WPR22LA133

NTSB accident investigation · Adams Dennis Allen Varieze · Mojave, CA · March 26, 2022

Accident · Serious injuriesClass 3 · LimitedFinal report
Date
March 26, 2022, 12:00 local (19:00 UTC)
Place
Mojave, CA · Open Field
Injuries
1 serious, 1 minor
Damage
Substantial damage
Phase of flight
Initial climb
Aircraft
N88KLAdams Dennis Allen Varieze
Defining event
Initial climb: Loss of engine power (total)
Weather
Visual (VMC) · Day
Status
Completed
Report
Approved by Office Director
Investigation class
Class 3
NTSB office
Western Pacific Region
Parties
FAA
FAA report
20220326004329A
Case key
104845

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

The failure of the carburetor intake Sceet tubing, which resulted in a total loss of engine power.

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.

Power plant: air intakeAircraft › Aircraft power plant · FailureAdams Dennis Allen VARIEZE: 1 caseAll aircraft: 50 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 reported that, after takeoff and about 500 ft above ground level, the engine lost total power and he chose to land on the open desert terrain. During the landing roll, the airplane collided with vegetation and the landing gear separated, resulting in substantial damage to the fuselage undercarriage. Examination of the airplane revealed that the air intake duct between the air filter box and the carburetor was damaged during the accident sequence and partially separated from the airplane. The ducting was Sceet tubing that comprised wire coil encased between an inner and outer silicone-impregnated layer. The Sceet tubing was disassembled and exhibited debonding of the inner and outer layers. Oil and debris that was not consistent with the accident sequence were present in the debonded area. It is likely that the loss of engine power was due to the separation of the Sceet tubing inner layer, which then restricted airflow to the carburetor.

Factual narrative

On March 26, 2022, about 1200 Pacific daylight time, an experimental, amateur-built VariEze, N88KL, was substantially damaged when it was involved in an accident near Mojave, California. The pilot sustained minor injuries and the pilot-rated passenger sustained serious injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot reported that he departed from runway 26, and turned left to the south. About 500 ft above ground level (agl), the engine lost total power. As the pilot continued the left turn back toward the airport, he realized that the airplane would not reach the runway and he chose to land in open desert terrain. During the landing roll, the airplane collided with vegetation and the landing gear separated, resulting in substantial damage to the fuselage undercarriage. Postaccident examination of the airplane revealed that the air intake duct between the air filter box and the carburetor was damaged during the accident sequence and partially separated from the airplane. The ducting was about 2 inches in diameter and consistent with Sceet tubing with both an inner and outer silicone-impregnated cloth with a wire coil between the layers. The Sceet tubing was disassembled and exhibited debonding of the inner and outer layer. Oil and debris that was not consistent with the accident sequence was present between the debonded area. The separation of the inner layer was consistent with unsupported areas during a negative pressure flow during engine operation.

Aircraft

Registration
N88KL
Reported as
Adams Dennis Allen Varieze
Category
Airplane, amateur-built
Serial number
1644
Built
1983
Airframe hours
1,192
Engine
Continental Motors O-200-A, 100 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Airworthiness certificate
Special, Experimental (Special)
Last inspection
Condition · March 20, 2022
Airport
MHV · Mojave Air and Space Port
Equipment
Electronic flight bag or handheld device

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 · 2

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
26
Injuries
Minor
Certificates
Commercial, Flight instructor
Airplane ratings
Single-engine sea, Multi-engine land, Single-engine land
Instrument ratings
Airplane
Medical
Class 1, Without waivers/limitations
Last flight review
August 16, 2020
Seat
Front
Restraint
4-point
Flight hours
1,478 total · 120 in this make and model · 1,334 as pilot in command · 74 in the last 90 days · 19 in the last 30 days · 2 in the last 24 hours
Role
Pilot-rated passenger
Age
38
Injuries
Serious
Certificate
Commercial
Airplane ratings
Multi-engine land, Single-engine land
Instrument ratings
Airplane
Medical
Class 2, Without waivers/limitations
Seat
Center
Restraint
4-point

Weather

Conditions
Visual (VMC) · Day
Wind
200° at 16 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
79 °F, dew point 7 °F
Altimeter
29.95 inHg
Observed at
KMHV, 2 nm away
METAR
KMHV 261900Z AUTO 20016KT 10SM CLR 26/M14 A2995 RMK A01

Docket · 6

The files NTSB released with the investigation on August 15, 2023, on NTSB’s docket system: statements, records, photos and specialists’ reports. 3.5 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.