CEN14LA045

NTSB accident investigation · Sutphin Rans S-12 · French Lick, IN · October 11, 2013

Accident · No injuriesLimited investigationFinal report
Date
October 11, 2013, 17:00 local (21:00 UTC)
Place
French Lick, IN
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Approach
Aircraft
N8028WSutphin Rans S-12
Defining event
Approach-VFR pattern downwind: Loss of control in flight
Weather
Visual (VMC) · Day
Status
Completed · report February 3, 2014
Report
Approved by Office Director
NTSB office
Central Region
Parties
Federal Aviation Administration, Indianapolis FSDO
FAA report
20131011020019A
Case key
88395

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 while in a steep turn, which resulted in an aerodynamic stall/mush at a low altitude.

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 parameters: airspeedAircraft › Aircraft oper/perf/capability · Not attained/maintainedSutphin John E RANS S-12: 2 casesAll aircraft: 1,681 casesProbable cause
Performance/control parameters: angle of attackAircraft › Aircraft oper/perf/capability · Not attained/maintainedSutphin John E RANS S-12: 1 caseAll aircraft: 990 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

After a short local flight, which consisted of several uneventful turns, the pilot decided to return to the airport for a landing. He reported that the airplane started to lose altitude as he made a right turn to enter the downwind leg of the landing pattern. The pilot responded by advancing the throttle to maximum engine power; however, he was unable to increase airspeed or arrest the descent before the airplane collided with a tree. The passenger reported that the airplane appeared to lose altitude as the pilot performed a steep right turn over a wooded area southwest of the airport. A postaccident airframe examination and engine test run revealed no evidence of a mechanical malfunction or failure that would have precluded normal operation. Wind at the nearest aviation weather reporting station about the time of the accident were calm. The pilot's inability to arrest the airplane's descent or increase its airspeed during a steep turn in the airport traffic pattern, despite his application of full engine power, is consistent with the airplane having encountered an aerodynamic stall.

Factual narrative

On October 11, 2013, at 1700 eastern daylight time, an experimental amateur-built Sutphin model Rans S-12 airplane, N8028W, was substantially damaged when it collided with trees while maneuvering near the French Lick Municipal Airport (FRH), French Lick, Indiana. The commercial pilot and passenger were not injured. The airplane was registered to and operated by the pilot, under the provisions of 14 Code of Federal Regulations Part 91, without a flight plan. Day visual meteorological conditions prevailed for the local area flight that had departed FRH about 1640. The pilot reported that the accident occurred during a demonstration flight for a potential buyer of the airplane. After a short local area flight, which consisted of several uneventful turns, the pilot decided to return to the airport for a landing. He reported that the airplane started to lose altitude while in a right turn to enter the downwind leg for runway 8. The pilot responded by advancing the engine to maximum power; however, he was unable to arrest the descent or increase airspeed before the airplane collided with a tree. The right wing was substantially damaged during the impact. The pilot reported no preaccident malfunctions or failures with the airplane that would have prevented normal operation. The passenger reported that the airplane appeared to lose altitude as the pilot performed a steep right turn over a wooded area southwest of the airport. The passenger reported that the pilot increased engine power after he leveled out of the steep turn; however, the airplane continued to descend into the trees. The airplane came to rest suspended in a tree about 60 feet above the ground. The passenger stated that the engine continued to run at an idle power setting following the accident until the pilot turned off the magneto switches. A postaccident examination was completed by inspectors with the Federal Aviation Administration (FAA) after the wreckage had been recovered from the accident site. The FAA examination confirmed flight control continuity from the individual flight control surfaces to their respective cockpit controls. The fuel tank contained about 3 gallons of fuel and there was fuel in the supply line to the carburetors. An operational engine test run established that there were no mechanical or electrical anomalies with the engine. The FAA examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. The nearest aviation weather reporting station was located at Huntingburg Airport (HNB), Huntingburg, Indiana, about 21 miles southwest of the accident site. At 1655, the HNB automated surface observing system reported: calm wind conditions, visibility 10 miles, sky clear, temperature 24 degrees Celsius, dew point 12 degrees Celsius, and an altimeter setting of 30.03 inches of Mercury.

Aircraft

Registration
N8028W
Reported as
Sutphin Rans S-12
Category
Airplane, amateur-built
Serial number
0894513
Built
1995
Engine
Rotax 582, 64 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Airworthiness certificate
Special, Experimental (Special)
Last inspection
Condition · April 22, 2013
Departed
FRH · French Lick, IN
Destination
FRH · French Lick, IN
Airport
FRH · French Lick Municipal Airport, runway 08, 5,500 × 100 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
65
Injuries
None
Certificate
Commercial
Airplane ratings
Single-engine land
Medical
Class 2, With waivers/limitations
Seat
Left
Restraint
3-point
Flight hours
5,000 total · 10 in this make and model

Weather

Conditions
Visual (VMC) · Day
Wind
Calm
Visibility
10 statute miles
Lowest ceiling
None
Temperature
75 °F, dew point 54 °F
Altimeter
30.03 inHg
Turbulence
Unknown
Observed at
HNB, 21 nm away

Docket · 5

The files NTSB released with the investigation on December 18, 2013, on NTSB’s docket system: statements, records, photos and specialists’ reports. 1.1 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 N8028W · 1

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