CEN13LA220

NTSB accident investigation · Walker Phil RV-6A · Spearfish, SD · April 4, 2013

Accident · Minor injuriesLimited investigationFinal report
Date
April 4, 2013, 16:40 local (22:40 UTC)
Place
Spearfish, SD
Injuries
2 minor
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N525PWWalker Phil RV-6A
Defining event
Enroute: Loss of engine power (total)
Weather
Visual (VMC) · Day
Status
Completed · report December 11, 2013
Report
Approved by Office Director
NTSB office
Central Region
Parties
FAA FSDO
FAA report
20130404004939A
Case key
86597

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 coil-distributor wire loosening in flight, which rendered the ignition system inoperative and subsequently caused the loss of engine power.

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.

Ignition system: dist (ignition harness)Aircraft › Aircraft power plant · Not specifiedWalker Phil RV6A: 1 caseAll aircraft: 5 casesProbable cause
Power plantAircraft › Aircraft power plant · FailureWalker Phil RV6A: 1 caseAll aircraft: 198 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

While climbing through 6,000 feet, the engine suddenly lost power. The pilot stated that, although he subsequently switched on the auxiliary fuel pump and ignition system, the engine did not restart; therefore, he executed a forced landing to a nearby pasture. The nose landing gear collapsed during the landing, and the airplane came to rest inverted. Examination of the automotive engine, which had been adapted for aviation use, found that the coil-distributor wire had loosened and was not connected to the coil. It is likely that the wire came loose during flight, which rendered the automotive ignition system inoperative and caused the engine to lose power.

Factual narrative

On April 4, 2013, about 1640 mountain daylight time, an RV-6A airplane, N525PW, experienced a loss of engine power and conducted a forced landing near Spearfish, South Dakota. The private rated pilot and flight instructor received minor injuries and the airplane was substantially damaged. The airplane was registered to and operated by a private individual under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed for the flight that operated without a flight plan. The flight originated from the Black Hills Airport – Clyde Ice Field, Spearfish, South Dakota, about 1630. According to the pilot, he had recently purchased the airplane and was flying the airplane back to his home airfield. After stopping at an en route airport for fuel, they departed, and were climbing through 6,000 feet when the engine suddenly lost power. The pilot added that he switched on the auxiliary fuel pump and ignition system; however, the engine did not restart. He then selected a pasture for the forced landing. During landing, the nose gear collapsed and the airplane came to rest inverted. The responding Federal Aviation Administration (FAA) inspector examined the airplane on site and noted that the airplane’s fuselage and vertical stabilizer sustained substantial damage during the accident. The airplane was equipped with an automotive Chevrolet 4.6L engine adapted for aviation use. Further examination of the engine revealed that the carburetor’s air filter was dirty and partly clogged. Additionally, a wire that runs from the coil to the distributor was found disconnected from the coil terminal. The wire and distributor were the automotive type and had the traditional terminal male/female plug arrangement, without an additional locking mechanism.

Aircraft

Registration
N525PW
Reported as
Walker Phil RV-6A
Category
Airplane, amateur-built
Serial number
525
Engine
Chevy 4.6L, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Airworthiness certificate
Special, Experimental (Special)
Departed
Spearfish, ND
Destination
Spearfish, ND

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
33
Injuries
Minor
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 3, Without waivers/limitations
Last flight review
May 8, 2012
Seat
Left
Flight hours
291 total · 1 in this make and model · 272 as pilot in command · 39 in the last 90 days · 15 in the last 30 days
Role
Flight instructor

Weather

Conditions
Visual (VMC) · Day
Wind
100° at 17 knots, gusting 22
Visibility
10 statute miles
Lowest ceiling
None
Temperature
54 °F, dew point 25 °F
Altimeter
29.98 inHg
Observed at
KSPF

Docket · 3

The files NTSB released with the investigation on July 31, 2013, on NTSB’s docket system: statements, records, photos and specialists’ reports. 1.5 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.