Sunday, August 11, 2019

Loss of Engine Power (Partial): Beech A36, N48TZ; accident occurred August 17, 2017 near Louisiana Regional Airport (KREG), Gonzales, Ascension Parish, Louisiana

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

Additional Participating Entities:

Federal Aviation Administration / Flight Standards District Office; Baton Rouge, Louisiana
Continental Motors; Mobile, Alabama 
Aviation Accident Final Report - National Transportation Safety Board:

Investigation Docket - National Transportation Safety Board: 

Aviation Accident Data Summary - National Transportation Safety Board:

Location: Gonzales, LA
Accident Number: CEN17LA328
Date & Time: 08/17/2017, 0927 CDT
Registration: N48TZ
Aircraft: BEECH A36
Aircraft Damage: Substantial
Defining Event: Loss of engine power (partial)
Injuries: 2 None
Flight Conducted Under: Part 91: General Aviation - Instructional 


During the initial climb on an instructional flight, the private pilot and instructor noticed a partial loss of engine power. The pilot performed a forced landing into a hay field and the airplane nosed over. Following the accident, the mechanic who normally performed maintenance removed and discarded all twelve spark plugs, as several were worn. A subsequent examination and test run of the engine revealed a leaking fuel hose due to a loose B-nut. The loss of engine power was consistent with an inadequate fuel supply due to a fuel line leak. Further, it is likely that the worn spark plugs would also have contributed to the loss of engine power. 

Probable Cause and Findings

The National Transportation Safety Board determines the probable cause(s) of this accident to be:
A partial loss of engine power due to inadequate maintenance, including worn spark plugs and a leaking fuel hose fitting. 


Engine (reciprocating) - Incorrect service/maintenance (Cause)
Spark plugs/igniters - Fatigue/wear/corrosion (Cause)
Fuel system - Damaged/degraded (Cause)

Personnel issues
Maintenance - Maintenance personnel (Cause)

Factual Information 

On August 17, 2017, about 0927 central daylight time, a Beech A36 airplane, N48TZ, was substantially damaged during a forced landing after departing from the Louisiana Regional Airport (REG), Gonzales, Louisiana. The pilot and flight instructor were not injured. The airplane was registered to and operated by Gulf Central Aviation LLC under the provisions of Title 14 Code of Federal Regulations Part 91 as an instructional flight. Day visual meteorological conditions prevailed for the local flight, which departed without a flight plan about 0926.

According to the pilot, he departed from Runway 17, following a normal engine run up and takeoff roll. After reaching about 150 ft agl, the pilot noticed the airplane was no longer climbing and lowered the airplane's nose. Based on his perceptions of a partial engine power loss, the pilot checked the throttle and mixture lever positions, both of which were full forward. After maneuvering to avoid trees, the pilot initiated a forced landing into a hay field. During the landing roll, the airplane impacted a small ridge and nosed over, which damaged the engine firewall.

Examination at the recovery location revealed the ignition harness connecting the magnetos to each of the top sparkplugs had been disconnected from the sparkplugs. All twelve sparkplugs appeared new, with no combustion deposits noted. Without authorization, a mechanic who normally performed maintenance on the airplane stated he had removed and discarded the spark plugs due to several having a worn-out condition. Not realizing the airplane should not be disturbed during the investigation, the mechanic had also removed the fuel screen.

Examination of the throttle and mixture control cables revealed proper attachment to their respective control arms. Borescope inspection of piston domes, cylinder wall surfaces, and intake and exhaust valves revealed normal wear patterns and combustion signatures, except for the No. 5 cylinder exhaust valve, which had a green crescent-shaped discoloration on the bottom of the valve face.

After the fuel screen was returned by the mechanic, an engine test run was performed. The engine rotated and ran on the first attempt but stopped after several seconds. A fuel leak was observed adjacent to the fuel pump, with a flexible fuel hose leaking at a B-nut. The nut was tightened about ¼ turn, which seated the nut onto the fitting. The engine driven fuel pump and the adjacent oil filter adapter were stained with a blue color.

A second fuel leak was observed at the throttle body/metering unit, with the fuel mixture arm and shaft bent in a manner consistent with impact damage. A second engine test run was conducted, during which power was not increased above 1,100 rpm, due to a damaged propeller. The engine was operated at varying speeds and a magneto check was accomplished, with no anomalies. The throttle was reduced to idle power and the engine ran smoothly.

The oil on the oil rod was very dark in color. A logbook review revealed the engine had accumulated 163.7 hours since the last oil and oil filter change. The manufacturer recommends oil change intervals of 50 hours for an engine equipped with external filters installed.

History of Flight

Initial climb
Loss of engine power (partial) (Defining event)

Hard landing

Pilot Information

Certificate: Private
Age: 43, Male
Airplane Rating(s): Single-engine Land
Seat Occupied: Left
Other Aircraft Rating(s): None
Restraint Used: 3-point
Instrument Rating(s): None
Second Pilot Present: Yes
Instructor Rating(s): None
Toxicology Performed: No
Medical Certification: Class 3 Without Waivers/Limitations
Last FAA Medical Exam: 08/28/2017
Occupational Pilot: No
Last Flight Review or Equivalent: 09/19/2016
Flight Time:  302 hours (Total, all aircraft), 165 hours (Total, this make and model), 148 hours (Pilot In Command, all aircraft), 18 hours (Last 90 days, all aircraft), 11 hours (Last 30 days, all aircraft), 3 hours (Last 24 hours, all aircraft)

Flight Instructor Information

Certificate: Airline Transport; Flight Instructor
Age: 58, Male
Airplane Rating(s): Multi-engine Land; Single-engine Land
Seat Occupied: Right
Other Aircraft Rating(s): None
Restraint Used: 3-point
Instrument Rating(s): Airplane
Second Pilot Present: Yes
Instructor Rating(s): Airplane Single-engine; Instrument Airplane
Toxicology Performed: No
Medical Certification: Class 2 With Waivers/Limitations
Last FAA Medical Exam: 02/21/2017
Occupational Pilot: Yes
Last Flight Review or Equivalent: 05/12/2017
Flight Time:  (Estimated) 18100 hours (Total, all aircraft), 3000 hours (Total, this make and model), 17200 hours (Pilot In Command, all aircraft), 100 hours (Last 90 days, all aircraft), 25 hours (Last 30 days, all aircraft), 0 hours (Last 24 hours, all aircraft)

Aircraft and Owner/Operator Information

Aircraft Make: BEECH
Registration: N48TZ
Model/Series: A36
Aircraft Category: Airplane
Year of Manufacture: 1980
Amateur Built: No
Airworthiness Certificate: Normal
Serial Number: E-1804
Landing Gear Type: Retractable - Tricycle
Seats: 6
Date/Type of Last Inspection: 08/08/2016, Annual
Certified Max Gross Wt.: 3651 lbs
Time Since Last Inspection: 163 Hours
Engines: 1 Reciprocating
Airframe Total Time: 6184 Hours at time of accident
Engine Manufacturer: Continental
ELT: Installed, not activated
Engine Model/Series: IO-520
Rated Power: 285 hp
Operating Certificate(s) Held: None 

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual Conditions
Condition of Light: Day
Observation Facility, Elevation: KREG, 14 ft msl
Distance from Accident Site: 1 Nautical Miles
Observation Time: 0935 CDT
Direction from Accident Site: 17°
Lowest Cloud Condition: Scattered / 300 ft agl
Visibility: 10 Miles
Lowest Ceiling:
Visibility (RVR):
Wind Speed/Gusts: 6 knots /
Turbulence Type Forecast/Actual: None / None
Wind Direction: 230°
Turbulence Severity Forecast/Actual: N/A / N/A
Altimeter Setting: 30.09 inches Hg
Temperature/Dew Point: 30°C / 26°C
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: GONZALES, LA (REG)
Type of Flight Plan Filed: None
Destination: GONZALES, LA (REG)
Type of Clearance: None
Departure Time: 0926 CDT
Type of Airspace: Class G

Airport Information

Runway Surface Type: Asphalt
Airport Elevation: 14 ft
Runway Surface Condition: Dry
Runway Used: 17
IFR Approach: None
Runway Length/Width: 5003 ft / 100 ft
VFR Approach/Landing: Forced Landing

Wreckage and Impact Information

Crew Injuries: 2 None
Aircraft Damage: Substantial
Passenger Injuries: N/A
Aircraft Fire: None
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 2 None
Latitude, Longitude: 30.153889, -90.937778 (est)


  1. Sounds like a cover up to me.

  2. ^^^^^ Agree

    Sounds like he knew exactly what he hadn't bothered with ... Except the B nuts and the oil change.

    I do wonder if there will be certificate action. It would be justified in a case like this.

    Good job on the part of the pilot.

  3. So the mechanic went in there and immediately tried to cover it up. SMH

    This is the reason why I am getting my A&P soon. There is absolutely 0 justification for a pilot to not also become an airplane mechanic, especially if they can get an LSRM and prove 30 months of work after (it doesn't have to be full time btw). Or work under an A&P who signs off their mechanics logbook then go to the FSDO to get the authorization to do the exams a few years after.

    It's all a continuous process to learn right and airplanes are very primitive and rugged, for a reason.

    Those puppy mills mechanic schools try to always scare you with "thousands of hours" of requirements but the specs all for "months" of work not hours.

    Ironically this was done because some FAA inspectors who were A&Ps needed to maintain currency so the "monthly" requirement can cover as little as a few hours worth of work per month.

    Now since my ass will be in that plane you can betcha I will do a top notch job. No need to delegate it to some car mechanic "under supervision" from 1 single solitary A&P in a repair shop.

  4. I would guess that others who use the "mechanic" should have their planes attended to by someone else.

    Depending on the relationship with the FSDO, the "mechanic" may have his day in front of the Federales .

  5. You cannot skip anything in aviation,do so at your peril,and when you rely on another party to maintain your aeroplane then it has to be done right.
    A&P is not the end,its a name given to someone who should be responsible but that person does not need to be passionate about aviation or even the machine they are working on,it does not make you a knowledgeable engineer that takes time learning constantly.
    The demand is there but sadly the quality is declining witness accidents like this,we have more aircraft flying than good engineers can cope with,pushing through the maintenance schools is not the answer,that is about money.
    What we need are basic courses as a starter for pilots who want to know more about aircraft maintenance and to build on their knowledge gradually,to take a pride in everything to do with their machine.
    If someone signs off work done then that work needs to have been done ! properly no question.