# NTSB CEN23LA023: Stephen J Hoffman MS-500, N778MS, Houston, TX, October 29, 2022 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Class 4 · Limited · Final report - Date: October 29, 2022, 11:40 local (16:40 UTC) - Place: Houston, TX - Coordinates: 29.60559, -95.166497 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=29.6056&lon=-95.1665&mi=10 - Phase of flight: [Standing](https://openairdocs.org/ntsb-phases/150) (OpenAirDocs' grouping) - Defining event: [Standing-engine(s) start-up: Ground collision](https://openairdocs.org/ntsb-events/200) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed - Report: Approved by Office Director - Investigation class: Class 4 - Basic report with no Prelim publish - NTSB office: Central Region - Parties: FAA - NTSB case key (mKey): 106231 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN23LA023 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/106231/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=106231 - Page: https://openairdocs.org/ntsb/CEN23LA023 ## Probable cause The pilot’s failure to secure the magneto switch before attempting to hand rotate the engine which resulted in an inadvertent engine start, a runaway airplane, and subsequent impact with parked airplanes. Contributing to the accident was the failure to properly secure the airplane with chocks. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Planning/preparation](https://openairdocs.org/ntsb-findings/02061000): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Stephen J Hoffman MS-500, 1 case](https://openairdocs.org/ntsb-findings/02061000/cases.md?model=05634S6), [All aircraft, 113 cases](https://openairdocs.org/ntsb-findings/02061000/cases.md) - [Parking/securing](https://openairdocs.org/ntsb-findings/01011000): Aircraft › Aircraft handling/service · Incorrect use/operation (probable cause); cases with it: [Stephen J Hoffman MS-500, 1 case](https://openairdocs.org/ntsb-findings/01011000/cases.md?model=05634S6), [All aircraft, 11 cases](https://openairdocs.org/ntsb-findings/01011000/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Standing-engine(s) start-up: Ground collision](https://openairdocs.org/ntsb-events/200) (defining event); cases with it: [Stephen J Hoffman MS-500, 1 case](https://openairdocs.org/ntsb-events/200/sequence.md?model=05634S6), [All aircraft, 618 cases](https://openairdocs.org/ntsb-events/200/sequence.md) ## Analysis The pilot reported that he was preparing for a display flight in a local airshow which included a preflight procedure to rotate the engine prior to start for lubrication purposes. During the procedure, the electric starter motor struggled to rotate the engine due to viscous oil because of cooler overnight temperatures, and the main circuit breaker had tripped. The pilot turned off all cockpit switches, but forgot to turn off the magneto switch, and exited the airplane. The pilot then utilized a hand crank to rotate the engine, and the engine unexpectedly started. The wheel chocks had been previously removed in preparation for the planned flight, and the airplane began to move. Several ground personnel attempted to stop the airplane but were unsuccessful before the airplane impacted two parked airplanes. The airplane sustained substantial damage to both wings and the elevator. The pilot reported no preimpact mechanical malfunctions or failures with the airplane that would have precluded normal operation. ## Aircraft - Registration: [N778MS](https://openairdocs.org/aircraft/N778MS), registered now, S/N 4, built 2018 (OpenAirDocs) - Reported make and model: STEPHEN J HOFFMAN MS-500 - Registry model: [Stephen J Hoffman MS-500](https://openairdocs.org/model/stephen-j-hoffman-ms-500) (registry code 05634S6) (OpenAirDocs) - Registry engine: [Argus AS10-P](https://openairdocs.org/engine/argus-as10-p) (registry code 05406, reciprocating) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 4 - Year built: 2018 - Airframe hours: 69 - Engines: Argus Motoren AS-10C 240 horsepower reciprocating - Damage: Substantial damage - Flight: Air race/show, Part 91 - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, November 1, 2021 - Airport: EFD, Ellington - Equipment: ADS-B ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 66; injuries: minor; private; airplane ratings: single-engine land; medical: basicmed, without waivers/limitations; last flight review June 19, 2021; seat: none; restraint: 4-point; flight hours: 500 total, 57 in this make and model, 394 as pilot in command, 5 in the last 90 days, 4 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 250° at 9 knots - Visibility: 10 statute miles - Lowest ceiling: 2,600 ft broken - Temperature: 64 °F, dew point 54 °F - Altimeter: 30.03 inHg - Observed at: KEFD, 1 nm away - METAR: KEFD 291754Z 25009KT 10SM BKN026 18/12 A3003 ## 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 20221029019702A](https://openairdocs.org/incident/20221029019702A), Oct 29, 2022: Stephen J Hoffman MS-500, Houston, TX, Substantial damage. Iic statement: there were several eyewitnesses to the accident and this statement has excerpts from their observations and pilot statement. The pilot of… ## Docket (2 files) The files NTSB released with the investigation on November 30, 2022, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=106231. 3.5 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 2.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=14777222&FileExtension=pdf&FileName=6120_Redacted-Rel.pdf - Accident photographs (item 2, PDF, 2 pages, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=14778240&FileExtension=pdf&FileName=Photo%20Array-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.