ANC16LA021

NTSB accident investigation · Jim Riggs AK Ridge Runner · Wasilla, AK · April 23, 2016

Accident · No injuriesLimited investigationFinal report
Date
April 23, 2016, 14:45 local (22:45 UTC)
Place
Wasilla, AK
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Takeoff
Aircraft
N1549MJim Riggs AK Ridge Runner
Defining event
Takeoff: Loss of engine power (partial)
Weather
Visual (VMC) · Day
Status
Completed · report December 12, 2016
Report
Approved by Office Director
NTSB office
Alaska Regional Office
Parties
FAA Anchorage FSDO
FAA report
20160423024539A
Case key
93103

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 NTSB’s determination of the probable cause, and any contributing factors.

The loss of engine power for reasons that could not be determined because postaccident examination of the airframe and engine did not reveal any mechanical malfunctions or failures that would have precluded normal operation.

Findings · 1

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings.

Analysis

The light sport pilot was departing uphill from a 2,000-ft-long by 200-ft-wide gravel-covered runway, which was surrounded by trees. He said that, as the airplane approached midfield, it became airborne and the engine "sputtered," so he elected to abort the takeoff. After the airplane touched down, he was unable to stop it before striking a stand of trees at the end of the runway. The airplane sustained substantial damage to the right wing. A maintenance technician's postaccident examination of the airframe and engine revealed no mechanical malfunctions or failures that would have precluded normal operation. An aviation weather reporting station located 2 miles southeast of the accident site reported weather conditions about the time of the accident that were conducive for light to moderate carburetor icing at any engine power setting; however, the investigation could not determine whether carburetor icing caused the loss of engine power.

Factual narrative

On April 23, 2016, about 1445 Alaska daylight time, an amateur built, light sport, experimental AK Ridge Runner airplane, N1549M, sustained substantial damage during an aborted takeoff following a partial loss of engine power from Lincoln Village Airpark, Wasilla, Alaska. The airplane was being operated by the pilot as a personal flight under the provisions of 14 Code of Federal Regulations Part 91, when the accident occurred. The light sport pilot, the sole occupant of the airplane, was not injured. Visual meteorological conditions prevailed, and no flight plan was filed. In a telephone interview with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) on April 25, the pilot said that he was departing, uphill, from a 2,000-foot-long by 200-foot-wide gravel runway, which was surrounded by trees. He said that during the takeoff run, as the airplane approached midfield, it became airborne and the engine "sputtered" so he elected to abort the takeoff. He explained that after the airplane touched down again, he was unable to get the airplane stopped before striking a stand of trees at the end of the runway. The airplane sustained substantial damage to the right wing. The airplane was equipped with a Continental Motors, O-200 series engine. During a follow-up telephone interview with the NTSB IIC on July 8, the accident pilot reported he and his maintenance technician's postaccident inspection of the airplane revealed no mechanical problems that would have precluded normal operations. He said that on the day of the accident, just before takeoff, he taxied the airplane to the end of the runway with the carburetor heat in the off position. When he reached the end of the runway, he momentarily applied carburetor heat, and then turned it off just before applying takeoff power. He added that loss of engine power was likely was due to carburetor icing. The closest weather reporting facility was the Wasilla Airport, about 5 miles south of the accident site. The 1416 weather observation from the Wasilla Airport was reporting, in part: Wind 180 degrees (true) at 5 knots; visibility 10 statute miles; clouds and sky condition, 8,500 overcast; temperature, 59 degrees F; dew point 32 degrees F; altimeter 29.61 inHg. According to a carburetor icing probability chart, the conditions at the time of the accident were conducive for light to moderate carburetor icing at any engine power setting.

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident.

Aircraft

Registration
N1549M
Reported as
Jim Riggs AK Ridge Runner
Category
Airplane, amateur-built
Serial number
001
Built
2015
Airframe hours
22
Engine
Continental Motors O-200, 100 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Airworthiness certificate
Special, Experimental light sport (Special)
Last inspection
Unknown · August 18, 2016 · 22 hours before
Departed
89AK · Wasilla, AK
Destination
89AK · Wasilla, AK
Airport
89AK · Lincoln Village Airpark, runway 16, 2,000 × 200 ft, gravel

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
60
Injuries
None
Certificates
Student, Sport Pilot
Seat
Front
Flight hours
94 total · 22 in this make and model

Weather

Conditions
Visual (VMC) · Day
Wind
190° at 3 knots
Visibility
10 statute miles
Lowest ceiling
8,500 ft overcast
Temperature
59 °F, dew point 32 °F
Altimeter
29.61 inHg
Observed at
PAWS, 5 nm away

Docket · 3

The files NTSB released with the investigation on August 25, 2016, on NTSB’s docket system: statements, records, photos and specialists’ reports. 1.6 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.