Saturday, November 07, 2020

Pilatus PC-12 NGX, N400PW: Accident occurred November 06, 2020 in Hilo, Hawaii


This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed.

The National Transportation Safety Board did not travel to the scene of this accident.

Additional Participating Entities:
Federal Aviation Administration / Flight Standards District Office; Honolulu, Hawaii
Pilatus Aircraft Ltd; Stans, Switzerland
Pratt & Whitney Canada; Quebec

https://registry.faa.gov/N400PW 

Location: Hilo, HI 
Accident Number: ANC21LA006
Date & Time: November 6, 2020, 16:00 Local 
Registration: N400PW
Aircraft: Pilatus PC12 
Injuries: 2 None
Flight Conducted Under: Part 91: General aviation - Ferry

On November 6, 2020, about 1600 Pacific standard time, a Pilatus PC-12, N400PW, was substantially damaged when it was ditched in the Pacific Ocean about 1000 miles east of Hilo, Hawaii. The two pilots sustained no injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 ferry flight.

According to the pilot-in-command (PIC), who was also the ferry company owner, he and another pilot were ferrying a new airplane from California to Australia. The first transoceanic leg was planned for 10 hours from Santa Maria Airport (KSMX), Santa Maria, California to Hilo Airport (PHTO), Hilo, Hawaii. The manufacturer had an auxiliary ferry fuel line and check valve installed in the left wing before delivery. About 1 month before the trip, the pilot hired a ferry company to install an internal temporary ferry fuel system for the trip. The crew attempted the first transoceanic flight on November 2, but the ferry fuel system did not transfer properly, so the crew diverted to Merced Airport (KMCE), Merced, California. The system was modified with the addition of two 30 psi fuel transfer pumps that could overcome the ferry system check valve. The final system consisted of 2 aluminum tanks, 2 transfer pumps, transfer and tank valves, and associated fuel lines and fittings. The ferry fuel supply line was connected to the factory installed ferry fuel line fitting at the left wing bulkhead, which then fed directly to the main fuel line through a check valve and directly to the turbine engine.  The installed system was ground and flight checked before the trip.

According to Federal Aviation Administration automatic dependent surveillance broadcast (ADS-B) data, the airplane departed KSMX about 1000. The pilots each stated that the ferry fuel system worked as designed during the flight and they utilized the operating procedures that were supplied by the installer. About 5 hours after takeoff, approaching ETNIC intersection, the PIC climbed the airplane to flight level 280. At that time, the rear ferry fuel tank was almost empty, and the forward tank was about 1/2 full. The crew was concerned about introducing air into the engine as they emptied the rear ferry tank, so the PIC placed the ignition switch to ON. According to the copilot (CP), she went to the cabin to monitor the transparent fuel line from the transfer pumps to ensure positive fuel flow while she transferred the last of the available rear tank fuel to the main fuel line. When she determined that all of the usable fuel was transferred, and fuel still remained in the pressurized fuel line, she turned the transfer pumps to off and before she could access the transfer and tank valves, the engine surged and flamed out. The PIC stated that the crew alerting system (CAS) fuel low pressure light illuminated about 5 to 15 seconds after the transfer pumps were turned off, and then the engine lost power and the propeller auto feathered. The PIC immediately placed the fuel boost pumps from AUTO to ON. The CP went back to her crew seat and they commenced the pilot operating handbook’s emergency checklist procedures for emergency descent and then loss of engine power in flight.

According to both crew members, they attempted an engine air start. The propeller unfeathered and the engine started; however, it did not reach flight idle and movement of the power control lever did not affect the engine. The crew secured the engine and attempted another air start. The engine did not restart and grinding sounds and a loud bang were heard. The propeller never unfeathered and multiple CAS warning lights illuminated, including the EPECS FAIL light (Engine and Propeller Electronic Control System). The crew performed the procedures for a restart with EPECS FAIL light and multiple other starts that were unsuccessful. There were no flames nor smoke from either exhaust pipe during the air start attempts. About 8,000 ft mean sea level, the crew committed to ditching in the ocean.

About 1600, after preparing the survival gear, donning life vests, and making mayday calls on VHF 121.5, the PIC performed a full flaps gear up landing at an angle to the sea swells and into the wind. He estimated that the swells were 5 to 10 ft high with crests 20 feet apart. During the landing, the pilot held back elevator pressure for as long as possible and the airplane landed upright. The crew evacuated through the right over wing exit and boarded the 6 man covered life raft. A photograph of the airplane revealed that the bottom of the rudder was substantially damaged. The airplane remained afloat after landing. See figure 1.

The crew utilized a satellite phone to communicate with Oakland Center. The USCG coordinated a rescue mission. About 4 hours later, a C-130 arrived on scene and coordinated with a nearby oil tanker, the M/V Ariel, for rescue of the crew. According to the pilots, during the night, many rescue attempts were made by the M/V Ariel; however, the ship was too fast for them to grab lines and the seas were too rough. After a night of high seas, the M/V Ariel attempted rescue again; however, they were unsuccessful. That afternoon, a container ship in the area, the M/V Horizon Reliance, successfully maneuvered slowly to the raft, then the ship’s crew shot rope cannons that propelled lines to the raft, and they were able to assist the survivors onboard. The pilots had been in the raft for about 22 hours.
The airplane was a new 2020 production PC-12 47E with a newly designed Pratt and Whitney PT6E-67XP engine which featured an Engine and Propeller Electronic Control System. The airplane is presumed to be lost at sea. The investigation is ongoing.

Aircraft and Owner/Operator Information

Aircraft Make: Pilatus 
Registration: N400PW
Model/Series: PC12 47E 
Aircraft Category: Airplane
Amateur Built: No
Operator: 
Operating Certificate(s) Held: None
Operator Designator Code:

Meteorological Information and Flight Plan

Conditions at Accident Site: VMC 
Condition of Light: Day
Observation Facility, Elevation: 
Observation Time:
Distance from Accident Site:
Temperature/Dew Point:
Lowest Cloud Condition: Few / 2000 ft AGL 
Wind Speed/Gusts, Direction: / ,
Lowest Ceiling: None
Visibility:
Altimeter Setting:
Type of Flight Plan Filed:
Departure Point:
Destination:

Wreckage and Impact Information

Crew Injuries: 2 None 
Aircraft Damage: Substantial
Passenger Injuries:
Aircraft Fire: None
Ground Injuries: 
Aircraft Explosion: None
Total Injuries: 2 None
Latitude, Longitude: 27.5937,-139.6529



HONOLULU, Hawaii — The United States Coast Guard and a pair of good Samaritans responded to a downed aircraft approximately 1,100 miles northeast of Oahu on November 6th.

The Coast Guard says there were two crew members in the Pilatus PC-12 NGX, and no injuries have been reported.

Officials say the Joint Rescue Coordination Center received reports of a downed aircraft around 2:30 p.m.

The Joint Rescue Coordination Center then issued an Urgent Marine Information Broadcast and directed air units from Air Station Barbers Point to their location. 

All vessels over 20 meters in length within United States waters are required to monitor Urgent Marine Information Broadcast channels.

Two good Samaritans in the area also responded to the Urgent Marine Information Broadcast and set a course to the downed aircraft location.

The Coast Guard and good Samaritans arrived at the scene around 7:15 p.m.

25 comments:

  1. What is a Pilatus PC-12 doing 1,100 miles northeast of Oahu??? -- Besides running out of fuel. Way, way too far away from land to possibly return with remaining fuel. Looks like misconduct.

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    Replies
    1. Correction. I wrote the above post and believe I got it all wrong. This was a ferry flight from just north of LA all the way to Hilo. Also, the pilots were both rescued which tells you at least three things:

      1) Pilots did a very good job alerting the area that they were in trouble ... otherwise a ship wouldn't have been there shortly after their ditching.

      2) The two pilots survived the crash ... which means they did a nice job of setting plane down on the water gently. That's a lot easier to coach and teach and talk about than it is to actually perform. Ask the instructor how many times he or she has ditched an airplane. (Answer = zero).

      3) Got themselves safely into a raft before the plane sunk.

      They did a great job. Glad they're safe.

      Delete
    2. PC 12’s are used on inter island flights. This is a brand NGX SN 2002.

      Delete
    3. Thank you for correcting yourself. I can say with a first hand professional relationship with one of the pilots that they are an exceptionally experienced and competent pilot and a wonderful person as well.

      Delete
  2. This was not in Honolulu county Hawaii. It was in International waters somewhere around ENTIC Waypoint. Just about halfway between SMX and ITO. About 1100 Mi either way.
    Flight Plan info:

    KSMX GVO ELKEY R577 EBBER ITO PHTO

    KSMX 34.8999444 -120.4580833 141° n/a 2355 0 Origin Airport
    GVO 34.5313889 -120.0911111 222° 33 2367 33 VOR-TAC (NAVAID)
    ELKEY 32.6833639 -122.0510083 255° 171 2223 179 Reporting Point
    EDTOO 32.4667000 -123.0010250 257° 57 2166 223 Reporting Point
    EDSEL 32.2423417 -124.0985750 255° 66 2100 279 Reporting Point
    ETECO 30.2858333 -131.6361111 251° 466 1635 725 WAY-PT
    ETNIC 27.9116667 -138.8566667 248° 466 1169 1186 WAY-PT
    ERROT 25.2761111 -145.5108333 245° 450 720 1634 WAY-PT
    ELOYI 22.3441667 -151.8852778 242° 451 273 2085 WAY-PT
    EBBER 21.7134333 -153.1472833 222° 92 185 2176 Reporting Point
    ITO 19.7213889 -155.0108333 268° 183 2 2352 VOR-TAC (NAVAID)
    PHTO 19.7202630 -155.0484701 n/a 2 0 2355 Destination Airport

    JW

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  3. Fuel shouldn't have been an issue as the NGX has a range of 1700-1800 miles with full fuel and two pilots, but, the aircraft was fitted with a 3rd party ferry tank installed with an unknown quantity and weight of fuel. So if the rigging, or setup of the tank(s) was improperly installed, fuel exhaustion could be a factor.
    The distance between the two airports is 2355 NM.
    Luckily the two ferry pilots survived and were rescued by a passing ship.

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  4. PC-12 Pilot's Operating Handbook and FOCA approved
    3.9.9 DITCHING
    1. Landing gear UP
    Heavy swell with light wind, ditch parallel to the swell. Strong wind, ditch
    into the wind.
    2. Passengers Brief
    3. Flaps 40°
    4. Final approach speed 84 KIAS
    5. CABIN PRESS switch DUMP
    6. Ditch with a low rate of descent.
    7. Electrical Power EMERGENCY OFF (use
    MASTER POWER switch)
    8. Evacuate through the overwing emergency exit only.

    ReplyDelete
  5. "In the July 8, 2007 PC-12 ditching, the pilot reported that the airplane was in cruise at 26,500 ft when he felt a vibration followed by a rapid increase in the engine’s turbine temperature indication (TTI). He reported that the TTI reached 1,144 deg C, at which point there was a compressor stall. He shut down the engine, feathered the propeller and entered a power-off emergency descent. After spending 15 hr in a life raft, the pilot and all three passengers were safely recovered some 60 mi from the Russian coast in the icy Sea of Okhotsk." @ ainonline com

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    Replies
    1. There is no TTI indicator. There is a ITT (Interstage Turbine Temperature indicator). The ITT indication system monitors the temperature of the gas flow through the engine at station 4.5 for the Pratt & Whitney PT6.
      The system supplies turbine temperature information via the EEC to the EICAS for display in the flight compartment for the given engine operating conditions. Station 4.5 is called the interstage or the stages between the HP and Low pressure Turbines. This enables the flight crew to monitor the ITT temperature during engine operation and take proper action to prevent the thermodynamic limits of the engine from being exceeded. Temperature probes are permantly installed at location T4.5 between the HP an LP Turbines. The temperature reading is adjusted against T8 in the EEC for average. The engine has what is called a thermodynamic limit and this is monitored by the EEC, if this Temperature should be exceeded, the EEC will signal the FADEC and the engine will auto shutdown.
      ITT, N2 and Fuel flow give unique indicators about engine life and any rise of the three parameters should cause concern. Engine wash or turbine wash can effectively lower ITT because of Sulphirdation on the turbine blades. Turbine tip clearance or tip wear can cause degraded engine performance, higher ITT and increased Fuel flow.

      TIT = Turbine Inlet Temperature. A position forward of the 1st stage turbine inlet guide vanes. The hottest most hostile area in the engine.

      ITT = Interstage Turbine Temperature. A position somewhere between TIT and EGT.

      EGT = Exhaust Gas Temperature. The position just aft of the last turbine wheel.
      TechRep

      Delete
    2. There is no TTI indicator. There is a ITT (Interstage Turbine Temperature indicator). The ITT indication system monitors the temperature of the gas flow through the engine at station 4.5 for the Pratt & Whitney PT6.
      The system supplies turbine temperature information via the EEC to the EICAS for display in the flight compartment for the given engine operating conditions. Station 4.5 is called the interstage or the stages between the HP and Low pressure Turbines. This enables the flight crew to monitor the ITT temperature during engine operation and take proper action to prevent the thermodynamic limits of the engine from being exceeded. Temperature probes are permantly installed at location T4.5 between the HP an LP Turbines. The temperature reading is adjusted against T8 in the EEC for average. The engine has what is called a thermodynamic limit and this is monitored by the EEC, if this Temperature should be exceeded, the EEC will signal the FADEC and the engine will auto shutdown.
      ITT, N2 and Fuel flow give unique indicators about engine life and any rise of the three parameters should cause concern. Engine wash or turbine wash can effectively lower ITT because of Sulphirdation on the turbine blades. Turbine tip clearance or tip wear can cause degraded engine performance, higher ITT and increased Fuel flow.

      TIT = Turbine Inlet Temperature. A position forward of the 1st stage turbine inlet guide vanes. The hottest most hostile area in the engine.

      ITT = Interstage Turbine Temperature. A position somewhere between TIT and EGT.

      EGT = Exhaust Gas Temperature. The position just aft of the last turbine wheel.
      TechRep

      Delete
    3. July 8, 2001,
      "Pilot Michael S. Smith of Boise, Idaho, was flying three Japanese passengers 27,000 feet over the Sea of Okhotsk east of Russia on July 8, 2001, when the plane’s engine began vibrating and making strange noises." https://www.denverpost.com/2007/06/10/planes-dive-spawns-lawsuit/

      Delete
  6. Great ending to a big time emergency that could have gone very wrong. These pilots knew how to survive. Wonder if they will share what went wrong!

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  7. Pretty sure they were using ferry tanks, if something went screwy with the plumbing and the engine experienced fuel interruption and flameout at 30,000, the procedure is to wait until below at least 20k to attempt restart, restarting higher can slag the motor.

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  8. My father flew B-17G in WW2. He said the plane always experienced "Automatic Rough" when over water and beyond gliding distance to land! These ferry pilots are brave souls and worth every dollar that they charge in fees. Engine failure with turboprops is quite rare. Wonder if the fuel was contaminated?

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  9. Report makes it sound like the add-in ferry fuel design and/or procedure was flawed or not verified. Expensive test flight, lost the test bed airframe.

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  10. Flying the North Pacific, FALL 2105 POPA MAGAZINE
    "The distance from Santa Barbara to Honolulu is 2,160 nm and, even if you depart from farther north (say Monterey or Oakland) and aim for Hilo, the closest point of land in Hawaii, the distance is still just over 2,000 nm with not even a rock in between. at’s well beyond the scope of most corporate turboprops and light jets.
    The normal second leg, from Honolulu to Majuro, Marshall Islands, is also 2,000 nm. If you’re headed for Japan or the Philippines, the third leg to Guam is about 1,600 nm, though there are a few airports along the route. If
    you’re destination is Australia, you can route farther south through Christmas Island, Kiribati and on to Pago Pago, American Samoa. Each of those legs is about 1,200 miles. It’s apparent that the Far East is pretty much out
    of reach for most General Aviation aircra without ferry tanks."

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  11. Likely a dumb question, but the plane was manufactured in Stans, Switzerland. Why not fly East and forgo the need for ferry tanks altogether?

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    Replies

    1. maybe it is the multiple nation overflights and stops !
      " pick up and ferry Simon’s aircraft VH-TCP to Australia via Crete, Egypt, Oman, India, Thailand, Vietnam, Bali, Broome and Adelaide: a total of 49 hours flying."

      Delete
    2. Finishing center is in Colorado

      Delete