WPR16LA174

NTSB accident investigation · Schneider K/Cook C SC Skybolt · Corvallis, OR · August 24, 2016

Accident · No injuriesClass 3 · LimitedFinal report
Date
August 24, 2016, 15:00 local (22:00 UTC)
Place
Corvallis, OR
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Taxi
Aircraft
N300SBSchneider K/Cook C SC Skybolt
Defining event
Taxi: Landing gear collapse
Weather
Visual (VMC) · Day
Status
Completed
Report
Approved by Office Director
Investigation class
Class 3
NTSB office
Western Pacific Region
Parties
FAA Portland FSDO
Case key
93973

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 collapse of the left main landing gear truss due to a weld joint failure, which resulted in substantial damage to the fuselage frame structure.

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.

Landing gear system: main landing gearAircraft › Aircraft systems · Fatigue/wear/corrosionSchneider K/Cook C SC SKYBOLT: 1 caseAll aircraft: 241 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 father of the passenger reported that his son, who was the passenger and owner, had just purchased the airplane, that a prepurchase inspection was conducted, and that “everything looked good.” The pilot was conducting a personal, local flight in the airplane, which included normal maneuvers and several touch-and-go landings with no issues. However, after the last landing and while taxiing the airplane back to the ramp, the left main landing gear (MLG) collapsed. Examination of the left MLG’s truss structure, which is welded to the fuselage, revealed substantial damage to the fuselage frame structure. Examination also revealed that a weld joint where the truss mounts to the fuselage was cracked and broken. Rust was noted around the weld area, and it appeared that a previous crack had been repaired. The father reported that the area of the failure was hidden behind the bungee and was not visible during the prepurchase inspection. Given the evidence, it is likely that the left main landing gear collapsed due to the weld joint failure.

Factual narrative

On August 24, 2016, about 1500 Pacific daylight time, an experimental, amateur-built Skybolt airplane, N300SB, was substantially damaged when it was involved in an accident near Corvallis, Oregon. The pilot and passenger were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The father of the passenger, who was the owner, reported that his son had just purchased the airplane, that a prepurchase inspection was conducted, and that “everything looked good.” He said his son asked the pilot to fly with him because he had extensive experience in similar airplanes. The flight included normal maneuvers and several touch-and-go landings with no issues. However, after the last landing and as he was taxiing the airplane back to the ramp, the left main landing gear (MLG) collapsed. Examination of the MLG truss structure, which is welded to the fuselage, revealed substantial damage to the fuselage frame structure. Examination also revealed that a weld joint where the truss mounts to the fuselage was cracked and broken. Rust was noted around the weld area, and it appeared that a previous crack had been repaired. The father reported that the area of the failure was hidden behind the bungee and was not visible during the prepurchase inspection.

Aircraft

Registration
N300SB
Reported as
Schneider K/Cook C SC Skybolt (NO SERIES)
Category
Airplane, amateur-built
Serial number
001
Built
1993
Damage
Substantial damage
Flight
Personal · Part 91
Airworthiness certificate
Special, Experimental (Special)
Departed
CVO · Corvallis, OR
Destination
CVO · Corvallis, OR
Airport
CVO · Corvallis Muni

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
74
Injuries
None
Certificate
Private
Airplane ratings
Single-engine land
Medical
Unknown
Seat
Rear
Restraint
5-point

Weather

Conditions
Visual (VMC) · Day
Wind
20° at 9 knots, gusting 16
Visibility
10 statute miles
Lowest ceiling
None
Temperature
91 °F, dew point 45 °F
Altimeter
30.07 inHg
Observed at
KCVO

Docket · 1

The files NTSB released with the investigation on March 3, 2021, on NTSB’s docket system: statements, records, photos and specialists’ reports. 117 KB in all.