# NTSB ANC03LA111: Piper PA-18-160, N4418Z, Skwentna, AK, September 8, 2003 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: September 7, 2003, 20:10 local (Sep 8, 2003, 04:10 UTC) - Place: Skwentna, AK - Coordinates: 61.716667, -152.78334 - Nearby events: https://openairdocs.org/map.md?lat=61.7167&lon=-152.7833&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: Serious injuries - Injuries: 1 serious, 1 minor - Status: Completed, report April 28, 2004 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - Parties: Federal Aviation Administration - NTSB case key (mKey): 57892 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC03LA111 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/57892/pdf - Page: https://openairdocs.org/ntsb/ANC03LA111 ## Probable cause The pilot's failure to maintain airspeed, which resulted in an inadvertent stall, and subsequent in-flight collision with terrain. A factor associated with the accident was a downdraft. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - in flight, maneuvering - weather condition - downdraft (contributing factor) - airspeed(vs) - not maintained, pilot in command (cause) - stall - inadvertent, pilot in command - In flight collision with terrain/water, descent - uncontrolled - terrain condition - ground ## Analysis The private pilot was attempting to fly over a 1,200 foot long, gravel-surfaced site before landing. He reported that as he maneuvered the airplane for the fly over, he applied 10 degrees of wing flaps, and a "downdraft came over the wings and stalled them both... ." The airplane subsequently struck the ground in a nose down attitude, and came to rest about 200 feet from the approach end of the intended landing site. The airplane sustained structural damage to the wings, fuselage, and empennage. The pilot noted that there were no preaccident mechanical anomalies with the airplane. ## Factual narrative On September 7, 2003, about 2010 Alaska daylight time, a wheel-equipped Piper PA-18-160 airplane, N4418Z, sustained substantial damage following a loss of control while maneuvering over a remote off-airport site, located approximately 25 miles southwest of Skwentna, Alaska. The private pilot/airplane owner sustained serious injuries, and the sole passenger sustained minor injuries. The Title 14, CFR Part 91 personal flight operated in visual meteorological conditions without a flight plan. The flight departed from a private airstrip located in Wasilla, Alaska, about 1830. In the NTSB Pilot/Operator Accident Report (form 6120.1) submitted by the pilot, he reported he intended to fly over a 1,200 foot long, gravel-surfaced site before attempting to land. He said that as he maneuvered the airplane for the fly over, he applied 10 degrees of wing flaps, and a "downdraft came over the wings and stalled them both..." Subsequently, the airplane struck the ground in a nose down attitude, and came to rest about 200 feet from the approach end of the intended landing site. The airplane sustained structural damage to the wings, fuselage, and empennage. The pilot noted that weather conditions at the time of the accident were, in part: Sky conditions and ceilings, clear; visibility, 20 statute miles; temperature, 50 degrees F; wind, calm. The pilot stated that there were no preaccident mechanical anomalies with the airplane. ## Aircraft - Registration: [N4418Z](https://openairdocs.org/aircraft/N4418Z), registered now, S/N 18-8753, built 1968 (OpenAirDocs) - Reported make and model: Piper PA-18-160 - Registry model: [Piper PA-18-150](https://openairdocs.org/model/piper-pa-18-150) (registry code 7101828) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 18-8753 - Engines: Lycoming O-320-A2B 160 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Clinton D. Swaney - Airworthiness certificate: Standard, Normal - Last inspection: Annual, May 20, 2003, 25 hours before - Departed: Wasilla, AK - Destination: Skwentna, AK ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 31; injuries: serious; private; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; last flight review November 19, 2002; seat: front; flight hours: 298 total, 25 in this make and model, 298 as pilot in command, 25 in the last 90 days, 11 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 20 statute miles - Lowest ceiling: none - Temperature: 50 °F ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 20030907025469A](https://openairdocs.org/incident/20030907025469A), Sep 7, 2003: Piper PA18150, Skwentna, AK, Substantial damage. (-23) According to the pilot, the aircraft was flown low over the unimproved strip to determine its suitability for landing. The landing was for the purpose of… ## Other investigations on N4418Z (2) From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. - [NTSB ANC00LA051](https://openairdocs.org/ntsb/ANC00LA051), Apr 29, 2000: Piper PA-18 (N4418Z), Seldovia, AK, substantial damage. Probable cause: The pilot's failure to maintain directional control of the airplane. A factor in the accident was an inadvertent ground swerve. - [NTSB ANC86FA071](https://openairdocs.org/ntsb/ANC86FA071), Jun 10, 1986: Piper PA-18 (N4418Z), Girdwood, AK, substantial damage From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.