SEA94LA061

NTSB accident investigation · Piper PA-24 · Cheyenne, WY · February 10, 1994

Accident · No injuriesLimited investigationFinal report
Date
February 10, 1994, 16:05 local (23:05 UTC)
Place
Cheyenne, WY
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N5639PPiper PA-24
Weather
Visual (VMC) · Day
Status
Completed · report January 26, 1995
Report
Approved by Office Director
Case key
41876

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 improper use of the carburetor heat. A factor to the accident was carburetor icing conditions.

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 engine power(total) - nonmechanicalDescent - normal
Weather condition - carburetor icing conditionsFactor
Fuel system,carburetor - ice
Carburetor heat - improper use ofPilot in commandCause
Forced landingDescent - emergency
Gear not extendedLanding

Analysis

During cruise flight, the pilot diverted course to avoid snow showers. The pilot was unable to stay clear of the showers at his present altitude and opted to descend. During the descent, the pilot applied carb heat after he noticed a drop in the EGT. The engine lost power shortly thereafter. The pilot was unable to regain full power and a forced landing was made with the landing gear retracted. The carburetor icing probability chart indicates icing at glide and cruise power.

Factual narrative

On February 10, 1994, at 1605 mountain standard time, a Piper PA- 24, N5639P, experienced a loss of engine power while descending. The pilot initiated a forced landing to an open area and landed the airplane gear up, 24 miles southwest of Cheyenne, Wyoming. Visual meteorological conditions prevailed at the time and a visual flight rules flight plan was filed. The airplane was substantially damaged and the certificated airline transport pilot and his passenger were not injured. The flight had departed from Cody, Wyoming, on February 10, 1994, at 1355 and was en route to Colorado Springs, Colorado, on the personal flight.

In a written statement, the pilot reported that while in cruise flight to Colorado Springs, the airplane was approximately 25 miles south of Laramie, Wyoming, when the flight encountered a line of snow showers. The pilot diverted to the east in an attempt to get around the showers, however, the flight was unable. The pilot opted to descend in altitude and noticed that the exhaust gas temperature had dropped. The pilot applied carburetor heat and the engine lost power. The pilot returned the carburetor heat control to the mid range position and the engine recovered momentarily. The pilot made adjustments to the mixture and carburetor heat, however, the engine would only surge until it finally lost power. The pilot then selected a location for a forced landing with the landing gear retracted.

The accident site was located approximately 24 miles southwest of Cheyenne, Wyoming. The Cheyenne weather facility reported at 1551, that the temperature was 33 degrees and the dew point was 21 degrees. The Carburetor Icing Probability Chart indicates at these temperatures, carbureting icing was possible at glide and cruise power.

Aircraft

Registration
N5639P
Reported as
Piper PA-24
Category
Airplane
Serial number
24-709
Airframe hours
3,289
Engine
Lycoming O-360-AIA, 180 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Operator
Jackson, Myron K.
Registered owner
Jackson, Myron K.
Airworthiness certificate
Standard, Normal
Last inspection
Annual · June 23, 1993 · 89 hours before
Departed
COD · Cody, WY
Destination
COS · Colorado Spring, CO
Flight plan
VFR

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
62
Certificates
Commercial, Airline transport
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Class 2, Valid Medical--w/ waivers/lim
Seat
Left
Flight hours
18,604 total · 82 in this make and model · 16,100 as pilot in command · 10 in the last 90 days · 4 in the last 30 days · 2 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
180° at 12 knots
Visibility
30 statute miles
Lowest ceiling
4,500 ft overcast
Temperature
34 °F, dew point 21 °F
Altimeter
29.00 inHg
Observed at
WOF, 24 nm away