Accident Details
Probable Cause and Findings
The loss of helicopter control due to a loss of hydraulic boost to the tail rotor pedal controls at takeoff, followed by a loss of hydraulic boost to the main rotor controls after takeoff. The reason for the loss of hydraulic boost to the main and tail rotor controls could not be determined because of fire damage to hydraulic system components and the lack of a flight recording device.
Aircraft Information
Registered Owner (Historical)
Analysis
***This report was modified on November 24, 2015, and September 6, 2016. Please the docket for this accident to view the original report.***
HISTORY OF FLIGHT
On March 18, 2014, about 0738 Pacific daylight time (PDT), an Airbus Helicopters (formerly Eurocopter) AS 350 B2, N250FB, was destroyed when it impacted terrain following takeoff from the KOMO TV Heliport (WN16), Seattle, Washington. The helicopter was registered to, and operated by, Helicopters Incorporated, Cahokia, Illinois, under the provisions of Title 14 Code of Federal Regulations Part 91. The commercial pilot and one passenger were fatally injured, and one person, located in a stationary vehicle, was seriously injured. Visual meteorological conditions prevailed, and no flight plan was filed for the local repositioning flight, which was originating at the time of the accident. The pilot's intended destination was the Renton Municipal Airport (RNT), Renton, Washington.
The Electronic News Gathering (ENG) equipped helicopter had landed on the KOMO News helipad about 30 minutes prior to the accident. The purpose was to refuel for its repositioning flight to RNT. A witness who was located on the south side of the helipad reported that he observed the helicopter initially lift off of the helipad to about 15 ft, followed by a muffled sound like a car backfiring. The witness opined that after lifting off it immediately pointed nose up, and began rotating counter-clockwise, after which it rotated out of sight. A second witness, who was stationed in a crane a few hundred feet to the northeast of the helipad, reported that he observed the helicopter lift up off of the helipad, turn toward the west, and then shot straight back with its nose up, and out of control. It then nosed down into the street below. The helicopter descended into an occupied automobile near a main street intersection, after which a postimpact fire ensured.
During the investigation, a review of three security camera recordings, which were provided to the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) by the Seattle Police Department, revealed that the helicopter initially landed on the helipad, and remained stationary for about 15 minutes. The helicopter lifted off and simultaneously began to rotate counter-clockwise in a near level attitude. The helicopter continued to rotate counter-clockwise for about 180 degrees while it ascended slightly above the elevated helipad, after which it began to ascend further while moving slightly away from the elevated helipad. After the helicopter completed about a 360-degree rotation, the helicopter transitioned to a nose-low (tail-high) attitude while it continued to rotate counter-clockwise. The helicopter rotated counter-clockwise another 180 degrees, and then began to lose altitude while moving rapidly away from the elevated helipad. The helicopter then descended until ground impact.
Examination of the accident site revealed that the helicopter came to rest on its right side, oriented on a magnetic heading of about 050 degrees. A vehicle located east of the main wreckage was fire damaged. Another vehicle, which was located immediately west of the main wreckage and oriented on a southerly heading, exhibited impact damage. All major structural components of the helicopter were located in the immediate area of the main wreckage. Wreckage debris was located within an approximate 340 foot radius to the main wreckage.
The helicopter was recovered to a secured location for further examination.
PERSONNEL INFORMATION
Pilot in Command
General
The pilot, age 59, possessed a commercial pilot certificate with a helicopter instrument rating. He also held a helicopter flight instructor certificate with an instrument helicopter rating. His most recent second-class medical certificate was issued on February 6, 2014, with the limitation, "Must wear corrective lenses and possess glasses for near and intermediate vision." The pilot successfully completed his most recent flight review in the accident helicopter on February 8, 2014.
A review of the pilot's personal pilot logbooks revealed that as of February 7, 2014, he had accumulated a total flight time of 6,538.8 hours, all in rotorcraft-helicopters. Additionally, the pilot had accumulated 6,295.5 hours as pilot-in-command, 2,841 hours of instruction given, 1,047 hours in the Airbus AS350-D, and about 5.5 hours in the Airbus AS350-B2 helicopter. Additionally, the pilot had logged 1,122 hours in the Bell 206 helicopter, and a total of 1,092 hours flight time in the Bell 407.
A family member revealed during an interview with NTSB investigators that the pilot worked part time as an ENG pilot on the early morning shift. He would normally awaken between 0300 and 0400, and report for work at 0500, normally Monday thru Friday, but sometimes on weekends if there was a need. He would normally return home from his full time job as an engineer for a local airplane manufacturing company, and predictably go to bed at 2000. The family member said that the pilot was in excellent health, had no sleep disorders, and had performed this schedule for many years. Additionally, the family member opined that the pilot was looking forward to flying full time after retiring from his full time job.
Pilot's ENG Operational Experience
A further review of the pilot's recorded personal logbook entries revealed that he had started ENG flight operations in a Bell 206 on May 30, 2002, accumulating a total of 1,090 hours in this make and model helicopter, prior to transitioning to the Airbus AS350-D model on August 16, 2004. The pilot then operated this make and model helicopter in ENG operations until July 9, 2008, having accumulated a total time of 1,047 hours in the AS350-D.
Prior to concluding ENG flight operations in the AS350-D during July 2008, the pilot received Bell 407 transition training with Bell Helicopters on April 26, 2006. The pilot then flew the Bell 407 on a limited basis from August, 2006 to January 2008, accumulating a total of about 24 hours of flight time during this period. On January 21, 2008, the pilot attended Bell 407 recurrent training, having received 2.5 hours of flight training. The pilot subsequently began flying the Bell 407 helicopter in ENG flight operations on March 24, 2008, with his last flight logged in this make and model helicopter on February 7, 2014. At this time, the pilot had accumulated a total flight time of 1,092 hours in the Bell 407.
Pilot's Airbus AS350 B2 Training
According to Helicopters Incorporated personnel, the accident helicopter arrived at the company's Renton base of operations on January 30, 2014. The helicopter had been ferried from St. Louis, Missouri, to Renton by a part time company Check Airman, and the Renton based pilot who shared flying duties with the accident pilot; this pilot normally flew the afternoon shift, relieving the accident pilot about 1000.
According to training records supplied to the NTSB IIC at the request of Helicopters Incorporated, the pilot began Airbus AS350-B2 training January 31, the day after the helicopter arrived at the Renton base. At this time the Check Airman gave the pilot 0.5 hours of recurrent training. Subsequently, on February 8, the accident pilot received an additional 3.0 hours of flight instruction, which was inclusive of a check ride. The pilot satisfactorily passed the check ride, as well as the Airbus AS350 limitations written test. The pilot next flew the accident helicopter on the day of the accident, March 18, which would have been 39 days after his most recent flight in the helicopter.
Airbus AS350 B2 Checklists Used During Training
During the postaccident examination of the helicopter, inclusive of the onsite and follow-up layout examinations, the helicopter's checklist was not observed. In several discussions with the Helicopters Incorporated Assistant Director of Operations and the company's Director of Safety, it was frequently stated that the Abbreviated Checklist for the AS350 BA/B2, Revision 1 (an internal document), dated June 30, 2009, which was a two-sided laminated checklist with a Federal Aviation Administration (FAA) Approved Date of August 20, 2009, and signed by an FAA inspector assigned to the St. Louis (STL) Missouri Flight Standards District Office, had been delivered with the helicopter when it arrived at the Renton base. Additionally, the Renton-based pilot (who had ferried the helicopter from St. Louis to Renton with the part-time company Check Airman, when interviewed by the NTSB IIC and asked which checklist would have been in the helicopter at the time of the accident), revealed that it was a two-sided, laminated checklist, and that it had an FAA approved stamp on it.
At the time of the accident, the most current revision to the AS350-B2 Rotorcraft Flight Manual (RFM) was Revision 4, dated the 11th week of year 2010. Revision 3, dated the 21st week of year 2006, contained changes to Paragraph 3 ("Starting") of Section 4.1 ("Operating Procedures") to set the fuel flow control lever (FFCL) to a position between the "OFF" and "FLIGHT" detents in order to achieve a gas generator speed (Ng) of between 67-70% before performing the hydraulic system checks. According to the airframe manufacturer, an Ng of 67-70% will result in a corresponding main rotor speed (Nr) of about 270 rotations per minute (RPM). According to the RFM, 100% Nr on the ground at low pitch is between 375-385 RPM. The previous procedure (Revision 2 and prior) was to set the FFCL to the "FLIGHT" detent, about 82% Ng, resulting in 100% Nr, prior to performing the hydraulic system checks. According to the airframe manufacturer, the change to the starting procedures in the RFM was a result of several events where the helicopter became unintentionally airborne due to the collective stick becoming unlocked during the hydraulic system checks. By performing the hydraulic system checks at 67-70% Ng, the helicopte...
Data Source
Data provided by the National Transportation Safety Board (NTSB). For more information on this event, visit the NTSB Records Search website. NTSB# WPR14FA137