Bell 47G accident near Sand Springs, Oklahoma, February 23, 1987
On February 23, 1987 at about 7:45 pm local time, a Bell 47G (helicopter), registered N6330D, was substantially damaged in an accident near Sand Springs, Oklahoma. It was an instructional flight under general aviation rules (Part 91). No one was hurt; 2 people were on board or involved. The weather was visual conditions (good weather).
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
- February 23, 1987 · about 7:45 pm local time
- Place
- Sand Springs, Oklahoma · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Bell 47G · all 47Gs on the register
- Registration
- N6330D · registry record · serial 1044
- Damage
- Substantial damage
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
INSTRUCTOR PLT WAS DEMONSTRATING A CONFINED AREA TAKEOFF TO THE PVT PLT TAKING ADVANCE INSTRUCTION. AS THE ACFT CLEARED THE BARRIERS, THE QUARTERING HEAD WIND SHIFTED TO A TAIL WIND AND THE ACFT LOST TRANSLATIONAL LIFT. APPLICATION OF FULL POWER DID NOT REMEDY THE SITUATION AND THE ACFT LOST ROTOR RPM. ACFT SETTLED INTO THE TREES BEFORE THE INSTRUCTOR COULD REESTABLISH A CLIMB. A TAIL WIND WOULD SUBSTANTIALLY INCREASE THE POWER REQUIREMENT FOR THE MANEUVER THAT WAS BEING ATTEMPTED.
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: flight instructor, commercial pilot
- Ratings: single-engine land; instructor: airplane single-engine; instructor: helicopter; instrument: airplane; instrument: helicopter; rotorcraft: helicopter
- Flight time: 5,099 hours in all; 237 in this make and model; 86 in the last 90 days; 4,725 as pilot in command
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 6,480 hours
- Last inspection: annual inspection, August 12, 1986; 172 hours since
- Maximum gross weight: 2,450 lb
- Seats: 2
- Landing gear: retractable
- Engine: Franklin 6VS-335 SER (piston); 0 hours total
- Operator: Allied Helicopter Services,Inc
The flight
- Departed from: 5F2 Tulsa OK at 7:30 pm
- Flight plan: none
- Runway 0
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 170° at 13 knots
- Visibility: 15 statute miles
- Sky: scat at 3,000 ft
- Temperature: 55°F (13°C), dew point 30°F (-1°C)
- Altimeter: 30.00 inHg
- Observation at 7:52 pm from TUL, 15 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 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.
Other NTSB records under N6330D the same tail number, which may have belonged to a different aircraft at the time
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.