IAD02FA074

NTSB accident investigation · Wehrlen Glassair II RG · Jackson, NJ · July 20, 2002

Accident · FatalField investigationFinal report
Date
July 20, 2002, 13:45 local (17:45 UTC)
Place
Jackson, NJ
Injuries
1 fatal
Damage
Destroyed
Phase of flight
Maneuvering
Aircraft
N79CWWehrlen Glassair II RG
Weather
Visual (VMC) · Day
Status
Completed · report November 25, 2003
Report
Approved by Office Director
Parties
Textron-Lycoming Engines, FAA/FSDO
FAA report
20020720038619A
Case key
55255

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

The pilot's failure to maintain airspeed, which resulted in an inadvertent stall/spin and subsequent impact with terrain.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

Loss of control - in flightManeuvering
Airspeed - not maintainedPilot in commandCause
Stall/spin - inadvertentPilot in command
In flight collision with terrain/waterDescent - uncontrolled

Analysis

The airplane was observed flying "kind of low" before it spiraled "straight down." It completed three rotations before impacting trees. Post-accident examination revealed no mechanical anomalies. The pilot's operating handbook stated that due to the many variables that affect spin recovery, and the lack of control over those variables, intentional spins were prohibited.

Factual narrative

History of flight

On July 20, 2002, about 1345 eastern daylight time, a homebuilt Glassair II RG, N79CW, was destroyed when it collided with terrain in Jackson, New Jersey. The certificated private pilot was fatally injured. Visual meteorological conditions prevailed, and no flight plan was filed for the personal flight conducted under 14 CFR Part 91.

A witness, who was working in his backyard, first noticed the airplane when it was about 400 feet above the tree line. The airplane was "spiraling straight down," and completed three rotations before it impacted the trees. The witness described the rotations as "similar to tricks you would see in an air show." According to the witness, the engine was running at a "steady, normal" speed.

A second witness was sitting in her backyard about 300 yards from the accident site. She said that her brother pointed out the airplane to her, and commented that it was "flying kind of low." The airplane then started to "spiral downwards," and looked like it was "doing some tricks." The witnesses said it appeared the pilot had attempted to "pull the plane up," just before it impacted the trees.

A Safety Board Air Traffic Control (ATC) Specialist examined radar data provided by the Federal Aviation Administration (FAA), and identified a target flying in the vicinity of the accident side at the time of the accident.

The target was first observed at 1341 at an altitude of 1,700 feet, approaching the Jackson area from the north. For the next 4 minutes, the target continued on a track of 140 degrees and maintained an altitude of 1,600-1,700 feet. The last radar contact was observed at 1745, about 3 miles to the northwest of the accident site, at an altitude of 1,700 feet.

The accident occurred during the hours of daylight, approximately 40 degrees, 03 minutes north latitude, and 74 degrees, 16 minutes west longitude.

Personnel information

The pilot's logbook was not located. However, a review of FAA records revealed 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 April 30, 2002. At that time, he reported 800 hours of total flight experience.

Aircraft information

Examination of fuel records provided by the fixed base operator (FBO) at the Lakewood Airport (N12), Lakewood, New Jersey, revealed that the airplane was refueled on the day of the accident, at 1230, with 24 gallons of 100LL aviation fuel. A sample of fuel from the fuel tanks at the FBO was examined, and revealed no anomalies.

A review of the airplane logbook revealed that the airplane received its last annual inspection on May 1, 2002, at a tachometer time of 238.2. The tachometer time at the accident site was 249.4.

Meteorological information

The weather reported at McGuire Air Force Base, about 17 miles west of the accident site, at 1355, included winds from 340 degrees at 7 knots, 6 miles visibility with haze, scattered clouds at 5,000 feet, broken clouds at 20,000 feet, temperature 82 degrees F, dew point 64 degrees F, and a barometric pressure of 29.98 inches Hg.

Communications

A survey of air traffic control facilities revealed no communications with the pilot on the day of the accident.

Wreckage and impact information

The airplane was examined at the accident site on July 20-21, 2002. All major components of the airplane were accounted for at the scene. The airplane came to rest on an approximate heading of 220 degrees, at an elevation of 81 feet msl.

Initial tree impact scars started about 67 feet from the main wreckage, and became progressively lower on the trees in the direction of the main fuselage. The wreckage path was oriented on a heading of 190 degrees.

Observed along the wreckage path were the outboard section of the right wing, right aileron, both wing tank fuel caps, the left aileron, a section of the left flap, and several pieces of the fiberglass wings. Also noted along the wreckage path was a 45-degree angular slash mark in a standing tree, about 4 feet from the main wreckage.

The main wreckage consisted of the fuselage, empennage, engine, and inboard sections of both wings. The empennage was oriented on a heading of 150 degrees, and the fuselage section from the wings forward, had separated from the empennage and was oriented on a heading of 220 degrees.

The vertical stabilizer, rudder, and horizontal stabilizer remained intact and attached to the empennage. Rudder and stabilizer control continuity were established from the control surfaces to the cockpit area.

The inboard 4-foot sections of both wings remained attached to the fuselage at their wing roots, and both main landing gear assemblies were observed in the retracted position. A 3-foot section of the left flap was connected to the inboard section of the wing at its inboard hinge. The 5-foot outboard section of the left wing was separated, and resting adjacent to the inboard section. Reddish-brown transfer marks and concave dents were noted along the leading edge of this section.

The right flap was observed connected to the inboard section of the right wing, at its inboard hinge.

Aileron control continuity was established from the control column to the outboard separation points of the control rods.

The engine remained attached to the airplane and the propeller had separated from the engine. Both propeller blades displayed chordwise scratching and leading edge gauges on the blade tips. The engine starter ring gear and the engine starter nose housing displayed rotational scoring. The header fuel tank located in the engine cowling was compromised; however, the fuel cap was secured to the cowling. Approximately 1 pint of liquid similar to aviation fuel was drained from the gascolator, and was absent of debris. In addition, examination of the soil underneath the engine revealed it was saturated, and a strong odor of aviation fuel was noted.

On July 22, 2002, the engine was examined at a salvage facility, under the supervision of the Safety Board. The examination revealed that when the engine was rotated by hand through the accessory section, valvetrain continuity was established to the propeller flange. Compression was confirmed on each cylinder using the thumb method.

During manual rotation of the engine, the left magneto was tested, and produced spark on all terminal leads. The right magneto was removed from the engine and rotated by hand. Spark was produced on all terminal leads.

The spark plugs were removed from the engine and visual examination revealed their electrodes were intact, and light gray in color.

Borescope examination of the cylinders, pistons, and valves revealed no mechanical deficiencies or anomalies.

Fuel was observed in the fuel lines, gascolator, carburetor, and engine driven fuel pump.

Medical and pathological information

An autopsy was performed on the pilot, on July 22, 2002, at the Kimball Medical Center, Lakewood, New Jersey.

Toxicological testing was performed by the FAA Toxicology Accident Research Laboratory, Oklahoma City, Oklahoma.

Additional information

According to an excerpt from the LIMITATIONS Section of the Glassair Pilot's Operating Handbook:

"Due to many variables that affect spin recovery, and our lack of control over these variables, we prohibit the Glassair from intentional spins."

The airplane wreckage was released on July 23, 2002, to a representative of the pilot's insurance company.

Aircraft

Registration
N79CW
Reported as
Wehrlen Glassair II RG
Category
Airplane, amateur-built
Serial number
1
Airframe hours
249
Engine
Lycoming O-320, 180 horsepower, reciprocating
Damage
Destroyed
Flight
Personal · Part 91
Registered owner
Russell Terhune
Airworthiness certificate
Special, Experimental (Special)
Last inspection
Annual · May 1, 2002 · 11 hours before
Departed
N12 · Lakewood, NJ
Destination
N12
Airport
N12 · Lakewood airport

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
49
Injuries
Fatal
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 3, Valid Medical--w/ waivers/lim
Seat
Left
Toxicology
Performed
Flight hours
800 total

Weather

Conditions
Visual (VMC) · Day
Wind
340° at 7 knots
Visibility
6 statute miles
Lowest ceiling
20,000 ft broken
Temperature
82 °F, dew point 64 °F
Altimeter
29.97 inHg
Observed at
WRI, 17 nm away

Docket · 9

The files NTSB released with the investigation on August 20, 2003, on NTSB’s docket system: statements, records, photos and specialists’ reports. 3.5 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.