# NTSB CEN22LA123: Pitts S-1T, N731FL, Spring, TX, February 17, 2022 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Class 3 · Limited · Final report - Date: February 17, 2022, 14:48 local (20:48 UTC) - Place: Spring, TX · Final Runway 35L - Coordinates: 30.053099, -95.551847 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=30.0531&lon=-95.5518&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Defining event: [Initial climb: Powerplant sys/comp malf/fail](https://openairdocs.org/ntsb-events/340) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Central Region - Parties: Flight Standards District Office - NTSB case key (mKey): 104664 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN22LA123 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/104664/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=104664 - Page: https://openairdocs.org/ntsb/CEN22LA123 ## Probable cause The failure of maintenance personnel to properly connect the throttle cable, which led to the pilot’s inability to control engine power during the initial climb. Contributing to the accident was the pilot’s misjudgment of the headwind during the forced landing, which resulted in the airplane’s touchdown short of the runway and its impact with airport structures. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine controls: power lever](https://openairdocs.org/ntsb-findings/01057603): Aircraft › Aircraft power plant · Incorrect service/maintenance (probable cause); cases with it: [Pitts S-1T, 1 case](https://openairdocs.org/ntsb-findings/01057603/cases.md?model=7220404), [All aircraft, 95 cases](https://openairdocs.org/ntsb-findings/01057603/cases.md) - [Planning/preparation: flight planning/navigation](https://openairdocs.org/ntsb-findings/02061025): Personnel issues › Task performance · Pilot; cases with it: [Pitts S-1T, 1 case](https://openairdocs.org/ntsb-findings/02061025/cases.md?model=7220404), [All aircraft, 179 cases](https://openairdocs.org/ntsb-findings/02061025/cases.md) - [Wind: high wind](https://openairdocs.org/ntsb-findings/03034055): Environmental issues › Conditions/weather/phenomena · Decision related to condition; cases with it: [Pitts S-1T, 1 case](https://openairdocs.org/ntsb-findings/03034055/cases.md?model=7220404), [All aircraft, 112 cases](https://openairdocs.org/ntsb-findings/03034055/cases.md) - [Maintenance](https://openairdocs.org/ntsb-findings/02062000): Personnel issues › Task performance · Maintenance personnel (probable cause); cases with it: [Pitts S-1T, 1 case](https://openairdocs.org/ntsb-findings/02062000/cases.md?model=7220404), [All aircraft, 143 cases](https://openairdocs.org/ntsb-findings/02062000/cases.md) - [Performance/control parameters: descent/approach/glide path](https://openairdocs.org/ntsb-findings/01062040): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Pitts S-1T, 1 case](https://openairdocs.org/ntsb-findings/01062040/cases.md?model=7220404), [All aircraft, 809 cases](https://openairdocs.org/ntsb-findings/01062040/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Initial climb: Powerplant sys/comp malf/fail](https://openairdocs.org/ntsb-events/340) (defining event); cases with it: [Pitts S-1T, 1 case](https://openairdocs.org/ntsb-events/340/sequence.md?model=7220404), [All aircraft, 820 cases](https://openairdocs.org/ntsb-events/340/sequence.md) - [Landing: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Pitts S-1T, 1 case](https://openairdocs.org/ntsb-events/440/sequence.md?model=7220404), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) ## Analysis The pilot reported that, during the initial climbout, the engine did not respond to his throttle movements. The pilot turned the airplane back toward the airport and entered the downwind leg. While on the base leg, the pilot turned off the engine ignition switch and performed a forced landing. Due to a higher-than-anticipated headwind, the pilot misjudged the flight profile, and the airplane touched down short of the runway and impacted instrument landing system structures, which damaged both wings, the fuselage, and the empennage. Postaccident examination revealed the throttle cable was disconnected from the throttle lever arm at the fuel injector/control. A loose washer was found at the bottom of the engine cowling, and the castellated nut and cotter pin required for proper installation of the throttle linkage were not located. During the last annual inspection, the throttle cable had been disconnected to perform maintenance actions. The linkage hardware was likely not secured properly after that maintenance was performed, which resulted in the separation and subsequently the engine did not to respond to the pilot’s inputs during initial climb. ## Factual narrative On February 17, 2022, about 1448 central standard time, a Pitt S-1T, N731FL, was substantially damaged when it was involved in an accident at David Wayne Hooks Memorial Airport (DWH), Spring, Texas. The pilot was seriously injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot reported that, after departure from DWH, he noticed that engine power was not responding to throttle movements. The pilot turned back toward DWH and entered a left downwind leg to runway 35L. During the base turn and after turning off the engine ignition switch, the pilot executed a forced landing. Due to a higher-than-anticipated headwind, the pilot misjudged the flight profile, and the airplane landed before reaching runway 35L. The airplane impacted instrument landing system structures, which substantially damaged both wings, the fuselage, and the empennage. Postaccident examination revealed that the throttle cable was disconnected from the throttle lever arm at the fuel injector/control, and a loose washer was found at the bottom of the engine cowling. Proper installation of the throttle lever included a bolt, two washers, a castellated nut, and a cotter pin. The bolt, castellated nut, and cotter pin were not located. During the airplane’s last annual inspection, the engine fuel nozzles, fuel injector, and flow divider were removed for overhaul and were then reinstalled. During this maintenance, the throttle cable would have been disconnected, and it should have been reconnected once the maintenance was completed. After the annual inspection, no maintenance actions were recorded or reported that would have required the throttle cable to be disconnected. ## Aircraft - Registration: [N731FL](https://openairdocs.org/aircraft/N731FL), registered now, S/N 1061, built 2007 (OpenAirDocs) - Reported make and model: PITTS S-1T - Registry model: [Pitts S-1T](https://openairdocs.org/model/pitts-s-1t) (registry code 7220404) (OpenAirDocs) - Registry engine: [Lycoming AEIO-360-A1E](https://openairdocs.org/engine/lycoming-aeio-360-a1e) (registry code 41851, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 1061 - Year built: 2007 - Airframe hours: 1000 - Engines: Lycoming AEIO-360-A1E 200 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, April 28, 2021, 70 hours before - Departed: DWH, Houston, TX - Destination: DWH, Houston, TX - Airport: DWH, David Wayne Hooks Meml, runway 35L, 7,009 × 100 ft, asphalt - Equipment: ADS-B, Handheld GPS ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 67; injuries: serious; commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, with waivers/limitations; last flight review May 6, 2021; seat: single; restraint: 5-point; flight hours: 3,328 total, 1,900 in this make and model, 3,257 as pilot in command, 18 in the last 90 days, 7 in the last 30 days, 0 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 310° at 8 knots, gusting 15 - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 81 °F, dew point 48 °F - Altimeter: 29.90 inHg - Observed at: KDWH, 1 nm away - METAR: KDWH 171953Z 31008G15KT 10SM CLR 27/09 A2990 RMK AO2 SLP122 T02670089 ## 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 20220217002069A](https://openairdocs.org/incident/20220217002069A), Feb 17, 2022: Pitts S-1T, Spring, TX, Substantial damage. On 2/17/2022 at 1401 CST, a Pitts model S-1T, s/n 1061, N731FL, departed runway 35R at david wayne hooks airport (kdwh), when the aircraft encountered an… ## Docket (5 files) The files NTSB released with the investigation on June 14, 2023, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=104664. 7.9 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 9 pages, 1.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=14136603&FileExtension=pdf&FileName=6120%20-_Redacted-Rel.pdf - Photos (item 2, PDF, 3 pages, 948 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=14136501&FileExtension=pdf&FileName=Photos-Rel.pdf - Engine installation catalog (item 3, PDF, 3 pages, 171 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=14137131&FileExtension=pdf&FileName=Engine%20Installation%20Catalog-Rel.pdf - Engine maintenance log (item 4, PDF, 3 pages, 5.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=14137103&FileExtension=pdf&FileName=engine%20log_Redacted-Rel.pdf - FAA inspector report - excerpt (item 5, PDF, 1 page, 104 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=14136408&FileExtension=pdf&FileName=FAA%20Inspector%20Report%20-%20Excerpt-Rel.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.