# NTSB ERA25LA011: Saint Glasair II SFT, N952W, Forest, VA, October 11, 2024 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 3 · Limited · Final report - Date: October 11, 2024, 16:47 local (20:47 UTC) - Place: Forest, VA - Coordinates: 37.2781, -79.3885 - Nearby events: https://openairdocs.org/map.md?lat=37.2781&lon=-79.3885&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Defining event: [Approach-VFR pattern crosswind: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Eastern Region Aviation - Parties: FAA/FSDO - NTSB case key (mKey): 195308 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA25LA011 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/195308/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=195308 - Page: https://openairdocs.org/ntsb/ERA25LA011 ## Probable cause The installation of a non-failsafe coupler that resulted in the separation of the throttle cable from the throttle arm and a subsequent partial loss of engine power. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine fuel and control: fuel controlling system](https://openairdocs.org/ntsb-findings/01057320): Aircraft › Aircraft power plant · Design (probable cause); cases with it: [All aircraft, 59 cases](https://openairdocs.org/ntsb-findings/01057320/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 crosswind: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) (defining event); cases with it: [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Emergency descent: Landing area overshoot](https://openairdocs.org/ntsb-events/380); cases with it: [All aircraft, 400 cases](https://openairdocs.org/ntsb-events/380/sequence.md) - [Landing: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis During initial climb on a crosswind leg of the airport traffic pattern, the experimental amateur-built airplane exhibited a partial loss of engine power. The pilot attempted to glide the airplane to an upwind landing, but overshot the runway and landed in a field, resulting in substantial damage. Postaccident examination of the wreckage revealed that a threaded coupler between the throttle rod end and throttle cable had loosened and disconnected the cable from the throttle arm. This allowed the arm to move toward idle position. Use of a throttle cable coupler was likely a custom installation, and was not provided by the kit manufacturer. The installation provided a means to adjust the throttle cable; however, it also proved to be a single point of failure as there was no means to secure the coupler, such as a cotter pin or safety wire. ## Factual narrative On October 11, 2024, about 1647 eastern daylight time, an experimental amateur-built Glasair II SFT, N952W, was substantially damaged when it was involved in an accident near Forest, Virginia. The private pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot reported that he departed on a cross-country flight with 46 gallons of fuel. About 45 minutes later, upon nearing the destination airport, he entered the traffic pattern to land on runway 18. The pilot reported he had to make a left turn to avoid other inbound traffic, and he ended up circling the airport and reentering the traffic pattern on crosswind. The airplane was high during the landing approach and the pilot performed a go-around. While on the crosswind leg of the traffic pattern for a second approach, the airplane exhibited a partial loss of engine power. The pilot attempted to glide to runway 36 but overshot the runway and landed in a field. The airplane’s nose landing gear collapsed, resulting in substantial damage to the left wing and forward fuselage. Examination of the wreckage by an FAA inspector revealed that a threaded coupler between the throttle rod end and throttle cable had loosened and disconnected the cable from the throttle arm, which would allow the arm to freely move toward idle position. The inspector added that he had never seen such a coupler before on certificated aircraft. Although it provided a means to adjust the throttle cable, it also proved to be a single point of failure. Additionally, there was no means to secure the coupler, such as a cotter pin or safety wire. The inspector further stated that the airplane had accrued about 50 hours of operation since its most recent condition inspection was completed on February 1, 2024. According to the owner of the kit manufacturer, the make and model kit does not include throttle cables, and builders usually source engine controls from other companies. The owner added that he had never seen a throttle cable coupler used for aircraft. He believed it must have been a custom installation. ## Aircraft - Registration: N952W (not matched to a registry record) - Reported make and model: Saint Glasair II SFT - Category: Airplane, amateur-built - Serial number: 2117 - Year built: 1997 - Airframe hours: 2111 - Engines: Lycoming IO-360-A1B6D 200 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, February 1, 2024 - Departed: OMH, Orange, VA - Destination: Same as departure - Airport: W90, New London Airport, runway 36, 3,164 × 40 ft, asphalt - Equipment: Electronic flight bag or handheld device, Electronic primary flight display, ADS-B, Angle of attack indicator, Auto-pilot ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 65; injuries: none; private; airplane ratings: single-engine land; medical: class 3, without waivers/limitations; last flight review September 16, 2023; seat: left; restraint: 4-point; flight hours: 415 total, 65 in this make and model, 275 as pilot in command, 22 in the last 90 days, 13 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 210° at 5 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 70 °F, dew point 41 °F - Altimeter: 30.14 inHg - Observed at: LYH, 7 nm away - METAR: KLYH 112054Z 21005KT 10SM CLR 21/05 A3014 ## 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 20241011016139A](https://openairdocs.org/incident/20241011016139A), Oct 11, 2024: Saint Donald W GLASAIR II SFT, Bedford, VA, Substantial damage. Upon landing, pilot decided to go around, on climbout pilot felt the loss of thrust. Immediately turned back toward the runway and attempted to land. Pilot put… ## Docket (3 files) The files NTSB released with the investigation on April 2, 2025, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=195308. 1.6 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 10 pages, 933 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=17853136&FileExtension=pdf&FileName=6120%20Completed_Redacted-Rel.pdf - Memoranda for the record (item 2, PDF, 2 pages, 75 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=17851522&FileExtension=pdf&FileName=MFRs-Rel.pdf - Investigation photographs (item 3, PDF, 6 pages, 5 photos, 621 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=17853064&FileExtension=pdf&FileName=Investigation%20Photographs-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.