Eurocopter AS-350-B accident near Cambridge, Massachusetts, February 22, 1995
On February 22, 1995 at about 2:37 pm local time, a Eurocopter AS-350-B (helicopter), registered N20SP, was destroyed in an accident near Cambridge, Massachusetts. It was a public-use flight under general aviation rules (Part 91). 4 people were killed. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
1) THE MASSACHUSETTS STATE POLICE (MSP) MANAGEMENT'S FAILURE TO PROVIDE ADEQUATE OVERSIGHT OF ITS AIR WING; 2) FUEL CONTAMINATION AND OBSTRUCTED FUEL INJECTOR NOZZLES, DUE TO INADEQUATE FUEL STORAGE AND STORAGE REQUIREMENTS BY THE MSP, RESULTING IN A LOSS OF ENGINE POWER; AND 3) THE FAILURE OF THE PILOT TO EXECUTE A PROPER AUTOROTATION, WHICH RESULTED IN A LOSS OF ROTOR RPM AND SUBSEQUENT LOSS OF HELICOPTER CONTROL.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- February 22, 1995 · about 2:37 pm local time
- Place
- Cambridge, Massachusetts
- Type
- Accident
- Injuries
- 4 people were killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Eurocopter AS-350-B · all AS-350-Bs on the register
- Registration
- N20SP · registry record · serial 1915
- Damage
- Destroyed
- Flight
- Public-use flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
A MASSACHUSETTS STATE POLICE (MSP) HELICOPTER DEPARTED A HELIPORT WITH TWO CREWMEMBERS & TWO PASSENGERS, & CLIMBED TO ABOUT 600' OVER A RIVER. WITNESSES REPORTED SEEING A PUFF OF "SMOKE" (OR VAPOR) FROM THE ENGINE EXHAUST. THE HELICOPTER WAS OBSERVED TO TURN TOWARD THE RIVER BANK & DESCEND AT AN ANGLE BETWEEN 45 & 70 DEGREES. WITNESSES STATED THAT THE MAIN ROTOR BLADES WERE EITHER TURNING SLOWLY OR HAD STOPPED PRIOR TO THE HELICOPTER COLLIDING WITH A BOAT HOUSE ROOF. NO PREIMPACT FAILURE OF THE MAIN ROTOR OR TRANSMISSION WAS FOUND. EXAMINATION OF THE ENGINE REVEALED THAT FIVE OF THE SIX FUEL INJECTION PORTS WERE CLOGGED. SAMPLES FROM THE HELICOPTER FUEL SYSTEM CONTAINED IRON OXIDE & WATER. THE MSP HAD A 6,000 GALLON IN-GROUND FUEL STORAGE TANK THAT HAD NOT BEEN MAINTAINED OR SECURED IN 14 YEARS (EXCEPT FOR A FILTER CHANGE BETWEEN 1984 AND 1986). FUEL SAMPLES FROM THE STORAGE TANK CONTAINED HIGH LEVELS OF RUST & WATER, AS WELL AS DEGRADED THERMAL PROPERTIES. FURTHER INVESTIGATION REVEALED THAT THERE WAS A LACK OF OVERSIGHT IN THE MSP AIR OPERATIONS & NO TRAINING, SAFETY, OR FUEL MANAGEMENT PROGRAM. RECORDS SHOWED THAT IN THE PAST FIVE YEARS, THE MSP PROVIDED THE PILOT WITH ONLY ONE TRAINING SESSION THAT CONSISTED OF A TW0 DAY GROUND SCHOOL & ONE FORMAL TRAINING FLIGHT.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
Pilot
- Certificate: commercial pilot, private
- Ratings: single-engine land; rotorcraft: helicopter
- Flight time: 1,150 hours in all; 900 in this make and model; 20 in the last 90 days; 13 in the last 30 days
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 2,870 hours
- Last inspection: approved inspection programme, February 13, 1995; 20 hours since
- Maximum gross weight: 4,300 lb
- Seats: 6
- Landing gear: fixed
- Engine: Turbomeca ARRIEL 1B (turboshaft); 0 hours total
The flight
- Departed from: MA89 Boston MA at 2:35 pm
- Destination: Framingham MA
- Flight plan: none
- Runway 0
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 360° at 7 knots
- Visibility: 12 statute miles
- Sky: overcast at 3,300 ft; scat at 2,700 ft
- Temperature: 88°F (31°C), dew point 70°F (21°C)
- Altimeter: 30.00 inHg
- Observation at 2:54 pm from BOS, 5 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 2 | |||
| Passengers | 2 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.