Sikorsky S-76B accident near Sutton, Massachusetts, June 6, 1986
On June 6, 1986 at about 1:00 pm local time, a Sikorsky S-76B (helicopter), registered N5AZ, was destroyed in an accident near Sutton, Massachusetts. It was a business flight under general aviation rules (Part 91). 4 people were killed. The weather was instrument conditions (cloud, fog or low visibility).
The NTSB's probable cause their words, unchanged
The NTSB has not yet published a probable cause for this accident. Investigations usually take one to two years; this page updates when the final report is released.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- June 6, 1986 · about 1:00 pm local time
- Place
- Sutton, Massachusetts
- Type
- Accident
- Injuries
- 4 people were killed.
- Weather
- instrument conditions (cloud, fog or low visibility)
- Aircraft
- Sikorsky S-76B · all S-76Bs on the register
- Registration
- N5AZ · registry record · serial 760313
- Damage
- Destroyed
- Flight
- Business flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
ABOUT 16 MIN AFTER TAKEOFF, WHILE CRUISING AT 6000' MSL IN IMC, THE PLT TRANSMITTED 'SIKORSKY 507' (CALL SIGN OF ACFT HEFREQUENTLY FLEW). THE ATC CTLR WAS TALKING TO ANOTHER FLT & DID NOT RESPOND. ABOUT 1 MIN LATER, RDO & RADAR CONTACT WERELOST & THE HELICOPTER CRASHED WHILE IN A STEEP/HI SPD DSCNT. AN INV SHOWED THAT DRG IMPACT, IT WAS IN A 10 DEG NOSE UP, 12 DEG RGT BANK ATTITUDE. WITNESSES, WHO HEARD THE HELICOPTER, RPRTD THE ENGS WERE RUNNING AT HI PWR BFR IMPACT. THEY DESCRIBED THE WX AS LOW OVERCAST WITH RAIN, FOG & POOR VIS. RADAR DATA SHOWED THAT JUST BFR ENTERING A DSCNT, THE HELI- COPTER WAS ON A SW HDG AT 138 KTS, WHEN ITS HDG & SPD BGN TO VARY. IT SLOWED TO 116 KTS, TURNED LEFT TO 229 DEG, THEN ENTERED A RGT DSCNDG SPIRAL & CRASHED. NO PREIMPACT PART FAILURE/MALFUNCTION WAS FND. PREV DISCREPANCIES NOTED OF N5AZ'SELEC FLT INSTRUMENT SYS (EFIS) ON 5/5/86 & 5/27/86; CAUSE OF 1ST WAS NOT FND; 2ND WAS RELATED TO A POPPED CKT BRKR. NO KNOWN EFIS PRBLM ON ACDNT FLT, BUT ACFT WAS BADLY DMGD. PLT HAD 1525 HRS IN S-76A, ONLY 30 HRS IN S-76B (WITH EFIS).
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: airline transport pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane multi-engine; instructor: airplane single-engine; instructor: helicopter; instrument: airplane; instrument: helicopter; rotorcraft: helicopter
- Flight time: 1,555 in this make and model; 98 in the last 90 days
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: unk
The aircraft
- Airframe total time: 107 hours
- Last inspection: approved inspection programme, May 30, 1986; 7 hours since
- Maximum gross weight: 11,400 lb
- Seats: 7
- Landing gear: retractable
- Engine: P&W PT6B-36 (turboshaft); 0 hours total
- Fire on the ground
- Operator: United Technologies
The flight
- Departed from: BED Bedford MA at 12:43 pm
- Destination: JSD Stratford CT
- Flight plan: IFR
- Runway 0
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 060° at 6 knots
- Sky: not recorded
- Temperature: 61°F (16°C), dew point 57°F (14°C)
- Altimeter: 30.00 inHg
- Observation at 1:57 pm from ORH
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.