DEN00FA021

NTSB accident investigation · Piper PA-18-125 · Afton, WY · November 28, 1999

Accident · FatalField investigationFinal report
Date
November 28, 1999, 10:05 local (17:05 UTC)
Place
Afton, WY
Injuries
2 fatal
Damage
Destroyed
Phase of flight
Initial climb
Aircraft
N1132APiper PA-18-125
Weather
Instrument (IMC) · Not reported
Status
Completed · report November 2, 2000
Report
Approved by Office Director
FAA report
19991128040319A
Case key
47811

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 NTSB’s determination of the probable cause, and any contributing factors.

Failure of the pilot to remove frost from the wings prior to takeoff, causing an inadvertent stall/spin on initial climbout. Factors included exceeding the aircraft's certificated gross weight, and fog conditions.

Analysis

The airplane was tied down on the ramp overnight. The pilot did not obtain a weather briefing or file a flight plan, and no airplane services were rendered. Witnesses said there was 'stand up' frost, 1/4 to 1/2 inch thick, on parked airplanes nearby. The temperature was near freezing, the wind was calm, and a heavy fog enveloped the airport when the airplane took off. It impacted terrain 400 yards west of the runway and burned. It was computed the airplane was 115 pounds overweight at takeoff.

Factual narrative

The factual narrative1,234 words

History of flight

On November 28, 1999, approximately 1005 mountain standard time, a Piper PA-18-125, N1132A, registered to and operated by the pilot, was destroyed when it impacted terrain adjacent to the Afton Municipal Airport, Afton, Wyoming. The commercial pilot and his passenger were fatally injured. Instrument meteorological conditions prevailed, and no flight plan had been filed for the personal cross-country flight being conducted under Title 14 CFR Part 91. The flight was originating at the time of the accident.

The pilot and his passenger were en route home to Nampa, Idaho, after spending the Thanksgiving holidays with the passenger's parents in Oshkosh, Nebraska. According to one local pilot who was doing touch-and-go landings at the airport, it was dark when N1132A landed. The pilot taxied the airplane to a service station next to the airport, located at 1850 S. Washington Street, and refueled. According to the Trailside Store clerk, the pilot paid $24.73 for 18.199 gallons of regular 85 octane unleaded automotive gasoline. The time stamped on the cash receipt was 2037.

The pilot tied down his airplane on the ramp and secured the use of the airport's courtesy car. He and his passenger then checked into the Mountain Inn Motel. The bill was paid using the passenger's credit card.

The next morning approximately 0900, two Aviat test pilots were preflighting an airplane for departure and noticed the pilot and his passenger trying to jump start their airplane's engine. They said that when they departed Afton on a test flight, there was a fog bank to the west of the airport but the runway was clear, and the pilot and his passenger were still trying to start their engine.

There is no record that the pilot obtained a weather briefing or filed a flight plan. At 1038 and again at 1045, a witnesses saw a fire in a field next to the airport. Upon closer examination, one witness discovered it was an airplane. The fire department was notified at 1048.

Personnel information

The pilot, age 29, was born on May 5, 1970. He held a commercial pilot certificate with rotorcraft-helicopter and instrument-helicopter ratings, and private pilot privileges with an airplane single-engine land rating. His second class airman medical certificate, dated August 20, 1999, contained no restrictions or limitations.

The pilot's logbook was never located. He was, however, a chief warrant officer (CWO-2) with "B" Company, 1st Battalion, 183rd Aviation Regiment, Idaho Army National Guard, headquartered at the Boise Air Terminal. According to ANG flight records (DA Form 759-E, attached, see EXHIBITS), he had accrued 659.5 total hours in military helicopters as of May 31, 1999. He was currently flying the AH64 Apache attack helicopter. According to FAA records, when he applied for his most recent medical certification (August 20, 1999), he estimated his total civilian flight time at 1,200 hours, of which 200 hours were acquired within the preceding 6 months. According to the pilot's aircraft insurance application, dated May 1999, he listed his total time as 1,930 hours, of which 240 hours were in the Piper PA-18-125, and 560 hours were in conventional (tail wheel equipped) airplanes. He indicated his last biennial flight review had been accomplished on April 29, 1999.

Aircraft information

N1132A (s/n 18-726) was manufactured by the Piper Aircraft Corporation in 1951. It was equipped with a Lycoming O-290-D reciprocating engine (s/n 2245-21), rated at 125 horsepower, and a Sensenich 2-blade, all-metal, fixed pitched propeller (m/n 74DM6-0-52, s/n A40725). The maintenance records reflect the following history:

On April 30, 1997, the engine received a major overhaul. Total time-in-service on the airframe and engine was 1,527.0 hours, and the tachometer was reset to 000:00. At the same time, the airplane was reassembled and rigged after being completely recovered, and new lift struts (satisfying A.D. 93-10-06) were installed. The airplane was re-weighed and the following was recorded:

Empty weight x C.G. = Moment

1,063 pounds x 15.1 = 16.064 inch/pounds

Useful load = 437 pounds

On March 4, 1999, the propeller was stripped, re-pitched from 56 inches to 52 inches, alodined and painted. The last annual inspection was dated June 1, 1999, at a tachometer time of 226.1 hours and a total time-in-service of 1,753.1 hours.

The maintenance records indicated the airplane did have a supplemental type certificate (STC) for the use of use automotive gasoline.

Meteorological information

Afton Municipal Airport does not have a weather observer, nor is it equipped with any sort of automated weather observation and recording apparatus. The nearest automated weather observation system (AWOS-3) is at Jackson Hole Airport, Jackson, Wyoming, located 54 miles north of Afton (attached, see EXHIBITS).

Witnesses said thick fog enveloped the airport before and after the accident, and airplanes parked outside on the ramp were covered with heavy frost. N1132A had been tied down on the ramp overnight. Ground frost was reported by police and CFR (crash/fire/rescue) personnel when they arrived at the accident site. Visibility varied from 50 feet to 1/4-mile. The temperature was near freezing, and the wind was calm. One witness said that when he discovered the burning airplane, the visibility was between 1/4 and 1/2-mile with "moisture in the fog." He also stated that he had put an airplane that had remained outside overnight into a heated hanger to melt off the frost, and he estimated the "stand up frost" to be between 1/4 and 1/2 thick on the wings.

Aerodrome information

Afton Municipal Airport (AFO), elevation 6,201 feet msl, is located 1 mile south of the town of Afton. It has one runway, 16-34, 5,220 ft. x 75 ft., asphalt. It is the home of Aviat Aircraft, Inc., manufacturers of the Husky and Pitts line of airplanes.

Wreckage and impact information

Based on wind conditions, witness reports, and wreckage examination, the airplane took off on runway 34 and shortly thereafter impacted a flat field approximately 400 yards west of the runway. A faint ground scar, 28 feet, 6 inches in length and aligned on a magnetic heading of 345 degrees, terminated at a crater. The crater was 3 feet long and 2 feet wide. The airplane was 17 feet beyond the crater. Magnetic alignments of the forward and aft cabin sections were 240 and 220 degrees, respectively. The flaps were retracted, and the elevator jackscrew indicated an approximately neutral setting. The passenger's watch had stopped at 1005.

All major structural components remained attached. Flight control continuity was established. The engine remained attached to the firewall mounts, and the propeller remained attached to the crankshaft. The crankshaft rotated freely by hand. The propeller spinner was crushed aft in torsion. Both propeller blades were bent aft somewhat, there was some gouging along the leading edges, and there were 90 degree chordwise scratches on the cambered surfaces.

Medical and pathological information

An autopsy (A99-11) was performed on the pilot by Dr. Philip L. Dutt. Additionally, a toxicological screen was performed by FAA's Civil Aeromedical Institute (CAMI). According to CAMI's report (#9900296001), no carbon monoxide, hydrogen cyanide, ethanol (alcohol), or drugs were detected in blood samples.

Tests and research

A weight and balance was computed for N1132A at the time of the takeoff and accident. Whereas the airplane was within c.g. (center of gravity) limits, it was computed to be 115 pounds over its certificated maximum gross weight (attached, see EXHIBITS).

Additional information

In addition to the Federal Aviation Administration, Textron-Lycoming was designated a party to this investigation. The New P

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 flightTakeoff - initial climb
Ice/frost removal from aircraft - not performedPilot in commandCause
Aircraft weight and balance - exceededPilot in commandFactor
Flight into adverse weather - intentionalPilot in command
Weather condition - fogFactor
Stall/spin - inadvertentPilot in commandCause
In flight collision with terrain/waterDescent - uncontrolled
Terrain condition - open field
Terrain condition - frozen

Aircraft

Registration
N1132A
Reported as
Piper PA-18-125
Category
Airplane
Serial number
18-726
Airframe hours
1,826
Engine
Lycoming O-290-D, 125 horsepower, reciprocating
Damage
Destroyed
Fire
Unknown
Flight
Personal · Part 91
Registered owner
Troy A. Baum
Airworthiness certificate
Standard, Normal
Last inspection
Annual · June 1, 1999 · 73 hours before
Departed
AFO
Destination
S67 · Nampa, ID
Airport
AFO · Afton Municipal, runway 34, 5,220 × 75 ft, asphalt

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
29
Certificates
Private, Commercial
Airplane ratings
Single-engine land
Instrument ratings
Helicopter
Medical
Class 2, Valid Medical--no waivers/lim.
Seat
Front
Toxicology
Performed
Flight hours
1,200 total · 100 in the last 90 days

Weather

Conditions
Instrument (IMC) · Not reported
Visibility
0.25 statute miles
Lowest ceiling
100 ft
Temperature
34 °F

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 N1132A · 1

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