# NTSB WPR12LA437: Mccleery Rans S6ES, N623LB, Elverta, CA, September 25, 2012

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: September 25, 2012, 09:15 local (16:15 UTC)
- Place: Elverta, CA
- Coordinates: 38.281112, -121.483329 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=38.2811&lon=-121.4833&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Defining event: [Initial climb: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report January 12, 2015
- Report: Approved by Office Director
- NTSB office: Western Pacific Region
- Parties: FAA FSDO
- NTSB case key (mKey): 85145
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR12LA437
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/85145/pdf
- NTSB docket: https://data.ntsb.gov/Docket?ProjectID=85145
- Page: https://openairdocs.org/ntsb/WPR12LA437

## Probable cause

A loss of engine power during initial climb due to a failed piston ring.

## Findings

NTSB's coded findings; those marked are part of the probable cause.

- [Engine (reciprocating): recip eng cyl section](https://openairdocs.org/ntsb-findings/01058530): Aircraft › Aircraft power plant · Failure (probable cause); cases with it: [Mccleery Gregg A RANS S6ES, 1 case](https://openairdocs.org/ntsb-findings/01058530/cases.md?model=05901KQ), [All aircraft, 373 cases](https://openairdocs.org/ntsb-findings/01058530/cases.md)
- [Terrain: rough terrain](https://openairdocs.org/ntsb-findings/03021015): Environmental issues › Physical environment · Effect on operation; cases with it: [Mccleery Gregg A RANS S6ES, 1 case](https://openairdocs.org/ntsb-findings/03021015/cases.md?model=05901KQ), [All aircraft, 442 cases](https://openairdocs.org/ntsb-findings/03021015/cases.md)

## Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event best describes what happened.

- [Initial climb: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) (defining event); cases with it: [Mccleery Gregg A RANS S6ES, 1 case](https://openairdocs.org/ntsb-events/341/sequence.md?model=05901KQ), [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: [Mccleery Gregg A RANS S6ES, 1 case](https://openairdocs.org/ntsb-events/440/sequence.md?model=05901KQ), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md)
- [Landing: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Mccleery Gregg A RANS S6ES, 1 case](https://openairdocs.org/ntsb-events/470/sequence.md?model=05901KQ), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md)

## Analysis

The student pilot reported that, shortly after takeoff for his practical test for a sport pilot certificate, when the airplane was about 100 ft above ground level, the engine lost power. He then began an emergency descent to a nearby field. During the landing, the airplane collided with a dirt berm and subsequently nosed over. Postaccident examination of the engine revealed damage to both the forward and aft cylinder assemblies. The aft cylinder assembly's top piston ring was missing, and damage was noted to the associated ring land groove and piston. The lower piston ring was in place; however, the piston ring was distorted and jammed in its corresponding ring land groove. Mechanical-type damage was noted on the internal cylinder domes and piston faces of both the forward and aft cylinder assemblies, and the damage was consistent with pieces of the broken piston ring contacting the cylinder domes. The reason for the piston ring failure could not be determined. Postaccident review of the airplane's maintenance records revealed multiple entries outlining repairs to both the forward and aft cylinder assemblies; most of the repairs were associated with piston ring anomalies. One maintenance log entry indicated that the both the forward and aft cylinder assemblies' piston rings were replaced and that the cylinders were resurfaced due to "overheat damage."

## Factual narrative

On September 25, 2012, about 0915 Pacific daylight time, an experimental McCleery-Rans S6ES airplane, N623LB sustained substantial damage following a loss of engine power and subsequent forced landing near Elverta, California. The student pilot and Designated Pilot Examiner (DPE) conducting the check ride were not injured. The airplane was registered to the pilot, and operated as a visual flight rules (VFR) practical test exam flight under the provisions of 14 Code of Federal Regulations (CFR) Part 91. Visual meteorological conditions prevailed and no flight plan was filed for the local flight that originated from Elverta shortly before the accident.The accident occurred during the student pilot's practical test for a Sport Pilot certificate. The student pilot reported that he demonstrated a soft-field takeoff with 2 notches of flaps; as the airplane accelerated in ground effect to approximately 55 mph he transitioned to a climb. As the airplane climbed, about 100 feet above ground level (agl), the engine lost power and the pilot began an emergency descent to a nearby open field. He reported that the airplane touched down on the main wheels with the nose wheel off the ground; however, during the rollout in the open field the airplane collided with a dirt berm and subsequently nosed over. The airplane sustained substantial damage to the wing lift struts and fuselage. The experimental two-place high wing airplane was equipped with a Rotax 582 two-stroke, two-cylinder reciprocating engine rated at 65 horsepower. Postaccident airframe and engine examination by representatives from the Federal Aviation Administration and Rotax revealed the following findings: Aft (MAG) Piston and Cylinder Assembly The MAG piston was in place in the cylinder and remained attached to its associated connecting rod. The top MAG piston ring was missing and damage was noted to the associated ring land groove and piston. The lower piston ring was in place; however, the piston ring was distorted and jammed in its corresponding ring land groove. Mechanical type damage was noted to the internal cylinder dome of the cylinder head. The damage was consistent with pieces of the broken piston ring contacting the cylinder dome. Forward (PTO) Piston and Cylinder Assembly The PTO piston was in place in the cylinder and remained attached to its associated connecting rod. Both the upper and lower piston rings were in place and seated in their respective ring land grooves. Mechanical type damage was noted to the internal cylinder dome and piston face. The damage was consistent with pieces of the broken piston ring contacting the cylinder dome and piston face. Postaccident review of the airplane's maintenance records showed multiple entries that outlined repairs to both the MAG and PTO cylinder assemblies. In 2010 (specific date not legible) at 401 hours total time since new (TTSN) the MAG piston and ring assembly were replaced due to a cracked ring. An entry dated September 4, 2011 (at530 hours TTSN) indicated that the "top end" was reconditioned and new "rings" were installed. An entry dated November 05, 2011 (542 hours TTSN) indicted that the PTO and MAG rings were replaced and the cylinders were resurfaced due to "overheat damage."

## Aircraft

- Registration: [N623LB](https://openairdocs.org/deregistered/N623LB-2020-04-03), registration cancelled 2020-04-03, S/N 07011418ES, built 2006 (OpenAirDocs)
- Reported make and model: MCCLEERY RANS S6ES
- Registry model: [Mccleery Gregg A RANS S6ES](https://openairdocs.org/model/mccleery-gregg-a-rans-s6es) (registry code 05901KQ) (OpenAirDocs)
- Registry engine: [Rotax 582SER](https://openairdocs.org/engine/rotax-582ser) (registry code 55556, 2 cycle) (OpenAirDocs)
- Category: Airplane
- Serial number: 07011418ES
- Airframe hours: 594
- Engines: ROTAX 582 65 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Gallagher John P
- Registered owner: Gallagher John P
- Airworthiness certificate: Special, Experimental light sport (Special)
- Last inspection: Annual, October 5, 2011, 52 hours before
- Departed: NA, Elverta, CA
- Destination: NA, Elverta, CA

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 56; injuries: none; student; airplane ratings: single-engine land; medical: sport pilot; last flight review September 5, 2012; seat: left; flight hours: 155 total, 96 in this make and model, 123 as pilot in command, 30 in the last 90 days, 13 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 50 statute miles
- Lowest ceiling: none
- Temperature: 70 °F

## 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 20120925020919A](https://openairdocs.org/incident/20120925020919A), Sep 25, 2012: Mccleery Gregg A RANS S6ES, Elverta, CA, Substantial damage. The engine run-up was normal. Then seconds after the aircraft was maneuvering to establish a normal climb the engine shut down in flight. The loose of power…

## Docket (5 files)

The files NTSB released with the investigation on November 20, 2014, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=85145. 5.3 MB in all.

- Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 4.4 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40419227&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF
- Memo - Summary of Engine Exam (item 2, .PDF, 64 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40419228&FileExtension=.PDF&FileName=Memo%20-%20Summary%20of%20Engine%20Exam-Master.PDF
- Maintenance Records (item 3, .PDF, 569 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40419229&FileExtension=.PDF&FileName=Maintenance%20Records-Redacted.PDF
- Release of Aircraft Wreckage, NTSB Form 6120.15 (item 4, .PDF, 207 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40419230&FileExtension=.PDF&FileName=Release%20of%20Aircraft%20Wreckage,%20NTSB%20Form%206120.15-Redacted.PDF
- Evidence Control Form (item 5, .PDF, 74 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40419232&FileExtension=.PDF&FileName=Evidence%20Control%20Form-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.

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