Sunday, June 21, 2020

Electrical System Malfunction/Failure: Beech E-90 King Air, N891PC; accident occurred August 28, 2015 near Fayetteville Municipal Airport (KFYM), Lincoln County, Tennessee












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

Additional Participating Entity:
Federal Aviation Administration / Flight Standards District Office;  Nashville, Tennessee

Aviation Accident Factual Report - National Transportation Safety Board:  https://app.ntsb.gov/pdf

Investigation Docket - National Transportation Safety Board: https://dms.ntsb.gov/pubdms

https://registry.faa.gov/N891PC

Location: Fayetteville, TN
Accident Number: ERA15LA333
Date & Time: 08/28/2015, 1400 CDT
Registration: N891PC
Aircraft: BEECH E 90
Aircraft Damage: Substantial
Defining Event: Electrical system malf/failure
Injuries: 1 None
Flight Conducted Under: Part 91: General Aviation - Personal

On August 28, 2015 about 1400 central daylight time, a Beechcraft E-90, N891PC, was substantially damaged during an off-airport landing near Fayetteville, Tennessee. The private pilot was not injured. The airplane was registered to Chopaire LLC and operated under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual flight rules conditions prevailed about the time of the accident, and no flight plan was filed for the flight that departed from Shelbyville Municipal Airport (SYI), Shelbyville, Tennessee, and was destined for Huntsville International Airport (HSV), Huntsville, Alabama.

The pilot reported that the start-up, taxi and takeoff were normal. He had about 270 gallons of fuel on board for the 65-mile flight to HSV. Several minutes after takeoff, while climbing through 3,000 feet in visual meteorological conditions, a total electrical failure occurred. He reported that he performed the generator inoperative emergency checklist but was unable to restore electrical power. He did not see the GEN OUT annunciator light. He further reported that he turned all the switches off to shed any load, then turned on the battery switch followed by the generator switches, but he could not restore power. Without any electrical power and no communication ability, he diverted to Fayetteville Municipal Airport (FYM), Fayetteville, Tennessee, approximately 30 miles south of SYI.

After arriving in the airport traffic pattern at FYM, a public use airport that had a 5,900-ft-long by 100-ft-wide paved and lighted runway that was oriented 02/20, he attempted to lower the landing gear using the emergency gear extension procedures, but reported, "I did not believe that the landing gear was extending. I did not feel any resistance in the manual extension handle." Without electrical power, the green landing gear lights did not function. He discontinued pumping the handle and decided that without any communications capability or confirmation that the gear was down and locked, he would land off-airport to avoid airport traffic. He departed the FYM traffic pattern and found an open field that looked suitable; the airplane touched down in waist-high soybeans and soft ground and came to an abrupt stop within several hundred feet.

According to the pilot and Federal Aviation Administration (FAA) records, the pilot, age 62, held a private pilot certificate with ratings for airplane single-engine land, airplane multi-engine land, and instrument airplane. He reported 1,882 hours of total flight time, with 230 hours of accident airplane make and model. His most recent flight review was conducted on August 8, 2015 in the accident airplane make and model. This was the pilot/owner's second flight in this make/model without an instructor in the right seat. According to a witness, it was highly unusual that the pilot was not flying with a safety pilot, who was usually his instructor.

Postaccident examination of the wreckage revealed substantial damage to the fuselage, landing gear doors, engines, and propellers.

According to FAA records, the airplane was manufactured in 1973. It was an 8-seat, low wing, twin turboprop airplane equipped with Pratt & Whitney PT6-28 engines each rated at 680 horsepower and each engine was equipped with four-blade Hartzell propellers. The left and right engines had 6,255 and 12,471 total hours respectively and the airplane had accumulated 11,283 total airframe hours since its most recent annual inspection on June 4, 2015.

The airplane was equipped with a 24-volt, 45 ampere-hour battery which provided current for starting and electrical loads. At full charge, the battery would last for about 30 minutes. There were two starter generators, and when used as a generator, each one would provide continuous electrical power to the airplane at a capacity of 250 amperes each at 28.25 volts. The pilot reported that he ran the electrical system failure checklist after he lost all electrical power; this included turning off the generator then back on to reset. No additional troubleshooting procedures reported by the pilot could restore electrical power.

The landing gear extension mechanism was electrically driven and mechanically-actuated with a chain-driven motor, and would not extend normally without electrical power. In addition, the three green landing gear lights indicating that the landing gear was down and locked would not function during power loss, so an emergency landing gear extension procedure must be followed.

According to the King Air E-90 Airplane Flight Manual (AFM), the procedure to manually lower the landing gear was to establish 120 knots indicated airspeed, pull the landing gear circuit breaker, place the landing gear handle in the down position, lift the "J" handle and turn it 50° clockwise to engage the clutch, then pump the extension lever up and down until 3 green lights are acquired; which will not occur due to no electrical power to the system. There were no indications in the manual or procedures as to how many pumps of the handle will extend and lock the landing gear.

A postaccident examination of the cockpit, the "J" handle that engaged the landing gear pump was not pulled up or turned; it remained in the stowed position. Pumping the gear extension handle without the "J" handle would not lower the gear and it would not provide any feedback to the operator.

At 1415, the weather recorded at FYM, located 8 miles southeast of the accident site, included scattered clouds at 3,900 ft, wind from 160° at 4 knots, and visibility 10 statute miles. The temperature was 29°C, and the dew point was 15°C. The altimeter setting was 30.09 inches of mercury. 

Pilot Information

Certificate: Private
Age: 62, Male
Airplane Rating(s): Multi-engine Land; Single-engine Land
Seat Occupied: Left
Other Aircraft Rating(s): None
Restraint Used: 4-point
Instrument Rating(s): Airplane
Second Pilot Present: No
Instructor Rating(s): None
Toxicology Performed: No
Medical Certification: Class 3 Without Waivers/Limitations
Last FAA Medical Exam: 07/23/2015
Occupational Pilot: No
Last Flight Review or Equivalent: 08/08/2015
Flight Time:  1882 hours (Total, all aircraft), 230 hours (Total, this make and model), 1310 hours (Pilot In Command, all aircraft), 16 hours (Last 90 days, all aircraft), 10 hours (Last 30 days, all aircraft), 1 hours (Last 24 hours, all aircraft)

Aircraft and Owner/Operator Information

Aircraft Make: BEECH
Registration: N891PC
Model/Series: E 90 NO SERIES
Aircraft Category: Airplane
Year of Manufacture:
Amateur Built: No
Airworthiness Certificate: Normal
Serial Number: LW-40
Landing Gear Type: Retractable - Tricycle
Seats: 8
Date/Type of Last Inspection: 06/04/2015, Annual
Certified Max Gross Wt.: 10099 lbs
Time Since Last Inspection: 20 Hours
Engines: 2 Turbo Prop
Airframe Total Time: 11283 Hours as of last inspection
Engine Manufacturer: P & W
ELT: C91 installed, not activated
Engine Model/Series: PT6A-28
Registered Owner: CHOPAIRE LLC
Rated Power: 680 hp
Operator: CHOPAIRE LLC
Operating Certificate(s) Held: None

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual Conditions
Condition of Light: Day
Observation Facility, Elevation: KMDQ, 801 ft msl
Distance from Accident Site: 30 Nautical Miles
Observation Time: 1415 CDT
Direction from Accident Site: 170°
Lowest Cloud Condition: Scattered / 3900 ft agl
Visibility:  10 Miles
Lowest Ceiling:
Visibility (RVR):
Wind Speed/Gusts: 4 knots /
Turbulence Type Forecast/Actual: / None
Wind Direction: 160°
Turbulence Severity Forecast/Actual: / Unknown
Altimeter Setting: 30.09 inches Hg
Temperature/Dew Point: 29°C / 15°C
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: SHELBYVILLE, TN (SYI)
Type of Flight Plan Filed: None
Destination: Huntsville, AL (HSV)
Type of Clearance: None
Departure Time: 1300 CDT
Type of Airspace: Class G

Wreckage and Impact Information

Crew Injuries: 1 None
Aircraft Damage: Substantial
Passenger Injuries: N/A
Aircraft Fire: None
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 1 None
Latitude, Longitude: 35.139444, -86.682222

5 comments:

  1. This accident should encourage pilots to put the aircraft on jackstands and practice emergency gear deployment. Do it during annual inspection if not sooner. Not having green lights can be overcome if practice on jackstands determine what is required to reach down and locked.

    No need to crash a still-controllable airplane just because the emergency deployment was never practiced.

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  2. The battery was strong enough to spin up the first PT6, which when running would carry the load and recharge the battery. Either PT6 could power the electrical system once started. No mention of undervoltage before blackout, just the abrupt/total failure.

    Seems odd that no investigation or testing was done to determine what caused the total loss of electrical power. This was an intact aircraft, would have easily supported electrical evaluation.

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  3. I wonder what the starter/generator switches were set to when the loss of electrical power occurred... I'm guessing they were off.

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    Replies
    1. This electrical failure is very similar to the N1551C King Air accident, and the N1551C pilot statement shows both generators were switched on before the total failure. It seems like something common in King Airs that defeats battery connection and drops generator function caused both failures.

      Why was there no cause determination of the N891PC or N1551C King Air electrical failures?

      http://www.kathrynsreport.com/2020/06/electrical-system-malfunctionfailure_21.html

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    2. The accident investigations of N1551C and N891PC are still ongoing, no probable cause has been released.

      N1551C:

      https://app.ntsb.gov/pdfgenerator/ReportGeneratorFile.ashx?EventID=20170307X03418&AKey=1&RType=HTML&IType=LA

      N891PC:

      https://app.ntsb.gov/pdfgenerator/ReportGeneratorFile.ashx?EventID=20150831X33537&AKey=1&RType=HTML&IType=LA

      Delete