NYC94FA028

NTSB accident investigation · Piper PA-31T · Norwich, OH · December 2, 1993

Accident · FatalField investigationFinal report
Date
December 2, 1993, 13:41 local (18:41 UTC)
Place
Norwich, OH
Injuries
2 fatal
Damage
Destroyed
Phase of flight
Enroute
Aircraft
N515WBPiper PA-31T
Weather
Visual (VMC) · Day
Status
Completed · report December 2, 1994
Report
Approved by Office Director
FAA report
19931202045709A
Case key
38662

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

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Probable cause

The pilot's loss of aircraft control for an unknown reason, and subsequent flight that exceeded the design stress limits of the airplane, which resulted in an in-flight airframe breakup.

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 flightCruise - normal
Aircraft control - not maintainedPilot in commandCause
Maintenance,annual inspection - exceeded
Weather condition - turbulence
Airframe/component/system failure/malfunctionDescent - uncontrolled
Design stress limits of aircraft - exceededCause
Stabilizer - overload
Stabilizer - separation
Wing - overload
Wing - separation
Door,cargo/baggage - separation
In flight collision with terrain/waterDescent - uncontrolled

Analysis

En route at FL 240, the plane entered a left spiraling descent & subsequently experienced an inflight break-up at 7000' with separation of outboard wings, tail sections & internal vinyl from the nose baggage door. There was no distress call. Witnesses heard the engines & an explosive sound, then they saw the plane in a spin, trailed by falling debris. Debris was strewn over a distance of about 3.5 mi. Light weight pieces including vinyl from the baggage door, wing skin, & tail skin pieces were among the 1st debris on the wreckage path. Tail sections were found about 2.5 mi from the main wreckage with evidence of overload failure; pieces of the wings were found with evidence of downward/overload sep- aration. No preexisting airframe failure was found that would have led to loss of control, inflight breakup, loss of pressurization or hypoxia. The plane was inactive for about 2 yrs before being purchased 2 months before accident. Last annual inspection was on 6/8/92. Icing was forecast from 9000' to 17,000'MSL; turbulence was forecast below 8000' MSL.

Factual narrative

On December 2, 1993, at about 1341 eastern standard time, a Piper PA-31T, N515WB, piloted by Mr. Michael Stevenson, and registered to Brent's International Inc., separated in flight, and collided with the terrain near Norwich, Ohio. The two pilots were fatally injured, and the airplane was destroyed. Visual meteorological conditions prevailed at the time, and an IFR flight plan had been filed. The flight was being conducted under 14 CFR 91.

The pilot had requested and received an IFR clearance from the Baltimore Terminal Radar Control (TRACON) at 1139, from Easton, Maryland, to Des Moines, Iowa.

At 1332, the pilot radioed Indianapolis Air Route Traffic Control Center (ARTCC), frequency 125.07, "level FL 240" [flight level 24,000 feet MSL].

At 1338:37, the recorded radar data from the FAA Indianapolis Air Route Traffic Control Center (ARTCC) showed N515WB, at FL 240, ground speed 205 knots, and heading 300 degrees. At 1338:43, the data showed that N515WB had climbed 100 feet to FL 241, same speed, and heading 299 degrees.

At 1339:01, the airplane had descended to FL 237, and was in a left turn. The airplane continued in a left descending turn, through the following times and altitudes: at 1339:13, FL 217; at 1339:31, 14,400 feet; at 1339:43, 11,600; at 1340:01, 3,900 feet, and the last altitude depicted was 2,100 feet at 1340.19.

The airplane had descended from FL 241 to 2,100 feet, the last altitude depicted on radar, in an elapsed time of 84 seconds. The average vertical speed was approximately 15,714 feet per minute.

Witnesses in the area of the crash site said they heard the airplane's engines revving, followed by explosive sounds. The airplane was seen descending under the clouds in a flat spin, followed by many pieces of debris. The airplane impacted the ground inverted and the wreckage was scattered over an area of approximately 3.5 miles.

The accident occurred during the hours of daylight approximately 39 degrees, 59 minutes north, and 83 degrees, 12 minutes west.

Personnel information

Mr. Michael Stevenson held Airline Transport Pilot Certificate, No. 1730904, with airplane mutiengine and airplane single engine land and sea, instrument airplane ratings.

Mr. Stevenson was issued a Second Class Airman Medical Certificate on October 6, 1993, with limitations, must wear corrective lenses.

Mr. Stevenson's records showing his total flight hours were not located. It was estimated from information provided by the FAA that he had a total of 5,200 flight hours. A friend of Mr. Stevenson told the Safety Board that he had approximately 3 hours of flight time in Piper PA-31T aircraft.

Mr. James E. Templeton held a Commercial Pilot Certificate, No. 1500875, with a single and mutiengine engine land and sea, instrument airplane ratings. Mr. Templeton was issued a Second Class Airman Medical Certificate on November 14, 1991, with limitations, must wear lenses for distant vision, and posses glasses for near vision.

Mr. Templeton's records showing his total flight hours were not located. It was estimated from information provided by the FAA that he had a total of 1,300 flight hours.

Aircraft information

Documents found at the crash site indicated that the airplane was purchased in Canada, June, 1992, then flown to the United States. The airplane was flown to Florida were an annual inspection was completed on June 8, 1992, at a total time of 6643.45 hours. The next annual was due June 30, 1992. No records were found to indicate that N515WB had a current annual at the time of the accident.

The NTSB learned from the Airport Manager, at the Easton Airport, Maryland, that N515WB had been flown into the Easton Airport two weeks prior to the accident, and parked at the airport until it departed on the day of the accident. The Airport Manger revealed that he thought some maintenance might have been completed by a Mr. Les Brendal.

Mr. Brendal was contacted by phone, and he told the NTSB that he performed a hot end inspection, at the request of Mr. Stevenson.

Mr. Brendal indicated that he did not know the history of the airplane, but that he believed the airplane sat in Florida for two years, and that it was purchased two months prior to being flown to Maryland.

Documents found at the crash site indicated that Brent's International purchased N515WB from Mr. Stevenson, and that Mr. Stevenson agreed to fly the airplane to California, then to New Zealand. In the letters Mr. Stevenson, indicated that N515WB, had a total time of 6,688 hours. Based on the information obtained from this letter it was determined that at the time of the accident N515WB had 44.55 hours since the last annual inspection, on June 8, 1992.

Meteorological information

The NTSB Meteorological Factual Report, revealed that N515WB, was in Instrument Meteorological Conditions at the time of the altitude excursion that was noted by ATC. At FL 240 there was a probability of light to moderate turbulence, a temperature of minus 33 degrees C, with winds southwesterly at 50 to 60 knots. Ice crystals were predominant in the clouds.

Wreckage and impact information

The wreckage was examined at the accident site on December 3-5, 1993. The wreckage was scattered over a 3.5 mile area on a heading of 240 degrees. Among the first pieces of debris located on the wreckage path were small light weight pieces of internal vinyl (identified to have been part of the left forward baggage door lining), a section of wing skin, and tail skin. A 5 foot section of the left elevator was located on the wreckage path approximately 2.5 miles from the main wreckage. About 150 feet southwest from the left elevator section, a 12 foot long piece of the leading edge of the right horizontal stabilizer with the deicing boot was found. Approximately 200 feet southwest of the right horizontal stabilizer, was a 3 foot long piece of the right elevator with the trim tab still attached. All the debris found on the wreckage path was in a straight line. There was no evidence of any fire or soot accumulation to any structural pieces found on the wreckage path. The airplane came to rest inverted and was completely destroyed.

The forward pressure bulkhead was found crushed. The aft pressure bulk head was intact. No blowout holes or cracks were found on the aft bulkhead.

Control continuity was established to all flight controls by tracing the cables and control rods, with the exception of the elevator control rod. The elevator control rod was removed from the wreckage for further examination at the NTSB Materials Laboratory.

An examination of both engines was completed after the engines were removed from the accident site, and taken to a hanger at a near by airport. No discrepancies were observed.

The propellers were removed from the accident site, and shipped to Hartzell Propeller for examination.

The left forward baggage door had separated from the fuselage and was found forward of the left engine at the main wreckage site. The door was not crushed, but the door frame where the door had been attached to the fuselage was crushed. The door was removed from the crash site for further examination.

Medical and pathological information

An autopsy was performed on both pilots, Mr. Michael W. Stevenson and Mr. James E. Templeton, on December 3, 1993, at the Franklin County Medical Examiner's Office, Columbus, Ohio, by Dr. Patrick M. Fardal.

The toxicological tests on both men were conducted at the Armed Forces Institute of Pathology, Washington, DC, and revealed, "... no drugs or alcohol where found."

Test and research

A Trajectory Study, done by the NTSB, Vehicle Performance Division, revealed that the airplane breakup occurred at 7000 feet MSL, and the flight path angle was 45 degrees down. The breakup occurred approximately 0.75 statute miles southwest of the main wreckage sight.

The left forward baggage door was ex

Aircraft

Registration
N515WB
Reported as
Piper PA-31T
Category
Airplane
Serial number
7720023
Airframe hours
6,685
Engine
P&W PT6A-28, 620 horsepower, turbo prop
Damage
Destroyed
Flight
Ferry · Part 91
Registered owner
Brent'S International Inc.
Airworthiness certificate
Standard, Normal
Last inspection
Annual · June 8, 1992 · 45 hours before
Departed
ESN · Easton, MD
Destination
DSM · Des Moines, IA
Flight plan
IFR

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
Certificate
Airline transport
Airplane ratings
Single-engine sea, Multi-engine sea, Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Class 2, Valid Medical--w/ waivers/lim
Seat
Left
Toxicology
Performed
Flight hours
5,200 total · 3 in this make and model

Weather

Conditions
Visual (VMC) · Day
Wind
220° at 13 knots, gusting 18
Visibility
10 statute miles
Lowest ceiling
8,500 ft broken
Temperature
54 °F, dew point 46 °F
Altimeter
30.00 inHg
Observed at
CMH, 20 nm away

FAA reports on this event · 1

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