Bell 407 accident near Mi 700, February 16, 2003
On February 16, 2003 at about 6:25 pm local time, a Bell 407 (helicopter), registered N407HH, was destroyed in an accident near Mi 700. It was flown under charter and air-taxi rules (Part 135). 2 people were killed and 3 people were seriously injured. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The catastrophic failure of the engine resulting from 1st stage turbine wheel blade failure due to type 1 hot corrosion (sulfidation). Contributing factors were the pilot's failure to brief the passengers on emergency safety equipment (life raft), the pilot's failure to deploy the skid-mounted emergency float system during the autorotation, the high wind conditions, and rough sea state.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- February 16, 2003 · about 6:25 pm local time
- Place
- Mi 700 · map
- Type
- Accident
- Injuries
- 2 people were killed and 3 people were seriously injured.
- Weather
- visual conditions (good weather)
- Aircraft
- Bell 407 · all 407s on the register
- Registration
- N407HH · registry record · serial 53460
- Damage
- Destroyed
- Flight
- Flight · charter and air-taxi rules (Part 135)
The NTSB's narrative final · quoted from the NTSB record
The helicopter, flown by 19,000-hour pilot and transporting 4 passengers to an offshore oil platform, experienced a catastrophic engine failure and autorotated into open ocean water in the Gulf Of Mexico. Within a few seconds after landing on the water, the helicopter rolled inverted, the pilot and passengers exited, inflated their personal life vests, and waited for rescue. The pilot and one of the passengers drowned prior to rescue personnel arriving about 2 hours after the accident. Surviving passenger statements indicated that they were not aware of an emergency lift raft on-board the helicopter, and that the skid-mounted emergency float system was not inflated prior to landing. Rescue personnel reported high wind and rough seas in the area of the accident. Examination of the wreckage revealed that the float "ARM" switch was found in the disarmed position and its cover closed. The skid-mounted emergency floats were found inside their protective bags. The float system tested functional, and no anomalies were found during airframe component examinations. Download data from the ECU showed that engine performance prior to the loss of power was normal and the engine was operating in a steady state condition prior to the initial deterioration of NG. Detailed inspection of the engine revealed progressive turbine wheel damage throughout the power turbine. The damage varied from approximately 95% of the airfoil material missing on the 1st stage wheel to approximately 10% of the material missing on the 4th stage wheel. The damage observed in the gas producer turbine section was consistent with the separation of one or more of the first stage wheel airfoils. Mostly all of the fracture surfaces were obscured, typical of elevated turbine temperatures (according to the manufacturer, in excess of turbine and material limits). All 4 turbine wheels had evidence of solutioning and incipient melting was observed at the tips of the airfoil remnants. Fracture surfaces of the 1st stage wheel airfoils did not reveal the presence of fatigue. Detailed metallurgical examination revealed the presence of sulfides on the 1st and 2nd stage turbine wheel surfaces. According to the manufacturer, the presence of sulfides is evidence that sulfidation has occurred. Damage on the concave surface adjacent to the fractures near the leading edges of the airfoils was found consistent with type 1 hot corrosion (sulfidation) damage. Examination of radial cracks at the trailing edges of the airfoils revealed heavy oxidation consistent with thermal fatigue. According to Rolls Royce, that "thermal fatigue cracking at the airfoil base is not uncommon." Evidence of EPS 10649 (S1 Aluminide, which is a protective coating applied to the turbine wheel during manufacturing), was confirmed adjacent to the corrosive damage found on the wheels.
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: instructor: helicopter; rotorcraft: helicopter
- Flight time: 19,339 hours in all; 151 in this make and model; 57 in the last 90 days; 21 in the last 30 days
- Last flight review: May 31, 2004
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: rgt
- Injury: fatal
The aircraft
- Airframe total time: 546.8 hours
- Last inspection: approved inspection programme, December 10, 2002; 62.2 hours since
- Maximum gross weight: 6,000 lb
- Seats: 7
- Landing gear: fixed
- Engine: Allison 250-C47B (turboshaft); 0 hours total
The flight
- Departed from: Ingleside TX at 6:10 pm
- Destination: Mi 700 GM
Weather at the time
- Wind: from 360° at 20 knots, gusting 30
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 50°F (10°C), dew point 0°F (-18°C)
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 1 | 3 |
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.