FTW02LA200

NTSB accident investigation · Bell 206L3 · Gulf of Mexico · June 29, 2002

Accident · No injuriesLimited investigationFinal report
Date
June 29, 2002, 10:00 local (15:00 UTC)
Place
Gulf of Mexico
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Standing
Aircraft
N255EVBell 206L3
Weather
Visual (VMC) · Day
Status
Completed · report September 30, 2003
Report
Approved by Office Director
Parties
FAA FSDO
FAA report
20020629013969A
Case key
55131

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

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Probable cause

The pilot's failure to maintain proper rotor RPM during engine shutdown due to high wind conditions, which resulted in the main rotor blades contacting the tailboom. A contributing factor was the gusty wind conditions.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

On ground/water encounter with weatherStanding - idling rotors
Weather condition - high wind
Engine shutdown - attemptedPilot in command
Adequate rotor rpm - not maintainedPilot in commandCause
Weather condition - gustsFactor
Misc rotorcraft,tail boom - separation

Analysis

After landing on the offshore platform, the pilot positioned the helicopter into the prevailing headwind and initiated engine shutdown procedures. The pilot reported that the wind at this time was from the southeast at 15 to 20 knots, and the rain remained about 2 miles southeast of the platform. The pilot further stated that within seconds after shutting down the engine "the wind picked up to 50-60 knots, while the rain was still about 1-2 miles away." The pilot added that he applied the rotor brake after the rotor had slowed to 35-40 percent; however, the rotor brake did not appeared to have any effect in slowing down the rotor system. As the rotor system was buffeted by strong wind, the rotor system became unbalanced and eventually struck the tail boom approximately 2 feet forward of the tail rotor gear box.

Factual narrative

On June 29, 2002, at 1000 central daylight time, a Bell 206L3 helicopter, N255EV, was substantially damaged when the main rotor blades contacted and severed the tailboom while attempting to shutdown while on an off-shore platform in the Gulf of Mexico known as Brazos A-19B. The commercial pilot, sole occupant of the helicopter, was not injured. The helicopter was operated by Evergreen Helicopters International, Inc., an on-demand air taxi operator based at Galveston, Texas. The helicopter was owned by Evergreen Equity, Inc., of Mc. Minnville, Oregon. Visual meteorological conditions prevailed for the 14 Code of Federal Regulations Part 91 positioning flight for which a company VFR flight plan was filed. The positioning flight originated about 5 minutes prior to the accident from another nearby offshore platform known as Brazos A-19JD.

Upon completing his passenger drop-off mission at Brazos A-19 JD uneventfully, the pilot headed back to Brazos A-19B. The pilot reported that he was aware of the heavy rain and convective activity approaching the offshore platform from the southeast.

After landing at the helideck at the Brazos A-19B platform, which is located 200 feet off the surface of the ocean, the pilot positioned the helicopter into the prevailing headwind and initiated the engine shutdown procedures. The pilot reported that the wind at this time was from the southeast at 15 to 20 knots, and the rain showers remained about 2 miles southeast of the platform.

The pilot further stated that within seconds after shutting down the engine "the wind picked up to 50-60 knots, while the rain was still about 1-2 miles away." The pilot added that he applied the rotor brake after the rotor had slowed to 35-40 percent; however, the rotor brake did not appeared to have any effect in slowing down the rotor system. As the rotor system was buffeted by the strong wind, the rotor system became unbalanced and eventually struck the tailboom approximately 2 feet forward of the tail rotor gear box.

The operator reported that the effect of the microburst spun the helicopter about 15 feet to the left, fortunately towards the center of the platform. The pilot reported that he retrieved the helicopter tie-down straps and secured the helicopter to the helideck.

The FAA inspector, who traveled to the accident site, confirmed that the rotor brake system was fully operational and reported no anomalies with any aircraft system.

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Aircraft

Registration
N255EV
Reported as
Bell 206L3
Category
Helicopter
Serial number
895089
Airframe hours
9,773.8
Engine
Allison 250-C30, 650 horsepower, turbo shaft
Damage
Substantial damage
Flight
Positioning · Part 91
Operator
Evergreen Helicopters International Inc.
Registered owner
Evergreen Equity Inc.
Airworthiness certificate
Standard, Normal
Last inspection
100 hour · June 5, 2002 · 60 hours before
Departed
Gulf of Mexico, GM
Flight plan
Company VFR

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
26
Injuries
None
Certificate
Commercial
Airplane ratings
Multi-engine land, Single-engine land
Instrument ratings
Airplane
Medical
Class 2, Valid Medical--no waivers/lim.
Last flight review
July 12, 2001
Seat
Right
Flight hours
6,000 total · 1,000 in this make and model · 5,200 as pilot in command · 120 in the last 90 days · 60 in the last 30 days · 5 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
135° at 50 knots, gusting 60
Visibility
5 statute miles
Lowest ceiling
None
Temperature
88 °F, dew point 66 °F
Altimeter
30.01 inHg

Docket · 2

The files NTSB released with the investigation on July 29, 2003, on NTSB’s docket system: statements, records, photos and specialists’ reports. 358 KB in all.

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.