CEN21LA100

NTSB accident investigation · Walton Daniel J Sonex · Pecatonica, IL · December 24, 2020

Accident · Serious injuriesClass 3 · LimitedFinal report
Date
December 24, 2020, 14:40 local (20:40 UTC)
Place
Pecatonica, IL
Injuries
1 serious
Damage
Substantial damage
Phase of flight
Approach
Aircraft
N610DJWalton Daniel J Sonex
Defining event
Approach-VFR pattern base: Unknown or undetermined
Weather
Visual (VMC) · Day
Status
Completed · report December 24, 2020
Report
Approved by Office Director
Investigation class
Class 3
NTSB office
Central Region
Parties
FAA Flight Standards District Office
FAA report
20201224020249A
Case key
102461

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 total loss of engine power for reasons that could not be determined based on the available information, and the pilot’s exceedance of the airplane’s critical angle of attack following the loss of engine power, which resulted in an aerodynamic stall/spin and impact with terrain.

Findings · 3

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.

Engine (reciprocating)Aircraft › Aircraft power plant · Unknown/Not determinedWalton Daniel J SONEX: 1 caseAll aircraft: 497 casesProbable cause
Use of equip/info: aircraft controlPersonnel issues › Task performance · PilotWalton Daniel J SONEX: 1 caseAll aircraft: 9,295 casesProbable cause
Performance/control parameters: angle of attackAircraft › Aircraft oper/perf/capability · Capability exceededWalton Daniel J SONEX: 1 caseAll aircraft: 990 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 did not provide a statement regarding the accident. Information from the Federal Aviation Administration indicated that, while on the downwind leg of the airport traffic pattern for landing, the pilot reduced engine power and the engine lost total power. The airplane continued in a left turn toward the runway while the pilot attempted to restart the engine. The airplane entered a stall/spin and impacted terrain, resulting in substantial damage. Postaccident examination of the airplane and engine did not reveal any anomalies that would have precluded normal operation, and the reason for the loss of engine power could not be determined. Based on the available information, the circumstances of the accident are consistent with the pilot’s exceedance of the airplane’s critical angle of attack following a loss of engine power, which resulted in an aerodynamic stall/spin and impact with terrain.

Factual narrative

On December 24, 2020, about 1440 central standard time, an experimental, amateur-built Sonex, N610DJ, was involved in an accident near Pecatonica, Illinois. The pilot sustained serious injuries. The airplane was operated as a Title 14 Code of Federal Regulations (CFR) Part 91 personal flight. The pilot did not provide a statement regarding the accident. Information from the Federal Aviation Administration indicated that, when the pilot reduced engine power to 2,000 rpm while on the downwind leg of the traffic pattern for landing, the engine lost total power. The airplane remained in a left turn while the pilot attempted to restart the engine, and the pilot stated that he lost control effectiveness during the turn. The airplane entered a stall/spin, then impacted terrain. The airplane sustained substantial damage to the fuselage and wings. Postaccident examination of the airplane revealed that the fuel tank was at least 1/3 full of fuel and was leaking from impact damage. The fuel lines to the engine were attached and secure. The engine could be rotated, and engine drive train and valve train continuity were confirmed. The carburetor bowl contained 100 low lead aviation fuel, and the carburetor float moved freely. The spark plugs electrodes exhibited normal coloration/features.

Aircraft

Registration
N610DJ
Reported as
Walton Daniel J Sonex
Category
Airplane, amateur-built
Serial number
0959
Built
2010
Engine
Aerovee 2180, 80 horsepower
Damage
Substantial damage
Flight
Personal · Part 91
Operator
Pilot
Registered owner
Schroepfer Andrew M
Airworthiness certificate
Special, Experimental (Special)
Departed
DNV · Danville, IL
Destination
Same as departure
Airport
8IL5 · Pecatonica, runway 9, 1,800 × 70 ft, grass/turf
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
30
Injuries
Serious
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 3, Without waivers/limitations
Flight hours
120 total · 70 in this make and model · 40 in the last 90 days

Weather

Conditions
Visual (VMC) · Day
Wind
290° at 14 knots, gusting 21
Visibility
8 statute miles
Lowest ceiling
3,600 ft broken
Temperature
16 °F, dew point 1 °F
Altimeter
29.84 inHg
Observed at
KRFD, 13 nm away
METAR
KRFD 241754Z 29014G21KT 8SM -SN SCT025 BKN036 OVC042 M09/M17 A2984 RMK AO2 SLP117 P0000 60000 T10891172 11078 21111 51007

Docket · 5

The files NTSB released with the investigation on June 21, 2022, on NTSB’s docket system: statements, records, photos and specialists’ reports. 578 KB 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.