DEN99LA061

NTSB accident investigation · Mooney M20K · Medicine Bow, WY · March 28, 1999

Accident · No injuriesLimited investigationFinal report
Date
March 28, 1999, 15:15 local (22:15 UTC)
Place
Medicine Bow, WY
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N12HWMooney M20K
Weather
Visual (VMC) · Day
Status
Completed · report April 25, 2001
Report
Approved by Office Director
FAA report
19990328040339A
Case key
45988

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

A fluctuating turbine inlet temperature and resulting loss of engine power for undetermined reasons. Factors were the rough, unsuitable terrain on which to make a forced landing.

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(partial) - mech failure/malfCruise
Engine instruments,tit gage - fluctuatingCause
Reason for occurrence undeterminedCause
Forced landingEmergency descent/landing
Hard landingEmergency landing
Terrain condition - open field
Terrain condition - rough/unevenFactor
Terrain condition - none suitableFactor

Analysis

Upon reaching 23,000 feet msl, the pilot leaned the engine's turbine inlet temperature (TIT). About 5 to 10 minutes later, the TIT started rising. He requested and received a clearance to descend to 17,000 feet. The TIT continued to climb, and he requested another descent to 12,000 and reduced power. At that time, the 'engine started to run very rough, popping and spitting and not developing any power.' He requested assistance for vectors to the closest airport. After locating the airport, he observed a tractor positioned in the middle of the runway, and selected a field 1/4 mile east of the airport on which to land. The aircraft landed hard, damaging the right wing and landing gear. Several postaccident examinations of the engine were performed. Fuel was observed in the engine and the fuel tanks and was present in each of the fuel injector nozzles. The fuel boost pump was turned off and the engine surged. The engine driven fuel pump was bench and flow tested, and no discrepancies were observed. A replacement turbocharger was installed on the engine and test run, and the engine continued to run rough and surge. Nothing was found during the investigation to determine what caused the loss of engine power.

Factual narrative

On March 28, 1999, at 1515 mountain standard time, a Mooney M20K, N12HW, was substantially damaged during a forced landing following a loss of engine power while in cruise flight near Medicine Bow, Wyoming. The private pilot, the sole occupant aboard, was not injured. The aircraft was being operated by Blazie Marketing Service of Forest Hill, Maryland, under Title 14 CFR Part 91. The cross-country flight originated from the Salt Lake City International Airport, Salt Lake City, Utah, approximately 1315. A VFR flight plan had been filed; however, an IFR clearance had been activated 50 miles northwest of Medicine Bow for the flight to Omaha, Nebraska. Visual meteorological conditions prevailed at the accident site.

According to the pilot, approximately an hour and a half after departing Salt Lake City, he began encountering instrument meteorological conditions. He requested an IFR clearance to climb to 23,000 feet mean sea level (msl). He received a clearance, and upon reaching his requested altitude, he leaned the engine's turbine inlet temperature (TIT) to 1600. The pilot stated that everything appeared normal for the first 5 to 10 minutes, then the TIT started rising. He applied full rich mixture, and the TIT came down.

He requested and received a clearance to descend to 17,000 feet. The TIT continued to climb, and he requested another descent to 12,000 and continued to reduce power. At that time, the "engine started to run very rough, popping and spitting and not developing any power." He requested assistance from Denver Center (ARTCC) for vectors to the closest airport. At approximately 2,000 to 3,000 feet above the ground, he broke out of the clouds and located the Medicine Bow Airport. He observed a tractor positioned in the middle of the runway, and he selected a field 1/4 mile east of the airport on which to land. After a hard landing, the aircraft sustained damage to the right wing and the right landing gear.

Two postaccident examinations of the engine were performed by FAA maintenance inspectors. Fuel was observed in the fuel tanks, engine, and the fuel injector nozzles. No fuel leaks were detected, and the oil quantity level was normal. The fuel flow divider appeared to be dry. No engine discrepancies were noted.

Another engine examination was performed at Western Skyways in Montrose, Colorado. With the fuel boost pump on, the engine ran normally at ranges varying between 1,300 to 1,800 rmp. With the boost pump off, the engine began to surge at those rpm settings. The engine driven fuel pump was bench and flow tested and no discrepancies were found. The entire fuel system, including the fuel injectors and servo controller, was replaced with new parts, and the engine continued to surge. A replacement turbocharger was installed on the engine and test run. The engine continued to run rough and surge with the replacement turbocharger. Nothing was found during the investigation to determine what caused the loss of engine power.

Aircraft

Registration
N12HW
Reported as
Mooney M20K
Category
Airplane
Serial number
25-0557
Airframe hours
2,486
Engine
Continental TSIO-520-NB83, 305 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Registered owner
Blazie Marketing Service
Airworthiness certificate
Standard, Normal
Last inspection
Annual · July 1, 1998
Departed
SLC · Salt Lake City, UT
Destination
OMA · Omaha, NE
Flight plan
VFR
Airport
80V · Medicine Bow 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
30
Certificate
Private
Airplane ratings
Single-engine land
Instrument ratings
Airplane
Medical
Class 2, Valid Medical--no waivers/lim.
Seat
Left
Flight hours
2,500 total · 2,000 in this make and model · 2,500 as pilot in command · 57 in the last 90 days · 38 in the last 30 days · 2 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Visibility
10 statute miles
Lowest ceiling
3,000 ft overcast
Temperature
30 °F

FAA reports on this event · 1

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