# NTSB CEN18LA095: Henderson Thorp T 18, N600HH, Troy, MO, February 8, 2018 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: February 8, 2018, 11:52 local (17:52 UTC) - Place: Troy, MO - Coordinates: 38.912223, -91.033332 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=38.9122&lon=-91.0333&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Defining event: [Approach-VFR pattern final: Controlled flight into terr/obj (CFIT)](https://openairdocs.org/ntsb-events/120) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed, report February 5, 2019 - Report: Approved by Office Director - NTSB office: Central Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 96720 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN18LA095 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/96720/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=96720 - Page: https://openairdocs.org/ntsb/CEN18LA095 ## Probable cause The pilot's failure to maintain adequate clearance from trees while landing in crosswind conditions. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: crosswind correction](https://openairdocs.org/ntsb-findings/01062030): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Henderson THORP T-18, 1 case](https://openairdocs.org/ntsb-findings/01062030/cases.md?model=8951044), [All aircraft, 184 cases](https://openairdocs.org/ntsb-findings/01062030/cases.md) - [Action: incorrect action performance](https://openairdocs.org/ntsb-findings/02041015): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Henderson THORP T-18, 1 case](https://openairdocs.org/ntsb-findings/02041015/cases.md?model=8951044), [All aircraft, 1,386 cases](https://openairdocs.org/ntsb-findings/02041015/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Approach-VFR pattern final: Controlled flight into terr/obj (CFIT)](https://openairdocs.org/ntsb-events/120) (defining event); cases with it: [Henderson THORP T-18, 1 case](https://openairdocs.org/ntsb-events/120/sequence.md?model=8951044), [All aircraft, 1,074 cases](https://openairdocs.org/ntsb-events/120/sequence.md) ## Analysis During a personal flight, the private pilot reported that he made one pass over the runway, which was oriented east to west, and noted a crosswind from the southwest. During final approach, the pilot extended the flaps "one notch" to add "a little speed" to compensate for the crosswind. The pilot then looked down at the instrument panel to check the rate of descent; when he looked back outside, he saw a small tree limb near the airplane's right wing tip. The pilot made a left control input, but the right wing tip impacted the tree, and the airplane turned slightly to the right. The airplane impacted several other trees and then nosed down into the ground. The pilot reported no airplane mechanical malfunctions or failures. ## Factual narrative On February 8, 2018, at 1152 central standard time, an amateur-built T-18 airplane, N600HH, collided with trees and terrain during landing at Woodland Airstrip (MU89), Troy, Missouri. The private pilot, who was the sole occupant, sustained serious injuries and the airplane sustained substantial damage. The airplane was registered to and operated by the pilot under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed at the time of the accident and no flight plan had been filed. The flight departed Creve Coeur Airport (1H0), St. Louis, Missouri, about 1030. The pilot reported that upon arrival at MU89 he made one pass over runway 27 and noted a crosswind from 230° at 10 to 20 knots. The pilot continued into the traffic pattern for a full stop landing on runway 27. During final approach while aligned to the left side of the runway and about 90 mph, the pilot extended the flaps "one notch." The pilot added that he wanted a little speed due to the crosswind on final. The pilot looked down at the instrument panel to check the rate of descent and when he looked back outside he saw a small tree tip near the airplane's right wing tip. He initiated a left control input, but the right wing tip collided with the tree and the airplane turned slightly right. The airplane continued into several trees and then nosed down into the ground. The pilot reported that there were no airplane mechanical malfunctions or failures. The responding Federal Aviation Administration (FAA) inspector performed a postaccident examination of the airplane and accident site. There was evidence of broken tree limbs about 30 to 40 yards east of the main wreckage. The airplane came to rest next to a tree line in a nose low, vertical attitude (figure 1). Flight control continuity was confirmed and no preimpact anomalies were evident. Figure 1 – Accident airplane ## Aircraft - Registration: [N600HH](https://openairdocs.org/aircraft/N600HH), registered now, S/N 600, built 1974 (OpenAirDocs) - Reported make and model: HENDERSON THORP T 18 (UNDESIGNAT) - Registry model: [Henderson THORP T-18](https://openairdocs.org/model/henderson-thorp-t-18) (registry code 8951044) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 600 - Year built: 1974 - Airframe hours: 682 - Engines: Lycoming O-320 150 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, October 10, 2015 - Departed: 1H0, ST LOUIS, MO - Destination: 1H0, ST LOUIS, MO - Airport: MU89, Woodland Airstrip, runway 27, 1,750 × 80 ft, grass/turf - Equipment: Electronic primary flight display, Electronic multifunction display, ADS-B, Satellite tracking device, Handheld GPS, Onboard weather ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 75; injuries: serious; private; airplane ratings: single-engine land; medical: class 3, with waivers/limitations; seat: left; restraint: 4-point ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 41 °F, dew point 19 °F - Altimeter: 30.39 inHg - Observed at: KFYG, 20 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 (OpenAirDocs). - [Accident 20180208002119A](https://openairdocs.org/incident/20180208002119A), Feb 8, 2018: Henderson THORP T-18, Troy, MO, Destroyed. N600HH was traveling from east to west to land. The aircraft made contact with trees resulting in the accident. Trees were damaged approximately 20 feet in the… ## Docket (1 files) The files NTSB released with the investigation on March 28, 2018, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=96720. 1.7 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 1.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40461355&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF 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.