ERA21LA298

NTSB accident investigation · Carpenter Stol CH750 · Rockwell, NC · July 21, 2021

Accident · No injuriesClass 3 · LimitedFinal report
Date
July 21, 2021, 16:44 local (20:44 UTC)
Place
Rockwell, NC
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N750RSCarpenter Stol CH750
Defining event
Enroute: Fuel related
Weather
Visual (VMC) · Day
Status
Completed
Report
Approved by Office Director
Investigation class
Class 3
NTSB office
Eastern Region Aviation
Parties
FAA FSDO
FAA report
20210721011319A
Case key
103546

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 due to carburetor ice. Also causal was the pilot’s failure to apply carburetor heat at any time during the flight.

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.

Temp/humidity/pressure: conducive to carburetor icingEnvironmental issues › Conditions/weather/phenomena · Effect on equipmentRichard S Carpenter STOL CH 750: 1 caseAll aircraft: 435 casesProbable cause
Action: lack of actionPersonnel issues › Action/decision · PilotRichard S Carpenter STOL CH 750: 1 caseAll aircraft: 792 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

About 30 minutes into the flight the engine “burped” then progressively lost power. The pilot switched fuel tanks but described no other remedial actions before the engine lost all power. The pilot selected an open field adjacent to a roadway for a forced landing where the airplane nosed over and came to rest inverted, sustaining substantial damage. Atmospheric conditions at the time of the accident were conducive to carburetor icing, and the airplane was fueled with automotive gasoline, which increased its likelihood. After the accident, a fuel can of aviation gasoline was plumbed into the fuel supply line at the left-wing root, and an engine start was attempted. The engine started immediately, accelerated smoothly, and ran continuously without interruption through several power changes. Both a magneto and carburetor heat check were performed satisfactorily. The pilot reported that he did not apply carburetor heat during the accident flight.

Factual narrative

On July 21, 2021, at 1644 eastern daylight time, an experimental, amateur-built STOL CH 750, N750RS was substantially damaged when it was involved in an accident near Rockwell, North Carolina. The private pilot was not injured. The personal flight was conducted under the provisions of Title 14 Code of Federal Regulations Part 91. About 30 minutes into the flight the engine “burped” and then progressively lost power as it ran more roughly, and the airplane descended. The pilot switched fuel tanks but described no other remedial actions before the engine lost all power. The pilot selected an open field adjacent to roadway for the forced landing. According to the pilot the airplane was in the landing flare, about 5 ft above the ground, when the “airplane stalled and dropped out from under me.” The airplane eventually nosed over and came to rest inverted. Examination of photographs revealed damage to the wings and fuselage and substantial damage to the rudder/vertical stabilizer. One of three propeller blades was fractured at its root. The responding police officer released the airplane to the owner, who removed the wings, drained the fuel from the wings, and hired a local wrecking service to recover the airplane from the scene. An aircraft recovery service then recovered the airplane to their facility. Once there, recovery personnel drained about 1/2 pint of automotive gasoline from the gascolator. They replaced the propeller, cleared the intake of sod from the accident site, plumbed a fuel can of aviation gasoline into the fuel supply line at the left-wing root, and attempted an engine start. The engine started immediately, accelerated smoothly, and ran continuously without interruption through several power changes. Both a magneto and carburetor heat check were performed satisfactorily. Atmospheric conditions at the time of the accident were conducive to “serious icing at glide power.” Federal Aviation Administration (FAA) Technical Center testing indicated that carburetor icing will occur in less time and at higher ambient temperatures with automotive gasoline than with aviation gasoline. The pilot reported to the FAA inspector that he did not apply carburetor heat during the accident flight.

Aircraft

Registration
N750RS
Reported as
Carpenter Stol CH750
Category
Airplane, amateur-built
Serial number
75-8221
Built
2011
Engine
Continental O-200, 100 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Airworthiness certificate
Special, Experimental (Special)
Last inspection
Condition · July 20, 2021 · 0.7 hours before
Departed
PVT · Concord, NC
Airport
NA
Equipment
ADS-B

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
71
Injuries
None
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 3, Without waivers/limitations
Last flight review
August 25, 2020
Seat
Left
Restraint
4-point
Flight hours
706 total · 7.1 in this make and model · 706 as pilot in command

Weather

Conditions
Visual (VMC) · Day
Wind
Calm
Visibility
10 statute miles
Lowest ceiling
None
Temperature
86 °F, dew point 64 °F
Altimeter
30.00 inHg
Observed at
KRUQ, 7 nm away
METAR
KRUQ 211955Z AUTO 00000KT 10SM CLR 30/18 A3000 RMK AO2 T03000184

Docket · 6

The files NTSB released with the investigation on July 6, 2023, on NTSB’s docket system: statements, records, photos and specialists’ reports. 18.3 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.