# NTSB CEN11CA065: Welch Thomas RV9, N475TW, Sac City, IA, November 3, 2010 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: November 3, 2010, 17:00 local (22:00 UTC) - Place: Sac City, IA - Coordinates: 42.379165, -94.979721 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=42.3792&lon=-94.9797&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing-flare/touchdown: Loss of control in flight](https://openairdocs.org/ntsb-events/240) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report April 12, 2011 - Report: Approved by Office Director - NTSB office: Central Region - Parties: FAA-DSM-FSDO - NTSB case key (mKey): 77773 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN11CA065 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/77773/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=77773 - Page: https://openairdocs.org/ntsb/CEN11CA065 ## Probable cause The pilot's loss of directional control while landing with a gusting wind. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Turbulence](https://openairdocs.org/ntsb-findings/03032000): Environmental issues › Conditions/weather/phenomena · Effect on operation; cases with it: [Welch Thomas RV9, 1 case](https://openairdocs.org/ntsb-findings/03032000/cases.md?model=05617WD), [All aircraft, 92 cases](https://openairdocs.org/ntsb-findings/03032000/cases.md) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Welch Thomas RV9, 1 case](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=05617WD), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Performance/control parameters: directional control](https://openairdocs.org/ntsb-findings/01062020): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Welch Thomas RV9, 1 case](https://openairdocs.org/ntsb-findings/01062020/cases.md?model=05617WD), [All aircraft, 3,958 cases](https://openairdocs.org/ntsb-findings/01062020/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing-flare/touchdown: Loss of control in flight](https://openairdocs.org/ntsb-events/240) (defining event); cases with it: [Welch Thomas RV9, 1 case](https://openairdocs.org/ntsb-events/240/sequence.md?model=05617WD), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) - [Landing-flare/touchdown: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Welch Thomas RV9, 1 case](https://openairdocs.org/ntsb-events/470/sequence.md?model=05617WD), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis According to the pilot, the weather information he obtained en route indicated that the wind at his destination airport was from 300 degrees at 25 knots. The airplane encountered turbulence and wind gusts while on final approach and, despite the pilot’s control inputs, the airplane impacted terrain off the right side of the runway. The wind reported 25 miles from the accident site, about 15 minutes after the accident, was from 310 degrees at 23 knots gusting to 33 knots. The wings, firewall, and fuselage sustained substantial damage. ## Factual narrative The pilot obtained the weather information from Flight Watch during the flight. The pilot reported the local winds at his destination airport were from 300 degrees at 25 knots, so he elected to land on runway 32. The airplane encountered turbulence on final approach and at an altitude of 20 feet above the runway, the airplane unexpectedly began to gain altitude. The pilot pushed the control stick forward, but the airplane continued to gain altitude. The pilot reported that at 50 feet above the runway, he encountered turbulence and the nose of the airplane dropped abruptly. He added power and pulled back on the control stick, but the airplane impacted the terrain about 10 feet off the right side of the runway, coming to rest about 40 - 50 feet from the point of impact. The winds reported 25 miles from the accident site, about 15 minutes after the time of the accident, were from 310 degrees at 23 knots gusting to 33 knots. The wings, firewall, and fuselage sustained substantial damage. ## Aircraft - Registration: [N475TW](https://openairdocs.org/deregistered/N475TW-2014-10-27), registration cancelled 2014-10-27, S/N 90475, built 2001 (OpenAirDocs) - Reported make and model: WELCH THOMAS RV9 - Registry model: [Welch Thomas RV9](https://openairdocs.org/model/welch-thomas-rv9) (registry code 05617WD) (OpenAirDocs) - Registry engine: [Amateur-built UNKNOWN ENG](https://openairdocs.org/engine/amateur-built-unknown-eng) (registry code 99999) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 90475 - Airframe hours: 446 - Engines: NSI EJ25 180 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Micheal L. Harmon, Jr. - Registered owner: Micheal L. Harmon, Jr. - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, April 7, 2010, 85 hours before - Departed: 1H2, Effingham, IL - Destination: SKI, Sac City, IA - Airport: SKI, Sac City Municipal, runway 32, 2,350 × 60 ft, concrete ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 35; injuries: none; private; airplane ratings: single-engine land; medical: class 3, without waivers/limitations; last flight review June 5, 2010; seat: left; flight hours: 305 total, 90 in this make and model, 240 as pilot in command, 70 in the last 90 days, 28 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 310° at 23 knots, gusting 33 - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 59 °F, dew point 9 °F - Altimeter: 30.09 inHg - Observed at: CIN, 25 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 20101103052879A](https://openairdocs.org/incident/20101103052879A), Nov 3, 2010: Welch Thoma RV9, Sac City, IA, Substantial damage. Pilot failed to maintain control of the aircraft while performing a landing in gusting conditions. The pilot, who was the only occupant, was not injured. This… ## Other investigations on N475TW (1) 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 SEA08CA010](https://openairdocs.org/ntsb/SEA08CA010), Oct 14, 2007: Welch RV-9 (N475TW), Bigfork, MT, substantial damage. Probable cause: Fuel starvation while on downwind for landing. The pilot's inadequate in-flight fuel management planning was a factor. ## Docket (1 files) The files NTSB released with the investigation on December 10, 2010, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=77773. 1.1 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 1.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40340536&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.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.