# NTSB DEN06LA011: Piper PA-18-150, N4055Z, Cortez, CO, October 26, 2005 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: October 26, 2005, 15:45 local (22:45 UTC) - Place: Cortez, CO - Coordinates: 37.303054, -108.628051 - Nearby events: https://openairdocs.org/map.md?lat=37.3031&lon=-108.6281&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report April 25, 2006 - Report: Approved by Office Director - Parties: Flight Standards District Office - NTSB case key (mKey): 62642 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN06LA011 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/62642/pdf - Page: https://openairdocs.org/ntsb/DEN06LA011 ## Probable cause the pilot's failure to maintain directional control of the airplane, resulting in a ground loop. Contributing factors were the excessive descent rate, the obstacle (horse), the high density altitude, and the tailwind. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - in flight, go-around (vfr) - object - animal(s) (contributing factor) - descent - excessive, pilot in command (contributing factor) - directional control - not maintained, pilot in command (cause) - weather condition - high density altitude (contributing factor) - weather condition - tailwind (contributing factor) - Loss of control - on ground/water, landing - flare/touchdown - stall/mush - inadvertent, pilot in command (contributing factor) ## Analysis The pilot said that he was attempting to land in a pasture next to his home when he noticed a horse near the approach end. He elected to land long to avoid the horse but realized there was not enough pasture remaining. He attempted a go-around and added full power but could not arrest the sink rate. He decided to land the airplane in the remaining pasture. He landed with power in a nose high attitude at stall speed. The left wing struck the ground, causing the airplane to rotate 180 degrees to the left, and the right wingtip dragged along the ground. The pilot said he was not use to the extra weight of a full fuel load and carrying a rear seat passenger with a 5 knot tailwind. Density altitude at the time of the accident was calculated to be 7,741 feet mean seal level (msl). ## Factual narrative On October 26, 2005, approximately 1545 mountain standard time, a Piper PA-18-150, N4055Z, piloted by a private pilot, was substantially damaged when it ground looped during landing near Cortez Municipal Airport (CEZ), Cortez, Colorado. Visual meteorological conditions prevailed at the time of the accident. The personal flight was being conducted under the provisions of Title 14 CFR Part 91 without a flight plan. The pilot and passenger were not injured. The local flight originated from the pilot's private airstrip, near CEZ, approximately 1430. According to a telephone interview with the pilot and the accident report he subsequently submitted, he was attempting to land at his home when he noticed a horse near the approach end of the runway. He elected to land long to avoid a horse but then realized insufficient runway remained. He attempted a go-around and added full power but could not arrest the sink rate. He decided to land the airplane on the runway remaining. He landed with power applied in a nose high attitude right at stall speed. The left wing struck the ground, causing the airplane to rotate 180 degrees to the left and dragging the right wingtip dragged along the ground. The pilot said he was unfamiliar with mountain flying conditions in Cortez, Colorado, (5,918 feet msl) as he had done most of his flying near sea level in Alaska. He said he had just filled the fuel tanks to capacity, and the extra weight of the fuel and the rear seat passenger made the airplane heavier than what he was accustom. He also said there was a 5 knot tailwind during the landing. Postaccident examination disclosed a broken left wing spar. The right wingtip was scratched. Density altitude at the time of the accident was calculated to be 7,741 feet mean seal level (msl). ## Aircraft - Registration: [N4055Z](https://openairdocs.org/aircraft/N4055Z), registered now, S/N 18-8060 (OpenAirDocs) - Reported make and model: Piper PA-18-150 - 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: 18-8060 - Airframe hours: 3603 - Engines: Lycoming O-320-A2A 180 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Martin M Lawrence - Airworthiness certificate: Standard, Utility - Last inspection: Annual, September 1, 2005, 3 hours before - Departed: Cortez, CO - Destination: Cortez, CO ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 48; injuries: none; private; airplane ratings: single-engine land; medical: class 2, with waivers/limitations; last flight review March 1, 2004; seat: front; flight hours: 1,400 total, 750 in this make and model, 1,300 as pilot in command, 50 in the last 90 days, 3 in the last 30 days - Other flight crew; age 75; injuries: none; private; airplane ratings: single-engine sea, single-engine land; medical: unknown, unknown; seat: rear; flight hours: 310 total ## Weather - Conditions: Visual (VMC), Day - Wind: 310° at 11 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 63 °F, dew point 39 °F - Altimeter: 30.02 inHg - Observed at: CEZ ## 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 20051026025769A](https://openairdocs.org/incident/20051026025769A), Oct 26, 2005: Piper PA18150, Cortez, CO, Substantial damage. (-23) The pilot was landing on a grass runway in a pasture field at approximately 6,200 feet MSL. Pilot had applied full flaps in preparation for landing when… ## Other investigations on N4055Z (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 ANC97LA039](https://openairdocs.org/ntsb/ANC97LA039), Mar 27, 1997: Piper PA-18 (N4055Z), Chugiak, AK, substantial damage. Probable cause: the pilot's selection of an unsuitable landing site. - [NTSB MKC65A0079](https://openairdocs.org/ntsb/MKC65A0079), Jun 26, 1965: Piper PA-18 (N4055Z), Modoc, KS, destroyed, 1 fatal 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.