Eurocopter COLIBRI EC120B accident near Springtown, Texas, February 26, 1999
On February 26, 1999 at about 3:10 pm local time, a Eurocopter COLIBRI EC120B (helicopter), registered N122TH, was substantially damaged in an accident near Springtown, Texas. It was a business flight under general aviation rules (Part 91). 1 person had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The improper touchdown executed by the pilot. Factors were the tail wind condition, and the manufacturer's inadequate design of the P3 pipe supports, which resulted in a fatigue fracture of the P3 pipe.
Source: NTSB aviation accident database, copy made October 4, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- February 26, 1999 · about 3:10 pm local time
- Place
- Springtown, Texas · map
- Type
- Accident
- Injuries
- 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Eurocopter COLIBRI EC120B COLIBRI EC
- Registration
- N122TH · registry record · serial 1017
- Damage
- Substantial damage
- Flight
- Business flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
While at cruise altitude, the helicopter's engine began to surge. The pilot initiated an autorotation to an open field. During the downwind forced landing, the skids dug into the ground, and the helicopter nosed over and came to rest on its left side. An examination of the engine revealed that the P3 air pipe, which supplies air to the fuel control, was broken close to the fitting on the combustion chamber casing. Examination of the P3 pipe revealed that its fracture was 'consecutive to the propagation of a fatigue fissure,' as a result of the pipe being 'subjected to an excessive vibratory excitation.' Engine vibration tests were conducted and two main excitation sources were identified. The two sources were the starter-generator and the breather gear assembly. The proposed solution to correct for this vibration consists of fitting an attachment clamp at mid-length of the P3 pipe, 'which moves the natural frequencies out of engine power ratings.'
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, private
- Ratings: single-engine land; instructor: helicopter; instructor: instrument helicopter; instrument: airplane; instrument: helicopter; rotorcraft: helicopter
- Flight time: 6,000 hours in all; 20 in this make and model; 80 in the last 90 days; 50 in the last 30 days; 5,000 as pilot in command; 2,000 on instruments
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 22 hours
- Last inspection: annual inspection, February 20, 1999; 14 hours since
- Maximum gross weight: 3,700 lb
- Seats: 5
- Landing gear: fixed
- Engine: Turbomeca ARRIUS 2F (turboshaft); 0 hours total
The flight
- Departed from: GPM Grand Prairie TX at 2:45 pm
- Destination: TDW Amarillo TX
- Flight plan: VFR
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 180° at 11 knots
- Visibility: 5 statute miles
- Sky: broken clouds at 2,200 ft; scat at 1,200 ft
- Temperature: 66°F (19°C), dew point 64°F (18°C)
- Altimeter: 29.00 inHg
- Observation at 3:53 pm from AFW, 19 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 |
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.
About this page
Everything above comes from the NTSB's public accident database: the narrative, probable cause and findings are the NTSB's own words, and the coded tables behind its report (pilot, aircraft, flight, weather, injuries, sequence of events) are written out in plain English. Pilots' ages, home towns and medical details are left out on purpose. The documents and photographs are the NTSB's docket, the folder of records gathered during the investigation, shown as the NTSB released them (the NTSB redacts some personal details first) and listed under the NTSB's own titles. This site's own text never names pilots, passengers or anyone else involved. A preliminary report describes what is known soon after the event and can change; the final report, with the probable cause, usually follows one to two years later and this page is refreshed when it does. Case number FTW99LA085.