ERA14FA350

NTSB accident investigation · Wilderoder Great Lakes 2TIA · Lillian, AL · July 23, 2014

Accident · FatalField investigationFinal report
Date
July 23, 2014, 10:20 local (15:20 UTC)
Place
Lillian, AL
Injuries
2 fatal
Damage
Substantial damage
Phase of flight
Maneuvering
Aircraft
N47149Wilderoder Great Lakes 2TIA
Defining event
Maneuvering-low-alt flying: Loss of engine power (total)
Weather
Visual (VMC) · Day
Status
Completed · report September 29, 2015
Report
Approved by Office Director
NTSB office
Eastern Region Aviation
Parties
FAA/FSDO, Lycoming Engines
FAA report
20140723014889A
Case key
89725

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

On this page

Probable cause

A loss of engine power due to an inoperative magneto and possible carburetor ice, which resulted in a forced landing into unsuitable terrain. Contributing to the accident was an inadequate magneto overhaul by unknown personnel and the modification to the carburetor heat system.

Findings · 5

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Temp/humidity/pressure: conducive to carburetor icingEnvironmental issues › Conditions/weather/phenomena · Not specifiedWilderoder GREAT LAKES 2TIA: 1 caseAll aircraft: 435 casesProbable cause
Maintenance: repairPersonnel issues › Task performance · Maintenance personnelWilderoder GREAT LAKES 2TIA: 1 caseAll aircraft: 99 casesProbable cause
Maintenance: modification/alterationPersonnel issues › Task performance · Maintenance personnelWilderoder GREAT LAKES 2TIA: 1 caseAll aircraft: 69 casesProbable cause
Terrain: rough terrainEnvironmental issues › Physical environment · Not specifiedWilderoder GREAT LAKES 2TIA: 1 caseAll aircraft: 442 cases

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

The pilot of the experimental, amateur-built airplane completed one 15-minute local flight with a passenger onboard. During a second 15-minute local flight with a different passenger, two witnesses near the accident site observed the airplane flying about 500 ft above ground level. They did not notice anything unusual about the flight and diverted their attention. The airplane was subsequently reported overdue and located about 6 hours later. The airplane impacted wooded swampy terrain in a level attitude on a heading consistent with the closest airport. A strong smell of fuel at the accident site indicated the presence of fuel at impact. There was no evidence of pilot incapacitation. Examination of the wreckage did not reveal any preimpact mechanical malfunctions with the exception of the left magneto, which would not produce spark. Although records indicated the magnetos were overhauled within 2 years of the accident, laboratory examination of the left magneto revealed that its internal components were worn and near their life limit, which was not consistent with an overhaul during the previous 2 years. The points also did not make contact when closed. The investigation was unable to determine if the pilot performed a preflight check of the magnetos before departing on the accident flight or the preceding flight. Additionally, the mechanic who maintained the airplane stated that about 6 months before the accident, the left exhaust manifold was sent out for repair due to cracking. To prevent further cracking, the repair facility installed ball joints; however, the carburetor heat shroud had to be reduced by about half-size to facilitate the modification. The reduced carburetor heat shroud would have resulted in a corresponding reduction in carburetor heat capability. A review of a carburetor icing chart revealed that, for the given temperature and dew point, atmospheric conditions were conducive to the formation of "serious icing" at engine glide power settings. The previous passenger reported that part of the scenic flight included a reduction in engine power to idle and a gliding descent. The carburetor heat control was found in the "ON" position. It was likely that an inoperative magneto and possible carburetor ice accumulated while gliding that the carburetor heat system was unable to melt resulted in a loss of engine power and forced landing into the swamp.

Factual narrative

The two-seat tandem, bi-wing, tailwheel airplane, serial number 7115-J521, was assembled in 1978 and issued an FAA experimental airworthiness certificate. It was powered by a Lycoming O-320, 150-horsepower engine, equipped with a two-blade, fixed-pitch, McCauley propeller. The pilot purchased the airplane with a partner in 1988. According to the aircraft logbooks, the airplane's most recent annual condition inspection was completed on March 15, 2014. At that time, the airplane had accumulated 682.97 total hours of operation and the engine had accumulated 1404.08 hours since major overhaul. According to the tachometer, the airplane flew 8.25 hours from the time of the condition inspection, until the accident. Additionally, review of the engine logbook revealed that two overhauled magnetos were installed on February 11, 2013; however, the investigation was unable to determine where the magnetos were overhauled. The mechanic who maintained the airplane stated that in January 2014, the left exhaust manifold was sent for repair due to cracking. To prevent further cracking, the repair facility installed ball-joints; however, the carburetor heat shroud had to be reduced by about half-size to facilitate the modification. On July 23, 2014, about 1020 central daylight time, an experimental, amateur-built Great Lakes 2T1A, N47149, operated by a private individual, was substantially damaged when it impacted a swamp near Lillian, Alabama. The private pilot and passenger were fatally injured. The local personal flight was conducted under the provisions of Title 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed and no flight plan was filed for the flight that departed Ferguson Airport (82J), Pensacola, Florida, about 1010. The pilot owned the airplane and based it at 82J. Prior to the accident flight, he had completed a 15-minute personal scenic flight uneventfully with a different passenger. That passenger then deplaned and the pilot boarded another passenger for another 15-minute local flight. When the airplane did not return, search and rescue procedures were initiated. An Alabama State Police helicopter tracked the pilot's mobile phone and located the wreckage about 1600, in swampy terrain approximately 5 miles northwest of 82J. The airplane was not, nor was it required to be, equipped with a transponder. Review of radar data from the Federal Aviation Administration (FAA) revealed primary radar targets recorded near 82J about the time of the accident. The targets were consistent with a departure on runway 18, followed by a left downwind leg departure from the airport traffic pattern and a left turn to the west. After a westerly track that continued for about 4 miles, there was an approximate 1-mile gap in data, followed by five targets recorded on a northerly track near the accident site. Two witnesses, who were at a residence near the accident site, reported seeing a biplane, consistent with the accident airplane, shortlyafter 1000. The airplane seemed low, below a cloud layer about 500 feet above ground level. It performed steep turns to reverse direction, but did not make any unusual maneuvers, or appear to be in distress. Both witnesses lived near a local airport, saw airplanes frequently, and paid no more attention to the airplane. They did not witness the accident. According to the father of the previous passenger, the previous flight was unremarkable and no aerobatics were performed. His son recalled that the pilot reduced the engine power to idle and let the airplane glide for a while, which the son enjoyed. An autopsy was performed on the pilot on July 25, 2014, by the Alabama Department of Forensic Sciences, Huntsville, Alabama. The cause of death was reported as "blunt force injuries." Toxicological testing on the pilot was performed by the FAA's Civil Aerospace Medical Institute, Oklahoma City, Oklahoma. All test results were negative for drugs and alcohol. Pensacola International Airport (PNS), Pensacola, Florida was located about 13 miles east of the accident site. The recorded weather at PNS, at 1053, was: wind from 110 degrees at 6 knots; visibility 10 miles; scattered clouds at 2,000 feet; temperature 28 degrees Celsius; dew point 22 degrees Celsius; altimeter 30.06 inches of mercury. Review of an FAA Carburetor Icing chart, for the given temperature and dewpoint, revealed that the weather conditions were conducive to the formation of "Serious Icing" at glide engine power settings. The pilot held a private pilot certificate with a rating for airplane single-engine land. His most recent FAA third-class medical certificate was issued on October 9, 2012. At that time, he reported a total flight experience of 700 hours. Review of excerpts from the pilot's logbook revealed that he had flown 3 hours and 2 hours, all in the accident airplane, during the 90-day and 30-day period preceding the accident, respectively. Due to the terrain, the investigative team could not safely access the wreckage at the accident site. The wreckage was subsequently examined at a salvage facility following its recovery. One of the recovery personnel stated that tree damage at the accident site was consistent with a level attitude on a westbound heading. He also noted a strong smell of fuel at the accident site. The examination revealed that the rudder remained attached to the empennage and the stabilator had separated. The elevator remained attached to the stabilator. The right elevator had a fixed trim tab and the stabilator was equipped with a manual trim control system. Continuity was confirmed from the rudder, elevator attach point, and stabilator trim jackscrew to the rear cockpit area where the cables were cut by recovery personnel. The airplane was equipped with upper and lower ailerons and was not equipped with flaps. The lower ailerons were controlled via push-pull tubes from the cockpit and connected to the upper ailerons. The fuel tank located at the center of theupper wing was compromised. The fuel sump contained water, but the wreckage had been submerged in approximately 2 feet of water prior to recovery. The cockpit remained intact. The mixture and throttle levers were in the full forward position and the fuel valve was on. The carburetor heat control was in the rear (on) position. The magnetos switch was selected to the "both" position and the primer was in and locked. The fuel boost pump was off. The elevator trim indicator displayed full nose up; however, the preimpact trim indicator position could not be determined. An emergency locator transmitter was not recovered. The spark plugs and valve covers were removed from the engine. The top spark plug electrodes were intact. The No. 1 top spark plug electrode was lead fouled. The No. 4 bottom spark plug contained sediment. The carburetor was also removed. Its float and needle were intact. The carburetor fuel screen was absent of debris. The valve was in the full open position and could be actuated by hand. One propeller blade was bent aft and the other exhibited a slight s-bend. The oil filer was also absent of debris. When the propeller was rotated by hand, camshaft, crankshaft, and valve train continuity were confirmed and thumb compression was attained on all cylinders. There was no evidence that the magnetos were submerged in water. According to the data plate and company records, the right magneto (Part No. 51360-29, Serial No. 342061) was remanufactured at the Bendix factory in 1973. When the shaft was rotated via an electric drill, the right magneto produced spark at all leads. The left magneto (Part No. 51360-30, Serial No. 980196 was manufactured at the Bendix factory in 1968. When the shaft was rotated via an electric drill, the left magneto did not produce any spark. It was subsequently forwarded to the NTSB Materials Laboratory, Washington, D.C., for further examination. The Bendix factory did not perform overhauls of magnetos and the investigation could not determine how many field overhauls of the magnetos occurred during their approximate 40-year life. Metallurgical examination of the left magneto revealed that the points did not make electrical contact when closed. The carbon electrodes and gear electrode exhibited heavy deposits and erosion, consistent with extended age and operation. Additionally, the points, distributor and brushes appeared to be at the end of their useful life and not consistent with a magneto that was recently overhauled (for more information see Materials Laboratory Factual Report in the NTSB Public Docket).

Aircraft

Registration
N47149
Reported as
Wilderoder Great Lakes 2TIA
Category
Airplane, amateur-built
Serial number
7115-J521
Built
1978
Airframe hours
683
Engine
Lycoming O-320, 150 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Operator
Dean J Legidakes Sr
Registered owner
Presnell Lawrence D
Airworthiness certificate
Special, Experimental (Special)
Last inspection
Condition · March 15, 2014 · 8 hours before
Departed
82J · Pensacola, FL
Destination
82J · Pensacola, FL

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
67
Injuries
Fatal
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 3, With waivers/limitations
Seat
Rear
Restraint
5-point
Toxicology
Performed
Flight hours
700 total · 999,999 in this make and model · 3 in the last 90 days · 2 in the last 30 days

Weather

Conditions
Visual (VMC) · Day
Wind
110° at 6 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
82 °F, dew point 72 °F
Altimeter
30.05 inHg
Observed at
PNS, 13 nm away

Docket · 18

The files NTSB released with the investigation on September 24, 2015, on NTSB’s docket system: statements, records, photos and specialists’ reports. 7.6 MB in all.

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.

Other investigations on N47149 · 1

Matched to the same aircraft by N-number and date.