Bell L4 EXPERIMENTAL accident near Arlington, Texas, August 24, 1991
On August 24, 1991 at about 12:59 pm local time, a Bell L4 EXPERIMENTAL (helicopter), registered N2770X, was substantially damaged in an accident near Arlington, Texas (Arlington airport). It was an other work-use 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 PILOT'S FAILURE TO MAINTAIN ADEQUATE ROTOR RPM DURING THE PLANNED AUTOROTATION AND HIS IMPROPER TOUCHDOWN.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 24, 1991 · about 12:59 pm local time
- Place
- Arlington, Texas · Arlington · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Bell L4 EXPERIMENTAL L4 EXPERIM
- Registration
- N2770X · no longer on the register · serial 51022
- Damage
- Substantial damage
- Flight
- Other work-use flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THE FLIGHT TEST PILOT WAS CONDUCTING HEIGHT/VELOCITY MANEUVERS ON THE MANUFACTURERS NEW HELICOPTER. A PLANNED AUTOROTATION WAS INITIATED TO THE RUNWAY. A HARD LANDING OCCURRED, AND A MAIN ROTORBLADE CONTACTED THE TAILBOOM, SEVERING IT. AN EYEWITNESS STATED THE HELICOPTER TOUCHED DOWN ON THE REAR SKIDS AND BOUNCED SEVERAL TIMES BEFORE THE TAILBOOM SEPARATED. NO MECHANICAL FAILURE WAS REPORTED BY THE PILOT.
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, flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; instructor: helicopter; instrument: airplane; instrument: helicopter; rotorcraft: helicopter
- Flight time: 11,400 hours in all; 2,138 in this make and model; 8,513 as pilot in command; 2,990 on instruments
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: rgt
The aircraft
- Airframe total time: 3,541 hours
- Last inspection: inspection type not recorded, January 2, 2000
- Maximum gross weight: 4,540 lb
- Seats: 2
- Landing gear: fixed
- Engine: Allison 250C30P (turboshaft); 0 hours total
- Operator: Bell Helicopter Textron, INC.
The flight
- Departed from: 0 at 12:30 pm
- Runway 34, 4,000 ft by 100 ft
Weather at the time
- Light: daylight
- Visibility: 10 statute miles
- Temperature: 75°F (24°C), dew point 70°F (21°C)
- Altimeter: 30.00 inHg
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 N2770X 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.