Individually Owned: 150,657
Corporate Owned: 137,281
Bedford/Hanscom Airport
Aircraft Accident/Incident Report
Bedford, Massachusetts 01730
Wednesday, April 28, 2004 15:03 EDT
NTSB Narrative Summary Released at Completion of Accident
During the first takeoff after the installation of an overhauled engine, about 400 feet, the engine rpm dropped, then went to zero. The pilot turned back toward the airport and unsuccessfully attempted an engine restart with the boost pump in the "high" position. The airplane subsequently landed perpendicular to a runway, all three landing gear collapsed, and the airplane came to rest between two parked airplanes. During a post-accident examination, the cockpit fuel boost pump lever was found in the "high" position, and there was no evidence of fuel spillage or spray within the engine compartment. In addition, torque paste on the engine-driven fuel pump's return line B-nut fitting was found to be 1/4 turn counter-clockwise (loosened) in relation to the torque paste on the receiving end of a 90-degree elbow fitting. When the B-nut was hand-tightened, the torque paste on both fittings were aligned. When the B-nut was further tightened with a wrench, the paste was misaligned again, but about 1/4 turn further clockwise. Multiple engine runs revealed that when the B-nut was fully tightened with a wrench, and when it was also hand-tightened to the point where the B-nut paste was aligned with the 90-degree fitting paste, the engine ran smoothly. When the B-nut was loosened to a point nearly to where it was initially found, the engine quit. During subsequent testing, while the B-nut was being loosened and the engine started to quit, the boost pump was turned on to the "high" position. The engine then ran, but fuel was sprayed from the fitting. When the B-nut was further backed off, the engine would quit and could not be restarted, even with the boost pump operating. Maintenance facility personnel subsequently conducted similar tests on another airplane with a similar fuel system. When the B-nut was loosened sufficiently to allow fuel leakage, the engine quit. However, during those tests where the engine began to quit and the auxiliary fuel pump switch was placed in the high position, the engine continued to run.
NTSB Probable Cause Narrative
The mechanic's failure to properly torque the engine-driven fuel pump's return line B-nut fitting.
Event Information
| Type of Event | Accident |
| Event Date | 4/28/2004 |
| Event Day of the Week | Wednesday |
| Time of Event | 1503 |
| Event Time Zone | Eastern Daylight Time |
| Event City | Bedford |
| Event State | MASSACHUSETTS |
| Event Country | -- |
| Zipcode of the event site | 01730 |
| Event Date Year | 2004 |
| Event Date Month | 4 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 422748N |
| Event Location Longitude | 0711736W |
| Event Location Airport | Bedford/Hanscom |
| Event Location Nearest Airport ID | BED |
| 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 | 133 |
| Weather Briefing Completeness | Unknown |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1503 Eastern Daylight Time |
| Direction of event from weather observation facility (degrees) | -- |
| Weather Observation Facility ID | BED |
| Elevation of weather observation facility | 130 |
| 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 | 7000 |
| Sky/Lowest/Cloud Conditions | Scattered |
| 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) | 11 |
| Dew Point at event time (in degress fahrenheit) | -4 |
| Wind Direction (degrees magnetic) | 350 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 11 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Gusting |
| Wind Gust (knots) | 22 |
| Altimeter Setting at event time (in. Hg) | 29.99 |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | -- |
| METAR weather report | -- |
| Event Highest Injury | Minor |
| On Ground, Fatal Injuries | -- |
| On Ground, Minor Injuries | -- |
| On Ground, Serious Injuries | -- |
| Injury Total Fatal | -- |
| Injury Total Minor | 1 |
| Injury Total None | 1 |
| Injury Total Serious | -- |
| Injury Total All | 1 |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 17569 |
| NTSB Notification Source | NERCC |
| NTSB Notification Date | Apr 29 2004 12:00AM |
| NTSB Notification Time | 947 |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | Apr 28 2005 2:59PM |
| User who most recently changed record | NTSB\JOHB |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | Boston |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N3243P |
| NTSB Number | IAD04LA018 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | None |
| Flight plan Was Activated? | No |
| Damage | Substantial |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Beech |
| Aircraft Model | A36 |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | E-2943 |
| Certified Max Gross Weight | 3650 |
| Aircraft Category | Airplane |
| 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 | 6 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Retractable |
| Aircraft, Type of Last Inspection | Annual |
| Date of Last Inspection | Apr 26 2004 12:00AM |
| Airframe hours since last inspection | 2 |
| Airframe Hours | 1550 |
| ELT Installed | Yes |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | Harwil Avaition, Inc. |
| Aircraft Owner Street Address | 108 East Water Street |
| Aircraft Owner City | Dover |
| Aircraft Owner State | DE |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 19901 |
| Operator is an individual? | No |
| Operator Name | Hager S. Harrison |
| Operator Same as Owner? | No |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | No |
| Operator Street Address | -- |
| Operator City | Greenwich |
| Operator State | CT |
| Operator Country | USA |
| Operator Zip code | 06830 |
| 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) | Personal |
| Second Pilot on Board | No |
| Departure Point Same as Event | Yes |
| Departure Airport Code | BED |
| Departure City | Bedford |
| Departure State | MA |
| Departure Country | USA |
| Departure Time | 1503 |
| 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 | Takeoff - initial climb |
| Report sent to ICAO? | No |
| Evacuation occurred | No |
| Date of most recent change to record | -- |
| User who most recently changed record | -- |
| Since inspection or accident | Time of Accident |
| Event Location Runway Number and Location | 29 |
| Runway Length | 7001 |
| Runway Width | 150 |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |