
Wednesday, August 1, 2001 13:00 EDT
NTSB Narrative Summary Released at Completion of Accident
The purpose of the helicopter flight was to take aerial photographs of a large airport expansion construction project. The helicopter approached the construction site in an out-of-ground-effect hover taxi, with a quartering left tailwind. The helicopter turned to the right, and slowed to a stationary hover about 250 feet above the ground with a direct tailwind. Once in a hover, the helicopter made a right, rapid 180-degree pedal turn around the mast, stopped momentarily, then initiated another rapid pedal turn to the right. The helicopter turned at a faster rate than the initial turn, and continued into a spinning, vertical descent to the ground. Examination of the helicopter revealed no mechanical anomalies. The collective was in the full up position, and the main rotor blades exhibited signatures consistent with low rotor rpm at ground contact. A review of the pilot's company flight records revealed he had 531 hours of total flight experience, 60 hours of which were in airplanes. The pilot had 87 hours of experience in make and model. A relative wind chart published by the manufacturer depicts a helicopter facing 360 degrees over a compass rose. One shaded area of the chart depicts winds from between 120 degrees and 240 degrees, at wind speeds above 5 knots and up to 17 knots. According to a note on the chart an unanticipated right yaw may occur when operating in the shaded areas of the chart. According to FAA Advisory Circular (AC) 90-95, "Any maneuver which requires the pilot to operate in a high power, low airspeed environment with a left crosswind or tailwind creates an environment where unanticipated right yaw may occur." The AC also advised of greater susceptibility for loss of tailrotor effectiveness in right turns and the phenomena may occur in varying degrees in all single main rotor helicopters at airspeeds less than 30 knots.
NTSB Probable Cause Narrative
The pilot's improper decision to maneuver in an environment conducive to a loss of tail rotor effectiveness, and his inadequate recovery from the resultant unanticipated right yaw.
Event Information
| Type of Event | Accident |
| Event Date | 8/1/2001 |
| Event Day of the Week | Wednesday |
| Time of Event | 1300 |
| Event Time Zone | Eastern Daylight Time |
| Event City | Baltimore |
| Event State | MARYLAND |
| Event Country | -- |
| Zipcode of the event site | 21061 |
| Event Date Year | 2001 |
| Event Date Month | 8 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 391105N |
| Event Location Longitude | 0764039W |
| Event Location Airport | BALTIMORE-WASHINGTON INTL |
| Event Location Nearest Airport ID | BWI |
| Indicates whether the acc/inc occurred off or on an airport | On Airport |
| Distance from airport in statute miles | -- |
| Degrees magnetic from airport | -- |
| Airport Elevation | 146 |
| Weather Briefing Completeness | Unknown |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1254 Eastern Daylight Time |
| Direction of event from weather observation facility (degrees) | -- |
| Weather Observation Facility ID | BWI |
| Elevation of weather observation facility | 146 |
| Distance of event from weather observation facility (units?) | -- |
| Time Zone of the weather observation | EDT |
| Lighting Conditions | Day |
| Lowest Ceiling Height | -- |
| Lowest Non-Ceiling Height | 5000 |
| Sky/Lowest/Cloud Conditions | Few |
| Sky Condition for Lowest Ceiling | None |
| Visibility Runway Visual Range (Feet) | -- |
| Visibility Runway Visual Value (Statute Miles) | -- |
| Visibility (Statute Miles) | 10 |
| Air Temperature at event time (in degrees celsius) | 27 |
| Dew Point at event time (in degress fahrenheit) | 16 |
| Wind Direction (degrees magnetic) | -- |
| Variable Wind Indicator | Variable |
| Wind Speed (knots) | 6 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 30.36 |
| Density Altitude (feet) | 1146 |
| Intensity of Precipitation | -- |
| METAR weather report | -- |
| Event Highest Injury | Fatal |
| On Ground, Fatal Injuries | -- |
| On Ground, Minor Injuries | -- |
| On Ground, Serious Injuries | -- |
| Injury Total Fatal | 2 |
| Injury Total Minor | -- |
| Injury Total None | -- |
| Injury Total Serious | -- |
| Injury Total All | 2 |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 12984 |
| NTSB Notification Source | FAA EROC |
| NTSB Notification Date | Aug 1 2001 12:00AM |
| NTSB Notification Time | 1330 |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | Apr 15 2003 4:06PM |
| User who most recently changed record | NTSB\MONR |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | Baltimore, Maryland 21061 |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N89FB |
| NTSB Number | IAD01FA089 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | None |
| Flight plan Was Activated? | No |
| Damage | Destroyed |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Bell |
| Aircraft Model | 206B |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 1980 |
| Certified Max Gross Weight | 3200 |
| 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 | 4 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | 100 Hour |
| Date of Last Inspection | Oct 23 2000 12:00AM |
| Airframe hours since last inspection | 66 |
| Airframe Hours | 10949 |
| ELT Installed | Yes |
| ELT Activated | Yes |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | US Lease Co Inc |
| Aircraft Owner Street Address | Martin State Airport Box E |
| Aircraft Owner City | Baltimore |
| Aircraft Owner State | MD |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 21220 |
| Operator is an individual? | No |
| Operator Name | Helicopter Transport Services |
| Operator Same as Owner? | No |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | No |
| Operator Street Address | 701 Wilson Point Road |
| Operator City | Baltimore |
| Operator State | MD |
| Operator Country | USA |
| Operator Zip code | 21220 |
| Operator Code | -- |
| Owner has at least one certificate | -- |
| 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) | Aerial Observation |
| Second Pilot on Board | No |
| Departure Point Same as Event | No |
| Departure Airport Code | MTN |
| Departure City | Baltimore |
| Departure State | MD |
| Departure Country | USA |
| Departure Time | 1232 |
| Departure Time Zone | EDT |
| Destination Same as Local Flt | crash at destination city |
| Destination Airport Code | BWI |
| Destination City | Baltimore |
| Destination State | MD |
| Destination Country | USA |
| Specific Phase of Flight | Hover - out of ground effect |
| Report sent to ICAO? | No |
| Evacuation occurred | No |
| Date of most recent change to record | Oct 18 2002 11:14AM |
| User who most recently changed record | PEAR |
| Since inspection or accident | Time of Accident |
| Event Location Runway Number and Location | 15R |
| Runway Length | 9519 |
| Runway Width | 150 |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |