CEN11LA361

NTSB accident investigation · Flournoy Martin R Flournoy MR S1S · Colorado Springs, CO · May 22, 2011

Accident · No injuriesLimited investigationFinal report
Date
May 22, 2011, 16:30 local (22:30 UTC)
Place
Colorado Springs, CO
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Landing
Aircraft
N457CFFlournoy Martin R Flournoy MR S1S
Defining event
Landing-landing roll: Landing gear collapse
Weather
Visual (VMC) · Day
Status
Completed · report November 17, 2011
Report
Approved by Office Director
NTSB office
Central Region
Parties
FAA/FSDO
FAA report
20110522008749A
Case key
79252

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 pilot’s loss of directional control during the landing rollout due to failure of the tailwheel assembly for undetermined reasons.

Findings · 2

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.

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 he made a normal touchdown, but during the rollout the airplane began to yaw to the left. He attempted to correct his loss of directional control by applying full right rudder and right brake. Despite his efforts to straighten the airplane's path, the airplane began to bounce/skip to the side and subsequently ground looped. During the impact sequence, the lower right wing tip, aileron and aft section of the fuselage sustained substantial damage. Postaccident examination of the airplane revealed that the tailwheel spring attach bolt had pulled through the fuselage structure where it was mounted. The bolt was intact and there was no obvious damage to the threads. It could not be determined why the bolt separated prior to the accident.

Factual narrative

On May 22, 2011, at 1630 mountain daylight time, N457CF, an experimental Flournoy MR S1S airplane, ground-looped during landing on Runway 15 at Meadowlake Airport (KFLY), Colorado Springs, Colorado. The airplane was registered to and operated by the commercial rated pilot, who was not injured. Visual meteorological conditions prevailed and no flight plan was filed for the local flight conducted under 14 CFR Part 91. According to the pilot, after a normal touchdown, he felt the tail drop about 6-inches followed by a loud grinding noise. As the airplane began to decelerate, it began to yaw to the left. The pilot applied full right rudder and right brake, but was unable to stop the yaw to the left. The airplane continued to rotate to the left and began to bounce/skip to the side and roll. The lower right wing struck the ground and the engine came to an abrupt stop. The pilot reported that the right main landing gear strut, entire brake assembly, wheel, tire, and wheel pant were damaged. The lower right wing tip and aileron sustained substantial damage from impacting the ground. The tailwheel separated from the airplane and there was substantial damage to the rudder and aft section of the fuselage. The propeller was also damaged. An inspector with the Federal Aviation Administration (FAA) performed an examination of the airplane and discovered that the tailwheel spring attach bolt had pulled through the fuselage structure where it was mounted. The bolt was intact and there was no obvious damage to the threads. It could not be determined as to why the bolt separated. Weather at Meadowlake airport at 1630 was reported as clear skies, visibility 10 miles, and wind from 100 degrees at 5 knots.

Aircraft

Registration
N457CF
Reported as
Flournoy Martin R Flournoy MR S1S
Category
Airplane, amateur-built
Serial number
08
Airframe hours
808
Engine
Lycoming O&VO-360 SER, 180 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Operator
Matt Tanner Aviation LLC
Registered owner
Matt Tanner Aviation LLC
Airworthiness certificate
Special, Experimental (Special); Standard, Normal
Last inspection
Condition · October 1, 2010
Departed
KFLY · Colorado Springs, CO
Destination
KFLY · Colorado Springs, CO
Airport
KFLY · Meadow Lake, runway 15, 6,000 × 60 ft, asphalt

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
31
Injuries
None
Certificate
Commercial
Airplane ratings
Single-engine land
Instrument ratings
Airplane
Medical
Class 3, Without waivers/limitations
Last flight review
February 1, 2011
Seat
Single
Flight hours
3,600 total · 370 in this make and model · 3,500 as pilot in command · 150 in the last 90 days · 60 in the last 30 days · 1 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
100° at 5 knots
Visibility
10 statute miles
Temperature
70 °F, dew point 39 °F
Altimeter
29.97 inHg
Observed at
KFLY

Docket · 2

The files NTSB released with the investigation on October 3, 2011, on NTSB’s docket system: statements, records, photos and specialists’ reports. 324 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.