DFW06LA118

NTSB accident investigation · Eurocopter EC120B · Intracoastal, LA · May 5, 2006

Accident · Minor injuriesLimited investigationFinal report
Date
May 5, 2006, 07:30 local (12:30 UTC)
Place
Intracoastal, LA
Coordinates
28.9775, -91.4697
Injuries
1 minor
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N514ALEurocopter EC120B
Weather
Visual (VMC) · Day
Status
Completed · report March 31, 2008
Report
Approved by Office Director
Parties
Baton Rouge
FAA report
20060505010039A
Case key
63628

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 loss of control for undetermined reasons.

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.

Loss of control - in flightClimb
Reason for occurrence undeterminedCause
In flight collision with terrain/waterDescent - uncontrolled
Terrain condition - water

Analysis

The pilot reported that prior to bringing the helicopter to a hover, he ran the engine to 100 percent, brought the helicopter to a hover, and proceeded to hover to the center of the helideck for a pre-takeoff check. All systems and controls were found to be operating normally. The pilot took off on a southeast heading and established a climb at a rate of 500 feet per minute. Somewhere between 300 and 400 feet, the pilot initiated a left turn to a northerly heading. At that time the pilot experienced an uncommanded cyclic movement to the right-forward quadrant and the collective started to come up (increase). The pilot added that the nose of the helicopter pitched-up and the helicopter started to roll to the left. The pilot stated that he concluded that he had experienced "a hydraulic failure of some kind," so as per the emergency procedures, he turned the hydraulic control switch on the collective lever to the "off" position. The pilot added that the hydraulic light on the console was activated indicating that the hydraulics were "off." The action taken by the pilot were not effective and the pilot was not able to regain control of the helicopter. The helicopter continued rolling to the left and entered a spin to the left while the helicopter remained in a nose low attitude. The pilot stated that the helicopter spun for about 3 to 5 revolutions and impacted the water between a 70 and a 90 degree nose down attitude. The pilot recalled that about the second spin, he initiated a "mayday" call. The pilot added that the helicopter impacted the water hard. After impacting the water, the helicopter rolled inverted, but continued to float. Prior to exiting, the pilot reported that he discharged the helicopter's float inflation bottle. The 3 main rotor servos, part number SC 5091-1 (serial numbers 877, 1393, and 533) and the Hydraulic Power Pack were examined at the Goodrich-SAMM facilities in France, under the control and supervision of the BEA. All 3 servocontrols were found to be in good conditions and performed within limits. The Hydraulic Power Pack was found to have extensive impact damage and the hydraulic pump had separated from the power back, and was missing. The actuators and the hydraulic system showed no anomalies and performed within the limits for the manufacturers' specification. The investigation concluded that the control system was installed and properly connected prior to the helicopter impact with the water. No defects or anomalies were found during the examinations that could have prevented normal operation. Additionally, all of the rotating components for the drive-train of the helicopter (main rotor blades, the rotor hub, the swatchplate, the scissors drive, the free wheel, the main gear box (transmission),etc.,) underwent a detailed examination at the manufacturer's facility in Marignane, France, under the supervision of the BEA. The examination concluded that all of the observed damage and fractures were due to overload. The investigation was inconclusive and was unable to find any pre-existing defects. The investigation concluded that the control system was properly installed and connected prior to the helicopter impact with the water. No defects or anomalies were found during the examinations that could have prevented normal operation. The reason for the loss of control could not be determined.

Factual narrative

"This case was modified July 10, 2008."

On May 5, 2006, approximately 0730 central daylight time (CDT), a single-engine Eurocopter EC120B helicopter, N514AL, registered to and operated by Air Logistics LLC, of New Iberia, Louisiana, was substantially damaged upon impact with the water following a loss of control during initial takeoff climb during takeoff from offshore platform Eugene Island (EI) 120, located in the Gulf of Mexico. The airline transport rated pilot, sole occupant of the helicopter, sustained minor injuries. Visual meteorological conditions prevailed, and a company flight plan was filed for the 14 Code of Federal Regulations (CFR) Part 135 positioning flight. The flight originated from EI 120 approximately 0715, and was destined for EI 105.

The 22,706-hour pilot was interviewed following the accident. The pilot reported that he awoke at 0430 in the morning, got dressed, and carried all of his flight equipment to the helicopter at the platform and proceeded to perform the preflight checks of the helicopter. He added that he sumped the helicopter's fuel system, untied the tie downs, leaving one main rotor blade tied down. The pilot reported that he did not find any discrepancies during the preflight check and then proceeded downstairs to have breakfast and attend the daily platform morning meeting at 0600.

The pilot reported that after being assigned the mission to fly to EI 120, EI 105, EI108, he returned to the helicopter, double-checked all the tie downs were removed and removed the remaining blade tie down. The pilot further stated that he climbed aboard the helicopter and completed the pre-start and engine start as per the checklist. All systems were checked and all systems were found to be operational. The pilot reported that prior to departure, he noted the helicopter had 350 pounds (50 gallons) of fuel on board for the flight, and the radio was set on the Eugene Island radio frequency (129.62).

The pilot reported that prior to bringing the helicopter to a hover, he ran the engine to 100%, brought the helicopter to a hover, and proceeded to hover to the center of the helideck for a pre-takeoff check. All systems and controls were found to be operating normally. The pilot took off on a southeast heading and established a climb at a rate of 500 feet per minute. Somewhere between 300 and 400 feet, the pilot initiated a left turn to a northerly heading. At that time the pilot experienced an uncommanded cyclic movement to the right-forward quadrant and the collective started to come up (increase). The pilot added that the nose of the helicopter pitched-up and the helicopter started to roll to the left.

The pilot stated that he concluded that he was experiencing "a hydraulic failure of some kind," so as per the emergency procedures; he turned the hydraulic control switch on the collective lever to the "off" position. The pilot added that the hydraulic light on the console was activated indicating that the hydraulics were "off." The actions taken by the pilot were not effective and the pilot was not able to regain control of the helicopter. The helicopter continued rolling to the left and entered a spin to the left while the helicopter remained in a nose low attitude. The pilot stated that the helicopter spun for about 3 to 5 revolutions and impacted the water between a 70 and a 90 degree nose-down attitude.

The pilot recalled that about the second spin, he initiated a "mayday" call. The pilot added that the helicopter impacted the water hard. After impacting the water, the helicopter rolled inverted, but continued to float. Prior to exiting, the pilot reported that he discharged the helicopter's float inflation bottle. A rescue boat picked-up the pilot within 5-minutes and he was taken to offshore platform EI 120CF (central facility) where the pilot was examined and received first aid.

There was one eye-witness to the mishap. The witness, a worker at the offshore platform, reported that he was standing on the platform and he observed that after takeoff, the helicopter dropped down pretty close to the sea, then began to rise again in an uncontrolled manner while turning. The witness statement says nothing about seeing whether the blades contacted water prior to impact. The witness stated he "heard the helicopter taking off and saw him drop down very close to the water. The helo then began to rise again in a very uncontrolled way while turning in a very unstable circle. Then the helo tail dropped and the helo turned to the right at the same time. I watched as the helo started to lose lift and start to come back down. I then ran to the P.A. and announced the chopper was going down. As soon as I reached the P.A. I heard him hit."

The wreckage was located at latitude 28 degrees 58.656 minutes North, longitude 91 degrees 28.190 minutes West, about 3/4 of a mile from offshore platform EI 120. The wreckage of the helicopter was retrieved from the water and placed onto offshore platform EI 108, before being transported to the Air Logistics' maintenance facilities in New Iberia, Louisiana.

The aircraft was a Eurocopter model EC120B, assigned serial number 1266, when it was manufactured in France in 2001. The helicopter was powered by a single Turbomeca Arrius 2F turbine engine, serial number 34282. A review of the maintenance records for the helicopter did not revealed any overdue inspections or discrepancies. The helicopter had accumulated a total of 2,728.2 hours at the time of the accident.

On May 8, 2006, an examination of the wreckage was conducted at the operator's maintenance facilities at New Iberia, Louisiana, by representatives from the Federal Aviation Administration, Air Logistics LLC, American Eurocopter LLC, and Turbomeca, under the supervision of an FAA inspector. A detailed examination of the wreckage revealed minimal impact deformation to the fuselage of the helicopter. The forward passenger sliding window was found broken and with portions of the broken window found inside the cockpit area. The damage to the airframe was consistent with the helicopter impacting the water at a 60 to 70 degrees nose low attitude, with low or no forward ground speed, at a very slow rate of descent.

Flight control continuity was established from the cyclic and collective lever to the non-rotating swash plate. Individual lateral, pitch, and collective inputs resulted in proper input to their respective main rotor servo bodies. The left lateral servo was found to be slightly loose from its mount; however, it was still connected at is input and output connections. The antitorque pedals were moved, and proper pitch change was transmitted to the fenestron blades.

A detailed examination of all three of the main rotor blades was conducted at this time. The rotor blades in the EC120B helicopter rotate in the clockwise direction in a yellow-blue-red sequence, with the yellow blade considered as the master blade. All three main rotor blades were found to have sustained impact damage. Only the root area for the red blade was recovered. Approximately 80% of the blue blade was recovered in three main sections, with the lower surface of the blade exhibiting compression damage. The yellow blade was recovered in two main sections. This blade was also found to exhibit compression damage to the bottom (lower) portion of the blade.

The tail rotor drive shaft was found torsionally separated adjacent to the intake, with the direction of separation consistent with a sudden stoppage of the main rotor system (forward of the separation). The tail rotor driveshaft assembly aft of the point of the torsional separation was intact. Rotation of that portion of the shaft resulted in the smooth rotation of the fenestron blades. The tail striker plate and keel were found separated from the lower fenestron fairing.

The four suspension bars for the main gear box (MGB) or main

Aircraft

Registration
N514AL
Reported as
Eurocopter EC120B
Category
Helicopter
Serial number
1266
Airframe hours
2,672
Engine
Turbomeca Arrius 2F, 322 horsepower, turbo shaft
Damage
Substantial damage
Flight
Part 135
Registered owner
Air Logistics LLC
Airworthiness certificate
Standard, Normal
Last inspection
AAIP · March 1, 2006 · 55.8 hours before
Departed
Intracoastal Ci, LA
Flight plan
Company VFR

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
67
Injuries
Minor
Certificate
Airline transport
Airplane ratings
Single-engine land
Medical
Class 2, Without waivers/limitations
Last flight review
November 1, 2005
Seat
Right
Flight hours
22,709 total · 1,409 in this make and model · 21,510 as pilot in command · 55 in the last 90 days · 4 in the last 30 days

Weather

Conditions
Visual (VMC) · Day
Wind
0° at 0 knots
Visibility
4 statute miles
Temperature
72 °F, dew point 70 °F
Altimeter
29.97 inHg
Observed at
LFT

Docket · 12

The files NTSB released with the investigation on March 17, 2008, on NTSB’s docket system: statements, records, photos and specialists’ reports. 17.4 MB 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.