WPR22LA064

NTSB accident investigation · Beech A36 · Tooele, UT · November 24, 2021

Accident · No injuriesClass 3 · LimitedFinal report
Date
November 24, 2021, 12:40 local (19:40 UTC)
Place
Tooele, UT
Injuries
4 uninjured
Damage
Substantial damage
Phase of flight
Unknown
Aircraft
N4370WBeech A36
Defining event
Unknown: Unknown or undetermined
Weather
Visual (VMC) · Day
Status
Completed
Report
Approved by Office Director
Investigation class
Class 3
NTSB office
Western Pacific Region
Parties
Federal Aviation Adminsitration
FAA report
20211124019839A
Case key
104397

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

The total loss of engine power for reasons that could not be determined based on available evidence.

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 determinedBeech A36: 23 casesAll aircraft: 2,247 casesProbable cause

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 stated that he began a descent to pattern altitude at the destination airport. When he reduced the propeller speed to 2,200 rpm, a “slapping sort of knock began as well as a shimmy in the plane.” The pilot arrested the descent, observed that the oil temperature and oil pressure were normal, and looked outside the airplane to verify that the flight control surfaces had no issues. The pilot then noticed that the airspeed had decreased to 130 miles per hour and that the controls became “heavy and very mushy.” The pilot initiated a forced landing to a nearby road but abandoned that plan when he observed a vehicle traveling on the road. The pilot advanced the propeller and throttle levers full forward but received no response from the engine, and he noticed that the cylinder head temperature gauge had “dropped completely to the left.” The pilot maneuvered the airplane to avoid power lines and landed in an open desert area. During the landing, the airplane struck trees, impacted terrain, and came to rest at a nose-low attitude. Postaccident examination of the airframe and engine revealed no evidence of any pre-existing mechanical malfunction that would have precluded normal operation. Utilizing the reported fuel quantity at the time of departure and fuel burn rate for the reported power setting, it was determined that the pilot had an adequate amount of fuel for the intended flight. As a result, the reason for the total loss of engine power could not be determined.

Factual narrative

On November 24, 2021, about 1240 mountain standard time, a Beech A36, N4370W, was substantially damaged when it was involved in an accident near Tooele Valley Airport (TVY), Tooele, Utah. The pilot and three passengers were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot reported that the airplane departed from Safford, Arizona, with 80 gallons of fuel aboard. The pilot reported that, during cruise flight at 12,500 ft mean sea level (msl), he used a 65% power setting, consistent with the power setting in the Pilot Operating Handbook (POH) for that phase of flight. As the airplane neared Gunnison, Utah, which was about 85 miles south of TVY, he switched from the right fuel tank to the left fuel tank. Shortly afterward, the pilot initiated descents to 10,500 ft msl and then 8,500 ft msl while west of Provo, Utah. The pilot stated that he maintained a mixture setting of 50° rich of peak throughout the descent. As the airplane neared the Tooele Valley, he descended the airplane to 6,500 ft msl and maneuvered around a ridgeline. While descending to pattern altitude at the destination airport, the pilot reduced the propeller speed to 2,200 rpm, at which time a “slapping' sort of knock began, as well as a shimmy in the plane.” The pilot arrested the descent and observed that the oil temperature and oil pressure were normal. He then looked outside the airplane and verified that no control surface issues were occurring. Afterward, the pilot focused his attention on engine performance. The pilot stated that the airspeed had decreased to 130 miles per hour and that the controls became “heavy and very mushy.” The pilot initiated a forced landing to a nearby road, but he observed a vehicle that was traveling on the opposite direction of the road and decided not to land there. The pilot then advanced the propeller and throttle levers full forward but received no response from the engine. The pilot also noticed that the cylinder head temperature gauge had “dropped completely to the left of the gauge.” The pilot stated that he pitched the airplane upward to avoid power lines and landed in an open desert area. During the landing, the airplane struck multiple juniper trees before it impacted terrain and came to rest nose low, which resulted in substantial damage to the left wing. The airplane was equipped with two 40-gallon fuel tanks, of which, 74 gallons of fuel is usable. The POH indicated that at a 65% cruise power setting, fuel burn is between 10.0 and 13.3 gallons per hour. Postaccident examination of the airframe and engine revealed no evidence of any pre-existing mechanical malfunction that would have precluded normal operation of the engine.

Aircraft

Registration
N4370W
Reported as
Beech A36
Category
Airplane
Serial number
E-559
Built
1974
Airframe hours
5,334.73
Engine
Continental Motors IO-520-BA(10), 285 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Airworthiness certificate
Standard, Normal
Last inspection
Annual · January 11, 2021
Departed
SAD · Safford, AZ
Destination
Same as departure
Equipment
Stall warning system

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
47
Injuries
None
Certificate
Private
Airplane ratings
Single-engine land
Medical
BasicMed
Last flight review
December 2, 2016
Seat
Left
Restraint
3-point
Flight hours
207.8 total · 75.5 in this make and model · 145 as pilot in command · 12.9 in the last 90 days · 11.9 in the last 30 days

Weather

Conditions
Visual (VMC) · Day
Wind
360° at 9 knots
Visibility
10 statute miles
Temperature
37 °F, dew point 27 °F
Altimeter
30.39 inHg
Observed at
KTVY, 18 nm away
METAR
METAR KTVY 241935Z AUTO 36009KT 10SM SCT035 03/M03 A3039 RMK AO2=

Docket · 6

The files NTSB released with the investigation on July 6, 2023, on NTSB’s docket system: statements, records, photos and specialists’ reports. 6.7 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.