WPR23LA343

NTSB accident investigation · Boeing A75N1(PT17) · Monticello, UT · September 13, 2023

Accident · Minor injuriesClass 3 · LimitedFinal report
Date
September 13, 2023, 11:00 local (17:00 UTC)
Place
Monticello, UT · Open field
Injuries
1 minor
Damage
Substantial damage
Phase of flight
Initial climb
Aircraft
N10KPBoeing A75N1(PT17)
Defining event
Initial climb: Unknown or undetermined
Weather
Visual (VMC) · Day
Status
Completed
Report
Approved by Office Director
Investigation class
Class 3
NTSB office
Western Pacific Region
Parties
FAA
FAA report
20230913015599A
Case key
193063

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

A partial loss of engine power for reasons that could not be determined.

Findings · 1

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Not determinedNot determined › Not determined · Unknown/Not determinedBoeing A75N1(PT17): 8 casesAll aircraft: 2,247 cases

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

The pilot departed the airport, conducted a low pass over the runway, and was climbing the airplane to pattern altitude when the engine began to lose power. The pilot stated that the engine did not lose complete power; however, the rpm and airspeed continued to decline and he chose to make a forced landing. The airplane landed in heavily vegetated terrain and during the landing roll the left main landing gear collapsed, resulting in substantial damage to the lower left wing. A postaccident examination of the airframe and engine revealed no evidence of any preaccident mechanical malfunctions or failures that would have precluded normal operation. Although remnants of a high-temperature cloth were found between the air filter and particle screen, no debris was found in the filter or induction screen and the air intake did not appear to be impeded. Based on the available information, the reason for the loss of engine power could not be determined.

Factual narrative

On September 13, 2023, at 1100 mountain daylight time, a Boeing Stearman A75N1 (PT-17), N10KP, was substantially damaged when it was involved in an accident near Monticello, Utah. The pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot reported that, after performing the preflight checklist and engine run-up, he departed from runway 16 and remained in the airport traffic pattern. He conducted a low pass over the runway, made a left crosswind turn, and began a climb. About 500 ft above the ground, the engine began to lose power. The engine did not exhibit a complete loss of power, but engine rpm and airspeed continued to decline. The pilot chose to make a forced landing to flat, sage brush-covered terrain. The left main landing gear collapsed during the landing roll, resulting in substantial damage to the lower left wing when it struck the surface. Examination of the airframe and engine revealed no evidence of any preaccident mechanical malfunctions or failures that would have precluded normal operation. Throttle and mixture control continuity was established from the rear cockpit controls to the engine. The fuel system was intact with no fuel leaks observed. The front spark plugs were removed, and the propeller was rotated by hand. Rotational continuity was established throughout the engine and valvetrain, and thumb compression was obtained for all 9 cylinders. The starter was engaged, and spark was obtained at all ignition leads. Removal of the induction system revealed remnants of a high-temperature cloth between the air filter and particle screen. No additional cloth debris was observed in the filter or induction screen. The carburetor remained secure at its mount and when the throttle was actuated by hand fuel was expelled from the accelerator pump port. The carburetor fuel screen was free of debris. The carburetor was removed and disassembled with no discrepancies noted. Fuel was obtained from the airframe fuel filter, carburetor, and fuel tank; all fuel samples were free of debris and blue in color. A review of the weather conditions reported by Blanding Municipal Airport (BDG), Blanding, Utah, about 21 nautical miles southwest of the accident site, indicated a temperature of 64.4°F, and a dew point of 50°F around the time of the accident.

Aircraft

Registration
N10KP
Reported as
Boeing A75N1(PT17)
Category
Airplane
Serial number
755247
Built
1942
Airframe hours
5,833.7
Engine
Lycoming R680-17, 225 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Airworthiness certificate
Standard, Normal
Last inspection
Annual · October 1, 2022 · 7 hours before
Departed
U64 · Monticello, UT
Destination
Same as departure
Airport
U64 · Monticello
Equipment
Unknown

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
72
Injuries
Minor
Certificate
Private
Airplane ratings
Single-engine land
Medical
BasicMed, Unknown
Last flight review
September 22, 2022
Seat
Rear
Flight hours
0 total · 0 in this make and model

Weather

Conditions
Visual (VMC) · Day
Wind
80° at 6 knots
Visibility
10 statute miles
Lowest ceiling
3,400 ft overcast
Temperature
64 °F, dew point 50 °F
Altimeter
30.20 inHg
Observed at
KBDG, 21 nm away
METAR
KBDG 131715Z AUTO 08006KT 10SM OVC034 18/10 A3020 RMK AO2 T01840098

Docket · 6

The files NTSB released with the investigation on March 5, 2025, on NTSB’s docket system: statements, records, photos and specialists’ reports. 4.4 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.