AS 350 B3 Training Mishap... October 2013

During training, regardless of the maneuvers carried out, it is always possible to de-activate the failure simulation by resetting the selector to "Auto." The automatic governor becomes immediately active provided that the twist grip has not been reduced beyond 30° ("Idle" switch activated). (ref. flight manual)

HISTORY OF FLIGHT

On October 29, 2013, at 1720 Hawaiian standard time, a Eurocopter France AS350/B3 helicopter, N985EW, was substantially damaged when it landed hard following a loss of main rotor rpm (NR) at Kona International Airport, Kailua Kona, Hawaii. The flight instructor received minor injuries, and the commercial pilot receiving instruction was not injured. The helicopter was being operated by Air Medical Resource Group under the provisions of 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed for the local instructional flight that began about 1659. A flight plan had not been filed for the flight.

The commercial pilot reported that the first planned maneuver of the flight was to practice manual throttle control with the Full Authority Digital Engine Control (FADEC)-governor disengaged. The helicopter was started and repositioned to a taxiway with the governor engaged. The instructor then moved the "AUTO[matic]/MAN[ual]" governor switch to "MAN" to disengage the governor. As expected, the red "GOV" light on the caution/warning panel illuminated. The commercial pilot found the twist grip throttle control "excessively stiff and difficult to rotate." He checked the throttle control friction wheel and determined that no friction was applied. This was the first time the commercial pilot had flown a Eurocopter helicopter in the manual mode, and he was unfamiliar with "how stiff the control was supposed to be." He said that the flight instructor assured him that it was normal and was purposely stiff to avoid over controlling.

The commercial pilot lifted the helicopter to a 3-foot hover and, by using the anti-torque pedals, executed two 360-degree stationary hovering turns, one to the right and one to the left. He stated that it "took a good bit of effort" to rotate the twist grip but he was able to manipulate it and maintain NR within normal limits. Next, he was asked by the instructor if he was ready to perform a left closed traffic pattern back to their departure point. He informed the instructor that he was ready, and the instructor told him to perform a normal takeoff using non-abrupt control inputs in order to maintain normal NR. The commercial pilot reported that the takeoff, transition into cruise flight on downwind leg, and initial descent were uneventful with NR within normal limits. While on final approach to land south on taxiway A, "at some point below 400 feet," the commercial pilot noticed that NR was decreasing. He rotated the twist grip to increase power, but the NR continued to decrease. Next, he heard the low NR audio warning, and he felt the instructor join him on the flight controls. The two pilots lowered the collective to enter an autorotation. The commercial pilot said that NR never recovered to the normal range even though the twist grip had been rotated to its maximum position.

The commercial pilot said that about 50 feet, he applied initial pitch (increased collective) to decrease the rate of descent but the NR was "quite low," and the rate of descent did not decrease. He adjusted the cyclic to level the helicopter before ground impact. Both pilots pulled up on the collective to cushion the landing, but there was insufficient NR remaining to slow the descent. The helicopter landed hard, slid forward on the taxiway, and yawed about 90 degrees to the left. The commercial pilot said that after the helicopter came to a stop, he made no attempt to shut down the engine or turn off electrical power before exiting the helicopter, and he had no knowledge as to "when or how the engine became shutdown."

The instructor reported that they were conducting maneuvers in manual governor mode and that the flight was uneventful until the helicopter was on short final about 200 to 300 feet above the ground. At that point, NR began to "decrease rapidly and at the same time [the commercial pilot] said the throttle was full open." The instructor stated that he took the controls and attempted to roll on more throttle but found that the throttle was already full open. He lowered the collective in an attempt to conserve NR and then attempted to cushion the landing (by raising the collective) and land as flat as possible with some ground run. He stated that the helicopter landed hard but stayed upright. When the helicopter came to a stop, "the engine was not running and [the main rotor] blades were coasting to a stop." The instructor applied the rotor brake and shut off the battery and engine switches before exiting the helicopter.

PERSONNEL INFORMATION

The flight instructor held a commercial pilot certificate with rotorcraft-helicopter and instrument-helicopter ratings. He had private pilot privileges in single-engine land airplanes. He held a flight instructor certificate with helicopter and instrument-helicopter ratings. He held a second-class medical certificate dated January 3, 2013, with the limitation that he possess glasses for near and intermediate vision. He was hired by Air Medical Resource Group on July 1, 2012. He had a total flight time of about 15,500 hours, of which about 15,000 hours were in rotorcraft and about 1,500 hours were in the accident make and model helicopter. He had given about 12,000 hours of flight instruction, of which about 1,000 hours were in the accident make and model helicopter.

The commercial pilot receiving instruction held a commercial pilot certificate with airplane single-engine land, airplane multi-engine land, rotorcraft-helicopter, and instrument-helicopter ratings. He also held a flight instructor certificate with airplane single-engine land, helicopter, instrument-airplane, and instrument-helicopter ratings. The pilot was issued a second-class medical certificate dated October 1, 2013, with no limitations. The pilot was hired by Air Medical Resource Group on October 23, 2013, and had accumulated a total flight time of about 5,760 hours, of which about 5,484 hours were in rotorcraft and about 6 hours were in the accident make and model helicopter.

AIRCRAFT INFORMATION

The helicopter was manufactured in 2000 and had accumulated about 2,634 hours at the time of the accident. It was powered by a Turbomeca Arriel 2B engine, which had a single-channel FADEC-type governor with a manual back-up in the form of a twist grip throttle control. The FADEC system included a digital computer or Digital Engine Control Unit (DECU), a pump/metering unit assembly or Hydro-Mechanical Unit (HMU), and electrical/mechanical links between the helicopter's controls, the DECU, and the HMU.

The twist grip throttle control had two ranges, one to reduce fuel flow and one to increase fuel flow, that were separated by a disengageable stop, referred to as the "VOL" or "FLIGHT" stop. The "FLIGHT" stop was installed on the right side collective only. When practicing FADEC-governor failure procedures (or in the case of an actual FADEC-governor failure), the stop is manually disengaged by the pilot, allowing the grip to be rotated through its full range of motion.

The AS350 B3 Flight Manual Supplement titled "Engine Failures Training Procedures" described the procedure for FADEC-governor failure training. The training procedure said that "in steady flight conditions," the pilot should set the governor switch to the "MAN" position and then follow the emergency procedure in the Flight Manual for a red "GOV" warning light.

The AS350 B3 Flight Manual listed the following pilot actions to be performed for a red "GOV" warning light:

· Check flight parameters

· Maintain NR in green range

· Unlock the FLIGHT detent (VOL), the fuel flow can be modified by turning the twist grip:

- to the left to increase fuel flow

- to the right to decrease fuel flow

· Only apply small amplitude adjustments, synchronized with the collective pitch control in order to maintain NR in the green range.

· Fly the approach at 40 [knots] and adjust the fuel flow rate to maintain NR within the upper section of the green range. Slowly reduce the speed[;] if necessary adjust the fuel flow rate slightly on the twist grip to maintain NR within the green range.

On final approach, when the collective pitch is increased on reaching hover, let the NR drop for touchdown, reduce the fuel flow rate before lowering the collective pitch.

With regard to returning from manual mode to automatic mode, the Flight Manual stated that the governor switch "can be replaced in the AUTO position irrespective of the NR value. Then return the twist grip to the FLIGHT detent (VOL)."

Eurocopter Information Notice No. 2169-I-67, "Rotor Flight Controls, Use of Twist Grip," dated June 15, 2010, included information about FADEC-governor failure training. Page 6 of the information notice stated, in part (emphasis in original):

Training for total governor failure must be carried out with an experienced instructor.


The training starts by simulating a total engine governor failure by setting the "Auto/Manu" selector to "Manu."

During training, regardless of the maneuvers carried out, it is always possible to de-activate the failure simulation by resetting the selector to "Auto." The automatic governor becomes immediately active provided that the twist grip has not been reduced beyond 30° ("Idle" switch activated).


The change to "Manu" mode freezes the fuel flow, lights up the red "GOV" light and activates the GONG (as for an actual total governor failure).

"Manu" mode shall be engaged only in stabilized flight conditions.


In "Manu" mode, the fuel flow is adjusted by the pilot using the twist grip. The pilot (on the RH side) must disengage the "Flight" stop of the grip. Relative to the frozen fuel flow, the pilot can then increase power by turning the grip in the increase range or reduce power by turning the grip in the reduction range.

The pilot must become accustomed to continuously coordinating movements with the collective pitch control lever and twist grip, hence the need to train regularly.

He must be accustomed to correctly coordinating actions in flight before carrying out a complete landing.

If the pilot does not feel sure of himself, he must not hesitate to return to "Auto" mode and then back to "Manu" mode from stabilized flight to perfect his pitch/grip coordination.

Flight control in "Manu" mode must be fully mastered before carrying out a complete landing.

According to the limitations section of the AS350 B3 Flight Manual, with power on, the range for NR on the ground at low pitch is 375 to 385 rpm, and the range for NR in stabilized flight is 385 to 394 rpm. With power off, the range for NR is 320 to 430 rpm. The low NR audio warning sounds below 360 rpm. The helicopter's rotor tachometer was marked with a green arc from 375 to 394 rpm indicating the normal operating range and two yellow arcs, one from 320 to 375 rpm and one from 394 to 430 rpm, indicating caution ranges.

WRECKAGE AND IMPACT INFORMATION

Review of photos taken by airport personnel revealed scars in the asphalt surface of taxiway A that led from the helicopter's initial impact point about 80 feet south to its final resting position. The scars at the initial impact point were consistent with the helicopter's skids and tail section contacting the pavement. The scars corresponding to the skids were initially parallel to the centerline of the taxiway before deviating to the left and leading to the helicopter, which was sitting upright on an easterly heading. The helicopter's tail boom was separated from the fuselage and remained attached only by wires. The tail rotor guard was separated, the lower vertical fin was bent to the right, and both tail rotor blades were damaged. There was no apparent damage to the main rotor blades.

The helicopter was recovered from the taxiway to the ramp where it was examined on October 30, 2013, by the NTSB investigator-in-charge, an FAA inspector, and a mechanic employed by the operator. The governor switch was found in the "AUTO" position, and the twist grips were found in the full open throttle position with the "FLIGHT" stop on the right side grip disengaged. According to the flight instructor, he moved the governor switch from the "MAN" to the "AUTO" position after the helicopter came to a stop. It is unknown whether the twist grips or "FLIGHT" stop were moved before the examination took place.

The engine was visually examined, and no anomalies were noted. The twist grip was rotated through its full range of motion while the operator's mechanic observed the movement of the throttle linkage at the HMU; no binding or other anomalies were noted with the operation of the manual throttle control system. The throttle friction control wheel on the right collective was loosened and tightened, and, as expected, the twist grip became easier and more difficult, respectively, to rotate.

The master switch was turned on, and the flight report for the accident flight was reviewed on the Vehicle Engine Multifunction Display (VEMD). According to the VEMD, the flight number was 2644 and the recorded duration of the flight was 21 minutes. This recorded time started when the engine accelerated through 60% Ng, and ended when it decelerated through 10% Ng and the Nr decreased below 70 rpm. There were no over-limits or failures recorded.

Following the examination, the engine, the DECU, and the VEMD were removed from the helicopter for further examination and testing.

TESTS AND RESEARCH

On December 12, 2013, the VEMD was examined at the facilities of American Eurocopter located in Grand Prairie, Texas. The examination confirmed that the data recorded by the VEMD for the accident flight showed no over-limits or failures. A few of the most recent flights before the accident flight were reviewed, and no over-limits were recorded.

On December 12, 2013, a download of data recorded by the DECU was conducted at the facilities of Turbomeca USA in Grand Prairie, Texas. No faults were recorded during the accident flight. The download of the DECU matched the results of the VEMD examination.

On December 12, 2013, the engine was examined and test run at the facilities of Turbomeca USA. The engine was installed in a test cell, started, and tested in both automatic and manual governor modes. No anomalies or un-commanded shutdowns were experienced, and the engine's performance during all tests conducted met the manufacturer's specifications.

Your Worst Day...by April DiChiara

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He Who Cannot Remember the Past is Condemned to Repeat It...

It may be up to you...

How well do you think "see and avoid" works at preventing mid-air collisions? An investigator in charge of determining the cause of a mid-air between two planes flying over the Grand Canyon in 1956 came to the conclusion that see and avoid doesn't work. His findings led to positive air-traffic-control of commercial airliners. We in HEMS do not have the same level of control over our flights.

While HEMS hasn't suffered a mid-air collision between two helicopters since the collision in Flagstaff Arizona., there are more of us flying now than ever before - not to mention news-helicopters, law-enforcement, fire-fighting etc.  Competition and ever-rising reimbursements have led to different companies' helicopters frequently arriving and departing hospital helipads with scant notice of each other's intentions or actions...

Flagstaff Crash Scene photo by David Tedesco

Last evening, while approaching a hospital in Huntsville Alabama, I became aware of a competitor's aircraft occupying the single-spot helipad only after flying over the hospital for landing. About three hours later, our roles were reversed as I was loading a patient and  preparing to depart that same pad on another flight - and the other company's aircraft broke off his approach only after I flashed my landing lights. He had no idea that I was there...

Notwithstanding see-and-avoid and radio-calls in the blind, the relative freedom of  Visual-Flight-Rules (VFR)  to uncontrolled hospital helipads creates an increased risk of a mid-air collision, or a collision on landing. 

The Shands Hospital in Gainesville, Florida has instituted near-positive control of arrivals and departures from their helipads - perhaps such increased control is a good thing...

There is also a hazard associated with channelizing traffic across check-points or in corridors. Helicopter crashes at both the Fort Campbell Kentucky and Fort Stewart Georgia military reservations, involving air corridors and choke-points pointed out the need for procedural separation and increased control.

An example: In Huntsville Alabama, the main hospital is located between a mountain ridge-line and restricted airspace- forming a north-south channel that all HEMS aircraft use. At the south end of this channelizing phenomenon, there is a VFR checkpoint (bridge over river) depicted on the sectional map. It is entirely probable that multiple aircraft could be in this corridor heading in opposite directions. With multiple radios in use, a radio advisory could easily be missed. The lights on a low flying helicopter can easily get mixed in with ground lights...

A local area letter-of-agreement (LOA), endorsed by all area HEMS programs, agreeing to separate traffic along channelizing routes with choke points by procedure or altitude, ; for example... odd altitudes heading south and even altitudes heading north - flying west of the road heading south and east of the road heading north (fly right) - making an advisory radio call approaching choke-points; could present another layer of defense against the risk of a mid-air. Even if published, we must remember that everyone may not be aware of our LOA and procedures, but something is better than nothing. This agreement to cooperate should start with the senior leaders from all the companies involved - but they may be too busy. It may be up to you - to save your own life.

Another hazard-mitigation practice is the absolute dedication to professionalism and courtesy by all HEMS pilots (and crews) in an area. Yes, we work for different companies. Yes, we want our programs to do well. But that should never equate to a refusal to communicate or cooperate with another pilot or crew. As Dutch Martin used to say, "we are all just glad to have a job - and trying to do it." It is easy to fall into an "us-versus -them" mindset, and hesitate to communicate with each other.

But our lives may depend on us doing just that...

safe flights

Needle Decompression of the Chest...3.5 minute video from the Trauma Professional's Blog..."A really big needle!"

mailto:Michael.D.McGonigal@HealthPartners.com

Vanderbilt LifeFlight Crew Meets Child Saved

Accidents involving children are the worst...

 LifeFlight nurses who lifted off from Smyrna responded to the accident and found Mason on his side, still in his car seat nearly 30 feet away from the car

The seat belt restraint had been severed during the accident, sending Mason flying onto Highway 231. When LifeFlight medics looked at the car they couldn't believe their eyes. There was barely anything left of the car Mason and his father were driving. They transported Mason to Vanderbilt Children's Hospital after putting in a breathing tube and supporting his fragile body.

Click here for full story...

Would We Be Ready?

 "The employee said the pilot then simultaneously brought the helicopter up off the pad and forward. He described the takeoff as "kind of shaky." He said that on other flights, pilots will normally bring the helicopter into a hover, do an instrument check, and then start forward flight. However, in the three times he had flown with the accident pilot, he always took off without hovering."


This is an account of an engine failure in a Bell 206, in the Gulf Of Mexico. While it does not involve EMS, it DOES involve a helicopter many of us work in. There are lessons to be learned here...   CEN14FA004
"The following is an INTERIM FACTUAL SUMMARY of this accident investigation. A final report that includes all pertinent facts, conditions, and circumstances of the accident will be issued upon completion, along with the Safety Board's analysis and probable cause of the accident:"

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HISTORY OF FLIGHT

On October 9, 2013, about 0720 central daylight time, a Bell 206L-3, N54LP, was substantially damaged when it impacted water shortly after takeoff from the Main Pass 107D oil platform in the Gulf of Mexico. The commercial pilot was fatally injured and the three passengers were seriously injured. The helicopter was registered to and operated by Panther Helicopters, Inc., Belle Chasse, Louisiana. A company visual flight rules flight plan was filed for the flight that was destined for the Belle Chasse Heliport (06LA), Belle Chasse, Louisiana. Visual meteorological conditions prevailed for the business flight that was conducted under the provisions of 14 Code of Federal Regulations Part 135.

The purpose of the flight was a routine crew change at the MP107D oil platform. The pilot and three oil platform employees departed 06LA about 0633 and flew direct to the platform. The crew change consisted of dropping the three platform employees off, picking up three other employees, then returning to 06LA. After landing on the platform, the pilot did not shut down the helicopter down and stayed at the controls with the main rotor turning until the crew change was complete.

A witness was standing on the MP108E oil platform, which was about 300-400 yards from MP107D. He had a clear and unobstructed view of the MP107D platform and saw the helicopter sitting on the helipad with its main rotor blades turning. The helicopter was facing east-northeast. The witness said that he saw three people get off the helicopter and then three other people get on the helicopter. He described the weather as "stale" and the wind sock was "limp."

About 1 to 2 minutes later, the witness observed the helicopter pull up into a 3 to 4-foot-high hover over the helipad and make a slight bearing change toward the east. He said at that point, everything was completely normal with the helicopter. The helicopter then moved forward and started to take off toward the east. The witness said as soon as the helicopter cleared the helipad's skirting, he saw a flash and a large (10-foot-high x 10-foot-wide) "poof" or "cloud" of white smoke come from directly under the main rotor blades near the exhaust section of the helicopter. This was followed by a loud, high-pitched, screeching noise, as if the engine were being revved up. The witness said this "poof" of smoke occurred when the helicopter was parallel to a flare boom that extended directly out from the platform and was positioned on the north side of the helipad. The witness said that after he saw the "poof" of smoke, the helicopter nosed over toward the water. The helicopter cleared the helipad's skirting and did not strike the flare boom as it descended.

The witness said he saw the helicopter's emergency floats fully expand before it impacted the water. The helicopter hit the water hard with the main rotors still turning; became completely submerged and rolled inverted. The wintess could see the helicopter's skids near the surface of the water and noted that one emergency float (he could not recall which one) had completely separated from the helicopter.

The witness did not see anyone coming to the surface and used his VHF handheld radio to issue a "may-day-call." He also directed a field boat, which was at the base of the MP108E platform, to the helicopter. He said that by the time the boat arrived, two deck hands were already stripped down and jumped into the jellyfish infested water to help the occupants of the helicopter. Although one of the deckhands had an allergic reaction to the jellyfish stings, they were able to get three of the four occupants out of the helicopter and onto the field boat. The pilot's feet were "caught up in the controls" and it took about 15 minutes for them to get him freed.

The witness said he did not see any methane gas being vented from the flare boom on the morning of the accident; however, he did see a large (size of an automobile) "methane cloud" coming from the flare boom the day before the accident between 12 and 5 pm. The methane cloud was located right where he saw the poof of white smoke on the day of the accident. The witness said he has seen methane being vented from the MP107D flare boom on several occasions. He said they vent "a lot of gas" several times a week.

In a telephone conversation, a platform employee, who was a passenger on the helicopter, stated that he had just completed a 14-day "hitch" on the MP107D oil platform and was headed back to Louisiana. On the morning of the accident, he and the two other platform employees prepared the platform for a crew change and waited for the helicopter to arrive. The employee said that after the pilot landed, he briefly talked to one of the on coming employees about a hunting trip. He then loaded his bags and was the last one to board the helicopter. The employee said he got in the helicopter via the left rear door and sat in the left seat, facing forward. The passenger then donned an inflatable life vest, put on a headset, and fastened his seatbelt. He tugged on the seatbelt to make sure it was secure and snug.

The employee said that once everyone was fastened in, they gave the pilot a "thumbs-up" and the pilot prepared to depart. At this point, everything regarding the flight was "normal."

The employee said the pilot lifted the helicopter up off the platform and began forward flight. When the helicopter was over the water, he heard a loud noise overhead as if the transmission was coming a part. The other passenger that was seated next to him asked, "What's that?" The employee told him to "hold on," and the next thing he knew they hit the water with a "big splash." Prior to impact, he did not hear any alarms going off in the cockpit and did not remember the emergency floats expanding. The pilot did not say anything during the accident sequence.

The employee stated that he may have passed out for a few minutes. When he regained consciousness, he realized he was out of his seatbelt (he did not recall unfastening the buckle). The helicopter had rolled on-to its left side, and he was trying to find the door. When he tried to stand up, he realized he couldn't feel his legs. At this point, the passenger, who had been seated next to him had opened the right door and was climbing out. Although water was entering the cabin, he and the passenger in the front left seat were able to keep their heads above water. There was no movement or response from the pilot.

The passenger said that he sat there for a few minutes, and when the helicopter began to roll inverted, he was able to push himself out of the right rear door where the other rear seat passenger had been sitting. He then tried to inflate his life vest, but when he pulled on the inflation-lanyard it would not inflate. He said that he was not familiar with this particular model vest and he did not try to self-inflate the vest. Shortly after, the front seat passenger was able to get out of the helicopter. The two rescuers who dove in the water from the life boat were trying to get the pilot out, but his seatbelt was "too tight," and his foot was stuck in the windshield.

The employee said that while the pilot was being extracted, the other rear seat passenger was dragged to the life boat via a life ring. At this time, the employee saw a life vest floating in the water. He was able to inflate it and used it to support himself until he was rescued. The employee said he was in a "panic state of mind" and didn't recall getting onto the boat.

In a telephone conversation, another platform employee, who was also a passenger on the accident flight, stated that he had just completed a 14-day "hitch" on the MP107D oil platform. He said that on the morning of the accident, he and the two other employees prepared the platform to be turned over to the on-coming crew. While eating breakfast, he heard the pilot make a radio call that he was 10 minutes out with three onboard. The employee said the platform's lead operator responded to the pilot, and told him he had a "green deck" to land. The employee then grabbed his bags and headed up to the helipad. After the helicopter landed, the three on-coming crew members got off the helicopter and retrieved their bags from the cargo bay. The employee said he placed his bags in the cargo bay and walked around the front of the helicopter. The pilot gave him a "thumbs-up" and a smile, and then the employee got in the helicopter. He sat in the rear of the helicopter on the right side, facing forward. He donned the provided inflatable life vest, a headset, and fastened his seatbelt assembly. The employee said another employee sat next to him on the left side, forward facing seat and the other sat in the front left seat.

The employee said he did not talk to the pilot or notice anything unusual about his behavior. After the crew was onboard, the pilot asked if they were ready to go and they responded they were ready. The employee said the pilot then simultaneously brought the helicopter up off the pad and forward. He described the takeoff as "kind of shaky." He said that on other flights, pilots will normally bring the helicopter into a hover, do an instrument check, and then start forward flight. However, in the three times he had flown with the accident pilot, he always took off without hovering.

The employee said that once the helicopter moved off the helipad and over the water, there was a "winding noise" then a "pop" sound. His first instinct was that there was a problem with the transmission. He did not hear alarms going off in the cockpit or see any annunciator lights. The helicopter then nosed over at an angle toward the water. The employee said that as the helicopter descended, the emergency floats expanded just before they hit the water. He described the impact as a "big ole crash like landing on concrete." The employee said that he then heard moans of pain coming from the other men onboard and that water started to enter the cabin. The helicopter had rolled on to its left side. He then undid his seatbelt and opened the right cabin door. The employee said he turned left and asked the passenger next to him if he was okay, and he responded that he could not feel his legs. The employee said the passenger had come completely out of his seatbelt during the impact.

The employee exited the helicopter and held onto the skid of the helicopter because when he pulled on his life vest inflation-lanyard, it did not expand. He said the rear seat passenger's life vest also wouldn't inflate but the passenger's vest on the front seat did inflate. He was not sure about the pilot's life vest.

The employee said he saw the lift boat and told the rescuers there were three more people on board. He was able to get onto the life boat, where he laid down until help arrived.

The employee reiterated several times there was nothing mechanically wrong with the helicopter until they started to takeoff. He said the platform was not venting methane that morning and the wind was calm.

In a telephone conversation, one of the platform employees, who had just been dropped off at the platform, stated that he and the two other platform employees arrived at Panther Helicopter's facility in Belle Chasse, Louisiana, on the morning of the accident around 0600. He said all three of them signed in and waited for the helicopter to be ready. When they were ready to board, he got in the front left seat, put on his life vest and fastened his seatbelt. The pilot made sure everyone was wearing their life vests and seatbelts before they departed. While en route, the employee said he briefly spoke to the pilot and he did not notice anything unusual with his demeanor. He said the helicopter was operating fine and there were no indications of any problems.

The employee said that after a normal landing, he exited the helicopter, retrieved his bags from the cargo bay, and went downstairs into the platform housing. There he had a quick changeover briefing with the departing-lead. Several minutes later, he heard the helicopter's engine spool up as it prepared to takeoff. Everything sounded normal until he heard a "pop" and a high-pitched whine followed by a low pitch whine as if the engine were spooling down. He described the noise as a turbine or compressor winding down. At that point, the employee knew something was wrong and ran outside. Once outside, he saw the helicopter in the water on its right side and one passenger was exiting the helicopter. The employee said he went back inside and called the Coast Guard, Panther Helicopters, and his senior management.

According to the operator, the helicopter was equipped with a SkyConnect tracking system. The last registered altitude of the helicopter was about 141 feet.

PILOT INFORMATION

The pilot held a private pilot certificate for airplane single-engine land and a commercial pilot certificate for rotorcraft-helicopter. His last Federal Aviation Administration (FAA) second class medical was issued on January 10, 2013. According to the operator, the pilot had accrued a total of 3,450 total hours; of which 3,423 hours were in helicopters, and 177 hours were in the same make/model as the accident helicopter.

The pilot was hired by Panther on June 17, 2013. His training was conducted by Panther in the Bell 206 helicopter. The pilot successfully completed his CFR Part 135.293 and 135.299 FAA check ride on July 25, 2013.

AIRCRAFT INFORMATION

N54LP was a 1991 Bell 206L-3 helicopter with serial number 51466. The single-engine helicopter was powered by an Allison M250-C30P turbo-shaft engine with serial number CAE 895524, which drove a two-bladed main rotor system and a two-bladed tail rotor. The helicopter was configured to carry one pilot and six passengers.

According to the operator, the helicopter was maintained in accordance with the manufacturer's continuous inspection program. The helicopter's last inspection (event 2) was completed on October 3, 2013. The helicopter's total time at the time of the accident was 11,238 hours.

METEOROLOGICAL INFORMATION

At 0600, weather conditions at the Belle Chasse heliport, Belle Chasse, Louisiana, about 72 nautical miles northwest of the accident site were calm wind, visibility 10 miles and clear skies, with a temperature of 65 degrees Fahrenheit.

At 0655, weather conditions at the New Orleans Naval Air Station (NBG), Louisiana, about 72 miles northwest of the accident site were calm winds, visibility 10 statute miles with shallow fog, few clouds at 5,000 feet, temperature 57 degrees F, dew point 60 degrees F, and altimeter 30.06 inches of Mercury.

AIRPORT INFORMATION

According to the Bureau of Safety and Environmental Enforcement, the Gulf of Mexico is divided into three primary subdivisions: Western Gulf of Mexico, Central Gulf of Mexico, and Eastern Gulf of Mexico. The three subdivisions are further divided into areas and blocks. The blocks are about 3 miles long and 3 miles wide and are used for oil/gas lease identification. There are over 2,600 offshore production platforms in the Gulf of Mexico region.

MP107D is an offshore oil production platform, (29 degrees 30 minutes north latitude and 88 degrees 42 minutes west longitude). MP107D is about 37 nautical miles northeast of Venice, Louisiana. MP107D features a single helideck (about 35-feet-long and 35-feet-wide).

WRECKAGE INFORMATION

The wreckage was recovered and moved to Panther's maintenance facility in Belle Chasse, Louisiana. The National Transportation Safety Board (NTSB) Investigator-in-Charge conducted an examination of the airframe and a visual examination of the engine on October 14, 2013. Also present for the examination were representatives of Panther, Rolls Royce, and Bell Helicopter.

The helicopter was secured and upright on a flatbed trailer. The engine, transmission, and main rotor system remained attached to the airframe. One of the main rotor blades had been cut off for transport and the other blade was fractured during the impact with the water. The section of fractured blade was never located. The tail boom had separated from the fuselage about 12-inches aft of the tail boom attachment point. The tail rotor assembly had separated aft of the elevator and was never recovered.

The entire windshield on the right side of the helicopter was missing, and a large section of windshield was missing on the left side. The forward and aft passenger doors were removed. The aft cargo bay was crushed upward from the bottom of the fuselage. Salt water corrosion was noted throughout the fuselage and engine.

Flight control continuity was confirmed for the cyclic and the collective to the main rotor system. Partial flight control continuity was established for the anti-torque pedals from the cockpit to the point where the tail boom had separated from the fuselage.

The throttle was locked in the fuel-cutoff position, which was consistent with the setting on the fuel control unit.

Examination of the pilot's 4-point shoulder harness/seatbelt assembly revealed that it was secure at all fuselage attach points. The inertial reel was locked, and stretch marks on the belt material were observed in several locations. The latching mechanism functioned normally when manually tested.

The front seat passenger's 4-point shoulder harness/seatbelt assembly was also secure at all fuselage attach points and functioned normally when manually tested. The inertial reel was not locked.

The metal seatbox for the front passenger's seats was crushed downward.

All of the rear seat shoulder harness/seatbelt assemblies were secured at their respective fuselage attachment points and the latching mechanisms functioned normally when manually tested.

A visual examination of the engine revealed that it did not sustain much impact damage; however, several large holes were observed in the exhaust collector support stack. A hole was also observed in the cowling on the right side near the area of the support stack. Oil was in the bottom of the engine pan and the forward engine mounts were slightly bent. All engine fuel, oil and pneumatic lines, and b-nut fittings were tight and no leaks were observed.

The engine was removed and shipped to Rolls Royce, where a tear down examination was conducted on November 6-7, 2013, under the supervision of an NTSB investigator. Representatives of the FAA, Rolls Royce, Panther and Bell Helicopter were also present for the exam.

The centrifugal compressor section was disassembled. The #1 and #2 bearings were examined and found to be free of any indications of distress. The compressor impellor vanes exhibited slight indications of rotational rubbing; however, no other indications of ingestion or other damage were noted.

The gearbox was disassembled. Examination of internal components did not reveal any obvious defects to gearing. The gearbox interior contained a large quantity of the magnesium gearbox case, corrosion deposits and material from the effects of sea water immersion and recovery operations.

The gas generator turbine and power turbine sections were disassembled. The Stage 1 turbine section was undamaged. The Stage 2 section revealed damage to the turbine disk blades, with one blade liberated from the blade root. All of the Stage 3 turbine disk blades were liberated at the blade roots. All of the Stage 4 turbine disk blades were damaged, with about 320 degrees of the blade shrouds detached. The blades did not breach the turbine cases.

The turbine section stages were retained and are currently undergoing metallurgical examination.

MEDICAL AND PATHOLOGICAL INFORMATION

Toxicological testing was conducted by the FAA Toxicology and Accident Research Laboratory, Oklahoma City, Oklahoma. The pilot tested positive for Cetirizine in his blood and urine. Diphenhydramine was detected in his urine and blood (.024ug/ml, ug/g). In addition, Ibuprofen was detected in the pilot's urine.

Editor's note: During annual recurrent ground school recently, the instructor mentioned that pushing forward on the cyclic immediately following an engine failure out-of-ground-effect will result in loss of rotor rpm. The urge to push forward must be resisted until the rotor system completes it's transition from normal thrusting state (air being driven down through the rotor system) to autorotational state, (air passing up through the rotor system and driving the rotor). The indication that this transition is complete is an increase in rotor rpm...

More about Vortex Ring State...

Recently, I wrote about Vortex Ring State... Click here for that post...

This is what the aftermath of VRS looks like...

 

 

NTSB Identification: CEN14CA252
14 CFR Part 91: General Aviation
Accident occurred Sunday, May 25, 2014 in Constantine, MI
Probable Cause Approval Date: 06/18/2014
Aircraft: AEROSPATIALE AS 365 N2 DAUPHIN, registration: N365WM
Injuries: 3 Uninjured.

NTSB investigators used data provided by various entities, including, but not limited to, the Federal Aviation Administration and/or the operator and did not travel in support of this investigation to prepare this aircraft accident report.
The pilot reported that he positioned the helicopter to land on a westerly heading with the light and variable wind from the west. About 200 feet above the ground he noticed that the helicopter was descending so he increased the collective to arrest the rate of descent. The torque gage was increasing from 50% to 60%. He lowered the collective in attempt to get into clean air and then pulled back on the cyclic to arrest the forward airspeed. The pilot attempted to control the helicopter to the ground, maintain an upright attitude, and avoid obstacles. The helicopter landed hard and bounced once before it came to rest in the parking lot. The pilot reported no preaccident mechanical malfunctions or failures with the helicopter that would have precluded normal operation. A video of the accident sequence was reviewed and matched the pilot's statement. The video did not reveal any anomalies with the helicopter or the engine sounds. A postaccident examination revealed substantial damage to the right fuselage and lower right vertical stabilizer. The video evidence and pilot statement are consistent with the helicopter entering a vortex ring state (settling with power) condition, which allowed the helicopter to descend more rapidly than expected and land hard. The National Transportation Safety Board determines the probable cause(s) of this accident to be:
The pilot's loss of control while entering a vortex ring state (settling with power) condition, which resulted in a hard landing.