CEN18CA291

NTSB accident investigation · Quad City Challenger · Oshkosh, WI · July 23, 2018

Accident · No injuriesData collectionFinal report
Date
July 23, 2018, 09:50 local (14:50 UTC)
Place
Oshkosh, WI
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Approach
Aircraft
N1666RQuad City Challenger
Defining event
Approach-VFR pattern final: Loss of control in flight
Weather
Visual (VMC) · Day
Status
Completed · report March 18, 2019
Report
Approved by Office Director
NTSB office
Central Region
FAA report
20180723017829A
Case key
97856

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 pilot’s failure to maintain adequate airspeed during the base to final turn and his exceedance of the airplane’s critical angle of attack, which resulted in an aerodynamic stall.

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.

Performance/control parametersAircraft › Aircraft oper/perf/capability · Not attained/maintainedHoltz Rodney R CHALLENGER II: 1 caseAll aircraft: 1,269 casesProbable cause
Object/animal/substance: fence/fence postEnvironmental issues › Physical environment · Contributed to outcomeHoltz Rodney R CHALLENGER II: 1 caseAll aircraft: 313 cases

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 airplane was landing on the ultralight field when the accident occurred. The pilot stated that she made a wide base to final turn because she was unsure about the placement of the runway. Although the pilot added power, the airplane entered a left descending turn until the left wing contacted the ground near the beginning of the runway's displaced threshold. The airplane then spun left and slid rearward on the ground until it contacted a chain-link fence. The pilot reported that there were no mechanical anomalies with the airplane that would have precluded normal operation. The pilot's statement, along with a ground-based video of the accident, revealed that the pilot failed to maintain adequate airspeed and exceeded the airplane's critical angle of attack during the base to final turn, which resulted in an aerodynamic stall.

Factual narrative

The pilot reported that she made a wide turn from base leg to final approach because she did not know exactly where the runway was placed. She stated she banked the airplane to line up with the runway and was still in a bank when the airplane approached the runway threshold. She added power to keep from getting too low, but the airplane contacted the ground and spun around, coming to a stop up against a chain-link fence.The left wing, rudder, and elevator sustained substantial damage. The pilot reported that there were no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation. The experimental amateur built airplane was landing on ultralight runway 33 during Experimental Aircraft Association (EAA) AirVenture when the accident occurred. The EAA AirVenture Notice to Airmen (NOTAM) contained a diagram showing the approach route for airplanes landing on runway 33. The procedure is to follow the northbound road at the east end of Ripple Road then make an approximate 30° left turn near the runway threshold to align with the runway. The west side of the northbound road is bordered by trees. The accident airplane contacted the ground near the beginning of the displaced threshold for the runway. The accident was captured on a ground-based video which showed the airplane in a left descending turn as it approached the runway. The airplane continued in the left turn until the left wing contacted the ground. The left main gear and nose gear then contacted the ground followed shortly thereafter by the right main gear. The airplane then slid rearward and spun to the left coming to rest after the tail contacted the fence. The airplane came to rest on a heading of 45°.

Aircraft

Registration
N1666R
Reported as
Quad City Challenger (II)
Category
Airplane, amateur-built
Serial number
CH2-0899-1897
Built
2008
Airframe hours
348
Damage
Substantial damage
Flight
Personal · Part 91
Airworthiness certificate
Special, Experimental (Special)
Last inspection
Annual · July 15, 2018
Departed
Y50 · Wautoma, WI
Destination
OSH · Oshkosh, WI
Airport
OSH · Wittman Rgnl, runway 33, 1,200 × 100 ft, grass/turf

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
50
Injuries
None
Certificates
Private, Flight instructor
Airplane ratings
Single-engine sea, Single-engine land
Medical
Class 3, With waivers/limitations
Last flight review
July 11, 2016
Seat
Front
Flight hours
874 total · 299 in this make and model · 798 as pilot in command · 50 in the last 90 days · 18 in the last 30 days · 1 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
350° at 6 knots
Visibility
10 statute miles
Lowest ceiling
5,000 ft broken
Temperature
72 °F, dew point 63 °F
Altimeter
29.96 inHg
Observed at
KOSH, 1 nm away

Docket · 5

The files NTSB released with the investigation on September 25, 2018, on NTSB’s docket system: statements, records, photos and specialists’ reports. 15.8 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.

Other investigations on N1666R · 1

Matched to the same aircraft by N-number and date.