ANC08FA079

NTSB accident investigation · Piper PA-18 · Wasilla, AK · June 30, 2008

Accident · FatalField investigationFinal report
Date
June 29, 2008, 16:50 local (Jun 30, 2008, 00:50 UTC)
Place
Wasilla, AK
Injuries
1 fatal, 1 minor
Damage
Substantial damage
Phase of flight
Landing
Aircraft
N2581PPiper PA-18
Defining event
Landing: Loss of control in flight
Weather
Visual (VMC) · Day
Status
Completed · report July 28, 2009
Report
Approved by Office Director
NTSB office
Alaska Regional Office
Parties
Federal Aviation Administration
FAA report
20080629840919A
Case key
68350

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 directional control while landing in a gusty crosswind.

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: directional controlAircraft › Aircraft oper/perf/capability · Not attained/maintainedPiper PA-18A 150: 10 casesAll aircraft: 3,958 casesProbable cause
Use of equip/info: aircraft controlPersonnel issues › Task performance · PilotPiper PA-18A 150: 18 casesAll aircraft: 9,295 casesProbable cause
Wind: crosswindEnvironmental issues › Conditions/weather/phenomena · Effect on operationPiper PA-18A 150: 3 casesAll aircraft: 1,008 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 private pilot and passenger were returning to the pilot's private airstrip after a local personal flight. A witness said that about 20 minutes after the airplane had departed, it returned overhead, circled the airstrip once, then began an approach for landing to the south, which required a correction for a left crosswind. As the airplane passed over the approach end of the airstrip, its approach became unstable and it drifted to the right, towards a stand of large trees that bordered the airstrip. Just before the airplane touched down, the engine power increased significantly, the nose pitched up, and it began a steep climb. The witness said that the airplane's right wing struck a 75-foot-tall tree, which pivoted the airplane to the right, and it descended nose first into dense woods. Witnesses stated that at the time of the accident, there were gusty winds between 25 and 30 knots, with rapid direction changes. Examination of the airplane did not disclose any preimpact mechanical malfunction.

Factual narrative

HISTORY OF FLIGHT On June 29, 2008, about 1650 Alaska daylight time, a tundra tire-equipped Piper PA-18 airplane, N2581P, sustained substantial damage when it collided with a stand of trees during an attempted go-around while landing at a private airstrip, about 6 miles east of Wasilla, Alaska. The airplane was being operated as a visual flight rules (VFR) personal flight under the provisions of 14 Code of Federal Regulations Part 91, when the accident occurred. The private pilot died at the scene, and the one passenger sustained minor injuries. Visual meteorological conditions prevailed, and no flight plan was filed for the local area flight. According to family members, the flight originated from the accident airstrip about 1630. During an on scene interview with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) on June 29, about 1930, a witness to the accident who was a family friend of the pilot, reported that the purpose of the flight was to show the passenger some Alaskan scenery. The witness said that about 20 minutes after the airplane had departed, it returned overhead, circled the airstrip once, and then began an approach for a landing to the south, which required a correction for a left crosswind. He reported that as the airplane passed over the approach end of the airstrip, its approach became unstable, and it drifted to the right, towards a stand of large trees that bordered the airstrip. He said that just before the airplane touched down, the engine power increased significantly, the nose pitched up, and it began a steep climb. The witness said that the airplane's right wing struck a 75-foot tall tree, which pivoted the airplane to the right, and it descended nose first into dense woods. The witness noted that at the time of the accident, there were gusty winds. He said that the windsock, which is situated at the approach end of the airstrip, indicated rapid direction changes just before the accident. During an interview with the NTSB IIC on June 29, about 2230, after being released from a local hospital, the passenger reported that throughout the 20-minute flight, the airplane encountered intermittent turbulence. She said that as the airplane neared the airstrip at the completion of the flight, the pilot told her that the turbulence might get worse as the airplane got closer to the airstrip. She said that as the airplane continued on the approach, and it descended below the tree line, the left wing lifted, and the airplane drifted to the right, towards a large stand of trees. She said that the pilot added full engine power, in conjunction with full left aileron and aft elevator, but the right wing and the right side of the fuselage collided with a large tree, and the airplane descended nose down into the forest. PERSONNEL INFORMATION The pilot held a private pilot certificate with an airplane single-engine land rating. His most recent third-class medical certificate was issued on May 8, 2006, andcontained the limitation that he wear corrective lenses. No recent personal flight records were located for the pilot, and the aeronautical experience listed on page 3 of this report was obtained from FAA records on file in the Airman and Medical Records Center in Oklahoma City, Oklahoma. On the pilot's application for medical certificate, dated May 8, 2006, he indicated his total aeronautical experience was 1,000.0 flight hours, of which 15 flight hours were accrued in the previous 6 months. AIRCRAFT INFORMATION The airplane had a total time in service of 4,864.9 flight hours at the time of the accident. Examination of the maintenance records revealed that the last annual inspection of the airframe and engine was on October 19, 2007, about 10.7 flight hours before the accident. METEOROLOGICAL INFORMATION The closest official weather observation station is Wasilla, Alaska, about 8 miles west of the accident site. At 1636, an Aviation Routine Weather Report (METAR) was reporting in part: Wind, 260 degrees at 9 knots; visibility, 10 statute miles; clouds and sky condition, 11,000 feet broken; temperature, 55 degrees F; dew point, 41 degrees F; altimeter, 30.19 inHg. COMMUNICATIONS There were no reports of communications with the accident airplane. WRECKAGE AND IMPACT INFORMATION On June 29, the NTSB IIC, and an FAA airworthiness inspector from the Anchorage Flight Standards District Office (FSDO), responded to the accident site and examined the wreckage. All of the airplane's major components were found at the accident site. The accident site was in an area of hilly, tree and tundra-covered terrain adjacent to the accident pilot's private airstrip. The wreckage site was about 500 feet from the approach end of the 1,800 foot long sod-covered airstrip, and about 150 feet west of the airstrip centerline. The entire airstrip was surrounded by 75 to 100 feet tall Birch trees. The airplane collided with a stand of trees about 75 feet tall. The airplane wreckage came to rest nose down, and was suspended by several broken and toppled trees. Various small tree sections around the wreckage displayed sharp cuts orientated on about a 45-degree angle to the vertical axis of each section. These segments averaged about 3 inches in diameter, and were between 10 to 15 inches long. Each end of the cut limbs were sliced at parallel angles to the long axis of the section, each resembling a parallelogram. All of the signatures were consistent with propeller strikes. The airplane's forward cabin structure, engine cowling, and windshield "V" brace, were crushed and buckled inward. The primary crush zones extended from the firewall area back to about the forward door post, and encompassed the pilot's cockpit area. An 8-inch diameter Birch tree sliced through the airplane's windscreen and overhead greenhouse, which struck the pilot. The outboard half of the left wing had significant leading edge aft crushing, with more crushing evident along the lower portion of theoutboard edge. The right wing had leading edge aft crushing. Both wing lift struts assemblies remained attached to their respective wing and fuselage attach points. The aft portion of the tail assembly and empennage remained attached to the fuselage. The vertical stabilizer, elevator, and rudder sustained impact damage, but remained attached. The flight control surfaces remained connected to their respective attach points. Flight control system cable continuity was established from the control surfaces to the point of impact related damage. Both propeller blades remained attached to the engine crankshaft. Both propeller blades had extensive leading edge gouging, "S" bending, torsional twisting, and aft bending of about 30 degrees. There were no preaccident mechanical problems discovered with the airplane's engine or flight controls during the NTSB IIC's on-scene wreckage examination. MEDICAL AND PATHOLOGICAL INFORMATION A postmortem examination of the pilot was conducted under the authority of the Alaska State Medical Examiner, 4500 South Boniface Parkway, Anchorage, Alaska, on June 30, 2008. The cause of death for the pilot was attributed to blunt force, traumatic injuries. The FAA's Civil Aeromedical Institute (CAMI) toxicological examination was negative for alcohol or drugs. In addition, an unspecified level of irbesartan was detected in the pilot's urine and blood. Irbesartan is a prescription medication commonly used to treat high blood pressure. WRECKAGE RELEASE The Safety Board released the wreckage, located at accident site, to the owner's representatives on June 29, 2008. The Safety Board retained no parts or components.

Aircraft

Registration
N2581P
Reported as
Piper PA-18
Category
Airplane
Serial number
18-4323
Airframe hours
4,865
Engine
Lycoming O-360, 180 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Operator
Robert J. Gilmore
Registered owner
Glimore Robert J
Airworthiness certificate
Standard, Normal
Last inspection
Annual · October 19, 2007 · 11 hours before
Departed
Wasilla, AK
Destination
Wasilla, AK
Airport
runway 18, 1,800 × 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
55
Injuries
Fatal
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 3, With waivers/limitations
Last flight review
June 21, 2007
Seat
Front
Toxicology
Performed
Flight hours
1,000 total · 15 in the last 90 days · 1 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
260° at 9 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
70 °F
Observed at
PAWS, 8 nm away

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.