# NTSB SEA07LA040: Tessier Avid Flyer, N93TT, Hillsboro, OR, December 30, 2006 - Type: NTSB accident investigation - Classification: Accident · Fatal · Limited investigation · Final report - Date: December 30, 2006, 09:50 local (17:50 UTC) - Place: Hillsboro, OR - Coordinates: 45.429164, -122.96083 - Nearby events: https://openairdocs.org/map.md?lat=45.4292&lon=-122.9608&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: Fatal - Injuries: 1 fatal - Status: Completed, report May 29, 2007 - Report: Approved by Office Director - Parties: Portland FSDO - NTSB case key (mKey): 65097 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA07LA040 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/65097/pdf - Page: https://openairdocs.org/ntsb/SEA07LA040 ## Probable cause The loss of engine power during maneuvering flight due to carburetor icing, and inadvertent flight into instrument meteorological conditions. Factors were the ambient weather conditions conducive to carburetor icing and fog. ## Analysis The pilot, who was flying to a location where he was going to meet family members for lunch, departed from an airport that was reporting clear skies, no precipitation, and nine miles visibility. About seven minutes after departure he encountered an area of solid undercast. The ambient conditions in the area made carburetor icing a strong possibility at both glide and cruise power, and soon after flying over the undercast the pilot experienced carburetor icing and his engine started to lose power. Although the aircraft's carburetor heat system was later found to be without anomaly, the pilot was unable to keep the engine running, and it eventually lost all power. He then was forced to descend through the thick layer of fog to attempt a forced landing in instrument meteorological conditions. During that attempted landing, the aircraft impacted the terrain, resulting in fatal injuries to the pilot. ## Factual narrative On December 30, 2006, approximately 0950 Pacific standard time, an experimental Tessier Avid Flyer impacted the terrain during an attempted engine-out landing about one mile west of Stark's Twin Oaks Airpark, Hillsboro, Oregon. The private pilot, who was the sole occupant, received fatal injuries, and the aircraft, which is owned and operated by the pilot, sustained substantial damage. The 14 CFR Part 91 personal pleasure flight, which departed Portland-Hillsboro Airport about 12 minutes prior to the accident, and was en route to Newberg, Oregon, was flying in an area with a solid undercast of fog. According to family members, the pilot and his wife were planning on meeting other family members in Newberg for lunch. He and his wife left their home about the same time, but she planned to drive to Newberg, and he planned on flying there. While driving to Newberg, the pilot's wife called him by cell phone to advise him that as she progressed toward Newberg she was encountering lots of thick fog. According to the controller at the Hillsboro Tower, the pilot departed Hillsboro Airport at 0938, and about seven minutes later reported that he was over Twin Oaks Airpark, and was trapped over a fog layer. He also reported that his engine was starting to lose power, and that he was going to attempt to make it back to Hillsboro Airport. About 70 seconds after the first transmission, the pilot reported that his engine had quit, and that he was "going down." The aircraft then descended through the fog and collided with the terrain. Because of the dense fog in the area, there were no witnesses to the ground impact. The investigation revealed that according to the DOT/FAA/CT-82/44 Carburetor Icing Probability Chart, that the pilot was operating in an ambient environment where serious carburetor icing could be expected to occur at both glide and cruise power (see Weather Information). The post accident inspection of the aircraft determined that there were no indications of any anomalies or shortcomings in the carburetor heat system. The Portland-Hillsboro Airport was reporting weather at 0953 as clear with 9 miles visibility. The temperature was 0 degrees C. The wind was calm. A further investigation revealed that the pilot had been taking medication for control of pain, and that he did not have a current FAA medical certificate. A forensic toxicology examination of specimens from the pilot determined that his blood contained 0.024 ug/ml of Codeine, 1.518 ug/ml of Tramadol, and a detectable level of Bisoprolol. The same examination determined that his urine contained 11.096 ug/ml of Codeine, 0.375 ug/ml of Morphine, and detectable levels of Bisoprolol, Tramadol, and Ibuprofen. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power, maneuvering - fuel system,carburetor - ice (cause) - weather condition - carburetor icing conditions (contributing factor) - Forced landing, emergency landing - In flight collision with terrain/water, emergency landing - vfr flight into imc - inadvertent, pilot in command (cause) - weather condition - fog (contributing factor) - terrain condition - ground ## Aircraft - Registration: [N93TT](https://openairdocs.org/deregistered/N93TT-2011-10-19), registration cancelled 2011-10-19, S/N 1134D, built 1993 (OpenAirDocs) - Reported make and model: Tessier Avid Flyer - Registry model: [Tessier Thomas G AVID FLYER](https://openairdocs.org/model/tessier-thomas-g-avid-flyer) (registry code 05622EC) (OpenAirDocs) - Registry engine: [Bombardier ROTAX (ALL)](https://openairdocs.org/engine/bombardier-rotax-all) (registry code 09050, reciprocating) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 1134D - Airframe hours: 288 - Engines: Rotax 582 UL 65 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Dale D. Wilson - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, August 1, 2006, 3 hours before - Departed: KHIO, Hillsboro, OR - Destination: 17S, Newberg, OR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 54; injuries: fatal; private; airplane ratings: single-engine land; last flight review August 1, 2004; seat: left; toxicology performed; flight hours: 336 total, 10 in this make and model ## Weather - Conditions: Instrument (IMC), Day - Wind: calm - Visibility: 9 statute miles - Lowest ceiling: none - Temperature: 32 °F, dew point 34 °F - Altimeter: 30.42 inHg - Observed at: KHIO ## 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 20061230026079A](https://openairdocs.org/incident/20061230026079A), Dec 30, 2006: Tessie AVIDFLYER, Hillsboro, OR, Destroyed, 1 fatal. (-23) N93TT departed Hillsboro airport (khio) flight to newberg (K17S). 7 minutes later pilot radioed Hillsboro tower and reported engine cutting out and was… 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.