# NTSB WPR18LA250: Stoddard Hamilton Glasair Super IIS, N8162H, Yuma, AZ, August 27, 2018 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: August 27, 2018, 10:36 local (17:36 UTC) - Place: Yuma, AZ - Coordinates: 32.669998, -114.59333 - Nearby events: https://openairdocs.org/map.md?lat=32.6700&lon=-114.5933&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-cruise: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report November 19, 2019 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Superior Air Parts, Federal Aviation Administration FSDO - NTSB case key (mKey): 98220 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR18LA250 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/98220/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=98220 - Page: https://openairdocs.org/ntsb/WPR18LA250 ## Probable cause A total loss of engine power as a result of the detachment of the throttle linkage from the throttle arm of the fuel injector servo due to an insufficiently tightened and secured bolt and the subsequent inadequate maintenance inspection. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine fuel and control: fuel control/carburetor](https://openairdocs.org/ntsb-findings/01057322): Aircraft › Aircraft power plant · Incorrect service/maintenance (probable cause); cases with it: [Hyneman Michael GLASAIR-SUPER-2SRG, 1 case](https://openairdocs.org/ntsb-findings/01057322/cases.md?model=05628VG), [All aircraft, 195 cases](https://openairdocs.org/ntsb-findings/01057322/cases.md) - [Engine fuel and control: fuel control/carburetor](https://openairdocs.org/ntsb-findings/01057322): Aircraft › Aircraft power plant · Inadequate inspection (probable cause); cases with it: [Hyneman Michael GLASAIR-SUPER-2SRG, 1 case](https://openairdocs.org/ntsb-findings/01057322/cases.md?model=05628VG), [All aircraft, 195 cases](https://openairdocs.org/ntsb-findings/01057322/cases.md) - [Maintenance: installation](https://openairdocs.org/ntsb-findings/02062035): Personnel issues › Task performance · Maintenance personnel (probable cause); cases with it: [Hyneman Michael GLASAIR-SUPER-2SRG, 1 case](https://openairdocs.org/ntsb-findings/02062035/cases.md?model=05628VG), [All aircraft, 371 cases](https://openairdocs.org/ntsb-findings/02062035/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-cruise: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) (defining event); cases with it: [Hyneman Michael GLASAIR-SUPER-2SRG, 1 case](https://openairdocs.org/ntsb-events/342/sequence.md?model=05628VG), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Emergency descent: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341); cases with it: [Hyneman Michael GLASAIR-SUPER-2SRG, 1 case](https://openairdocs.org/ntsb-events/341/sequence.md?model=05628VG), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Emergency descent: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Hyneman Michael GLASAIR-SUPER-2SRG, 1 case](https://openairdocs.org/ntsb-events/440/sequence.md?model=05628VG), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Emergency descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Hyneman Michael GLASAIR-SUPER-2SRG, 1 case](https://openairdocs.org/ntsb-events/470/sequence.md?model=05628VG), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The private pilot reported that, about 35 minutes into the personal cross-country flight, the experimental, amateur-built airplane's alternator field toggle switch/circuit breaker tripped. He reset the switch, and all systems appeared normal. About 5 minutes later, the switch tripped again, and the pilot cycled the switch. About 2 minutes later, the pilot noticed that the engine manifold pressure was dropping, along with the airplane's airspeed, consistent with a partial loss of engine power. The engine then experienced a total loss of power when he was maneuvering for an emergency landing to a nearby airport. The airplane subsequently landed short of the runway and sustained substantial damage to the aft fuselage. The engine had been installed about 91 flight hours and 5 months before the accident flight, and a condition inspection was completed the same month of installation. Maintenance records indicated that during the period between the engine installation and the accident, maintenance was limited to routine oil changes, magneto timing adjustments, the replacement of exhaust gas temperature and cylinder head temperature probes, and the installation of a replacement alternator. Postaccident examination of the engine revealed that the throttle linkage had detached from the throttle arm of the fuel injection servo. The rod end bearing for the linkage and the throttle arm were intact and undamaged, but the connecting bolt and its associated washers, castellated nut, and cotter pin were missing. The butterfly valve within the throttle body was in the closed position, and the throttle lever in the cabin was in the full forward (open) position. It is likely that the bolt securing the linkage had not been sufficiently tightened and secured with a cotter pin during the installation and that the error was not detected during the subsequent condition inspection. The investigation determined that the electrical system malfunction was unrelated to the loss of engine power. ## Factual narrative On August 27, 2018, at 1036 mountain standard time, an experimental amateur-built Stoddard Hamilton Glasair Super IIS RG airplane, N8162H, lost engine power and landed in a parking lot just short of Yuma Marine Corps Air Station/Yuma International Airport (NYL), Yuma, Arizona. The private pilot was not injured, and the airplane sustained substantial damage to the aft fuselage during the forced landing. The airplane was registered to Rich Airplanes LLC., and operated by the pilot under the provisions of Title 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed, and no flight plan had been filed. The cross-country flight originated from Montgomery-Gibbs Executive Airport, San Diego, California, at 0942 Pacific daylight time and destined for Marana Regional Airport, Marana, Arizona. The pilot stated that he completed a preflight inspection prior to departure, and the airplane performed appropriately during the runup. The departure and climb were uneventful, and after reaching 9,500 ft mean sea level, he configured the airplane for cruise. About 35 minutes later the airplane's multifunction display indicated an "electrical problem, check voltage" alert. He noticed that the airplane's main battery was not charging, and that the alternator field toggle switch/circuit breaker had tripped off, but the alternator circuit breaker was still in. He reset the toggle switch, and the battery began to charge again, and all systems appeared normal. About 5 minutes later, the display indicated the same warning, and the toggle switch again tripped. He cycled the switch and the battery started to charge again. About 2 minutes later he noticed that the engine manifold pressure was beginning to drop along with the airplane's airspeed. He stated that the fuel flow, fuel pressure, and oil pressure appeared normal, and he could not discern an appreciable reduction in cylinder head or exhaust gas temperatures (CHT, EGT). He selected an alternate fuel tank, turned on the auxiliary electrical fuel pump, and adjusted the throttle, with no change, and by now the multifunction displayed indicated the engine was producing 30% of its rated power. The pilot declared an emergency with Yuma Radar Approach Control and was provided a local control frequency for NYL. He stated that the engine was still producing partial power when the local tower controller cleared him for an emergency landing on runway 17, and then changed the clearance to runway 21L, which was longer. The pilot stated that he was too high to land, so performed a 360° turn at the north end of the runway, but during the turn the engine lost all power, and the airplane landed short. The airplane's multifunction display system was a Dynon SkyView Touch, which was configured to record an array of airframe and engine parameters, including main bus voltage. Examination of the recorded data revealed a voltage drop from 14.3 to 12.9 volts at 1017 and 1021, consistent withthe pilot's recollection. The drops lasted 20 and 30 seconds respectively, after which normal voltage and current draw was restored. All other engine parameters remained unchanged during the excursions. Forty seconds after the last voltage drop was restored, the manifold pressure decreased from 21 to 10 inches of mercury and the fuel flow from 10 to 4 gallons per hour (gph). A few seconds later the EGT and CHT's began to decrease. The manifold pressure and fuel flow remained steady for the next 9 minutes, following which they dropped to 7 inches of mercury and 0.7 gph respectively. The data ended about 3 minutes later. The airplane was equipped with a fuel-injected XP series IO-361-J1HD2 engine, manufactured by Superior Air Parts. The engine was installed new on April 1, 2018, and a condition inspection was completed on April 24, 2018 before the first flight with the engine. At the time of the accident, the engine had accumulated about 91 hours of flight time since installation. Maintenance records indicated that during the period between the engine installation and accident, maintenance events were limited to routine oil changes, magneto timing adjustments, replacement of EGT and CHT probes, and the installation of a replacement alternator. Postaccident examination of the engine revealed that the throttle linkage had detached from the throttle arm of the fuel injection servo. The rod end bearing (Heim joint) for the linkage, and the throttle arm were intact and undamaged, but the connecting bolt and its associated washers, castellated nut and cotter pin were not present (Photo 1). The butterfly valve within the throttle body was in the closed position, and the throttle lever in the cabin was in the full forward, "open" position. Photo 1 – Throttle Linkage ## Aircraft - Registration: [N8162H](https://openairdocs.org/aircraft/N8162H), registered now, S/N 2224, built 1995 (OpenAirDocs) - Reported make and model: Stoddard Hamilton GLASAIR SUPER IIS (RG) - Registry model: [Hyneman Michael GLASAIR-SUPER-2SRG](https://openairdocs.org/model/hyneman-michael-glasair-super-2srg) (registry code 05628VG) (OpenAirDocs) - Registry engine: [Lycoming I0360 series](https://openairdocs.org/engine/lycoming-i0360-series) (registry code 41515, reciprocating) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 2224 - Year built: 1995 - Airframe hours: 2020.5 - Engines: Superior Air Parts IO-361-J1HD2 200 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, April 24, 2018, 91 hours before - Departed: MYF, San Diego, CA - Destination: AVQ, Marana, AZ - Airport: NYL, Yuma Mcas/Yuma Intl, runway 21L, 9,240 × 150 ft, asphalt - Equipment: Angle of attack indicator, ADS-B, Satellite tracking device, Onboard weather, Handheld GPS, Electronic primary flight display, Electronic multifunction display, Auto-pilot ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 63; injuries: none; private; airplane ratings: single-engine land; medical: class 3, with waivers/limitations; last flight review October 2, 2017; seat: left; restraint: 4-point; flight hours: 1,598.4 total, 298.3 in this make and model, 1,598.4 as pilot in command, 74.4 in the last 90 days, 13.5 in the last 30 days, 0 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: variable at 4 knots - Visibility: 7 statute miles - Lowest ceiling: none - Temperature: 97 °F, dew point 57 °F - Altimeter: 29.80 inHg - Observed at: KNYL, 2 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 20180827024159A](https://openairdocs.org/incident/20180827024159A), Aug 27, 2018: Hyneman Michael GLASAIR-SUPER-2SRG, Yuma, AZ, Substantial damage. On 8-27-2018 while at cruise 9500AGL pilot encountered an alternator switch problem and ultimately lost power which caused him to land short of the Yuma… ## Docket (5 files) The files NTSB released with the investigation on December 6, 2018, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=98220. 11.6 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 2.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40468997&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Dynon "Sky View Touch" Multifunction Display Data (item 2, .CSV, 8.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469001&FileExtension=.csv&FileName=Dynon%20%22Sky%20View%20Touch%22%20Multifunction%20Display%20Data-Master.csv - Maintenance Logbook Excerpts (item 3, .PDF, 829 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469004&FileExtension=.PDF&FileName=Maintenance%20Logbook%20Excerpts-Master.PDF - Statement of Party Representatives to NTSB Investigation (item 4, .PDF, 96 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469006&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation-Master.PDF - Photographs (item 5, .PDF, 3 photos, 305 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469009&FileExtension=.PDF&FileName=Photographs-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.