# NTSB ERA18LA181: Beech 35B33, N9745Y, Berlin, MD, June 29, 2018 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Class 3 · Limited · Final report - Date: June 29, 2018, 09:15 local (13:15 UTC) - Place: Berlin, MD · Golf course - Coordinates: 38.311389, -75.129997 - Nearby events: https://openairdocs.org/map.md?lat=38.3114&lon=-75.1300&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: Serious injuries - Injuries: 1 serious, 1 minor - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Eastern Region Aviation - Parties: CMI, FAA/FSDO, Textron - NTSB case key (mKey): 97641 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA18LA181 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/97641/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=97641 - Page: https://openairdocs.org/ntsb/ERA18LA181 ## Probable cause The failure of the No. 3 cylinder exhaust valve, which resulted in the total loss of engine power during takeoff. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine (reciprocating): recip engine power section](https://openairdocs.org/ntsb-findings/01058520): Aircraft › Aircraft power plant · Failure (probable cause); cases with it: [Beech 35-B33, 2 cases](https://openairdocs.org/ntsb-findings/01058520/cases.md?model=1151406), [All aircraft, 233 cases](https://openairdocs.org/ntsb-findings/01058520/cases.md) - [Maintenance/inspections](https://openairdocs.org/ntsb-findings/01010500): Aircraft › Aircraft handling/service · Not serviced/maintained; cases with it: [Beech 35-B33, 1 case](https://openairdocs.org/ntsb-findings/01010500/cases.md?model=1151406), [All aircraft, 103 cases](https://openairdocs.org/ntsb-findings/01010500/cases.md) - [Inspection: scheduled/routine inspection](https://openairdocs.org/ntsb-findings/02061520): Personnel issues › Task performance · Maintenance personnel; cases with it: [Beech 35-B33, 1 case](https://openairdocs.org/ntsb-findings/02061520/cases.md?model=1151406), [All aircraft, 167 cases](https://openairdocs.org/ntsb-findings/02061520/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: [Beech 35-B33, 10 cases](https://openairdocs.org/ntsb-events/341/sequence.md?model=1151406), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Emergency descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Beech 35-B33, 6 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=1151406), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The pilot stated that, shortly after he retracted the landing gear during the initial climb after takeoff, the airplane began to vibrate and the engine lost power. The pilot initiated a 180° return to the runway, but unable to reach it, performed a forced landing to a golf course. Postaccident examination of the airplane’s engine revealed that the No. 3 cylinder sustained catastrophic damage, including heavy mechanical damage to the piston and separation of the exhaust valve, a portion of which was lodged under the intake valve. Numerous pieces of metal consistent with material from the No. 3 piston head were found in the oil sump. Given this information, it is likely that the loss of engine power was due to the failure of the No. 3 exhaust valve. The engine manufacturer's maintenance manual recommended that this engine be overhauled at 1,500 hours of operation or every 12 years, whichever occurred first. The maintenance manual also recommended that a borescope be used to inspect the engine’s cylinders during every 100-hour/annual inspection in conjunction with a compression test. The engine maintenance records listed the compression test results during previous annual inspections but did not indicate whether the cylinders had been inspected with a borescope. At the previous annual inspection, about 1 month before the accident, the engine total time was 1,769.1 hours. Additionally, the engine was manufactured about 37 years prior to the accident and had not been overhauled. The investigation did not determine if the impending failure of the exhaust valve could have been detected and corrected had the borescope inspections been performed and/or the engine had been overhauled. ## Factual narrative On June 29, 2018, about 0915 eastern daylight time, a Beech 35-B33, N9745Y, was substantially damaged when it was involved in an accident near Berlin, Maryland. The private pilot was seriously injured, and the passenger sustained minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot stated that the preflight inspection and the engine runup were normal. After takeoff, he retracted the landing gear, and the airplane began to vibrate. He checked his cockpit gauges, but the “plane was losing power and the vibration increased.” The pilot transmitted via radio that he was returning to the airport; however, unable to reach the runway, the pilot performed a forced landing on a golf course. After landing, a small postcrash engine compartment fire ensued. A Federal Aviation Administration (FAA) inspector examined the airplane where it came to rest about 1/3 mile west of the departure airport. The left wing displayed leading edge damage and was canted upward from midspan to the wingtip. The engine was partially separated from the airframe, and the landing gear and wing flaps were retracted. Further examination revealed fire damage to the aft section of the engine. The fuel selector valve was in the right tank position. The fuel selector valve screen was removed and inspected; no debris was found. The fuel line from the firewall to the fuel pump inlet was fracture-separated at the inlet fitting. The fuel line from the fuel pump to the fuel metering unit was intact, and the fuel line from the metering unit to the manifold valve was separated at the metering unit. All other B-nuts remained attached to their fittings. Flight control cable continuity was established from the control surfaces to the cockpit controls. Continuity of the crankshaft and camshaft were confirmed when the propeller was rotated by hand, and thumb compression was obtained on all cylinders except No. 3. Borescope examination of the No. 3 cylinder revealed catastrophic damage, including heavy mechanical damage to the piston and separation of the exhaust valve, a portion of which was lodged under the intake valve. The No. 3 pushrods did not display any visible damage or bending. Numerous pieces of metal consistent with material from the No. 3 piston head were found in the oil sump. No other engine anomalies were observed. The most recent annual inspection was completed on May 7, 2018, at a tachometer time of 1,162.5 hours and a recorded engine total time of 1,769.1 hours. Additionally, the engine was manufactured during March 1981 and had not been overhauled. The Continental Motors M-0 Maintenance Manual recommended that IO-470-K engines with serial numbers before 1006000, which included the accident engine, be overhauled at 1,500 hours or every 12 years, whichever occurred first. Additionally, the Maintenance Manual recommends a borescope inspection of the cylinders during every 100-hour/annual inspection in conjunction witha compression test. The engine maintenance records listed the compression test results during the annual inspections but did not indicate whether the borescope inspections were conducted. ## Aircraft - Registration: [N9745Y](https://openairdocs.org/deregistered/N9745Y-2020-01-31), registration cancelled 2020-01-31, S/N CD-681, built 1963 (OpenAirDocs) - Reported make and model: Beech 35B33 (NO SERIES) - Registry model: [Beech 35-B33](https://openairdocs.org/model/beech-35-b33) (registry code 1151406) (OpenAirDocs) - Registry engine: [Continental I0-470 series](https://openairdocs.org/engine/continental-i0-470-series) (registry code 17027, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: CD-681 - Year built: 1963 - Airframe hours: 3553.8 - Engines: Continental IO-470 225 horsepower reciprocating - Damage: Substantial damage - Fire: On-Ground - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, May 7, 2018 - Departed: OXB, Berlin, MD - Destination: PSK, Dublin, VA - Flight plan: IFR - Airport: OXB, Ocean City Muni - Equipment: Video recording device, ADS-B, Auto-pilot, Electronic flight bag or handheld device, Onboard weather ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 60; injuries: serious; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, with waivers/limitations; last flight review May 24, 2018; seat: left; flight hours: 1,191 total ## Weather - Conditions: Visual (VMC), Day - Wind: 60° at 8 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 82 °F, dew point 68 °F - Altimeter: 30.00 inHg - Observed at: OXB ## 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 20180629013029A](https://openairdocs.org/incident/20180629013029A), Jun 29, 2018: Beech 35-B33, Berlin, MD, Substantial damage. Pilot departed from oxb on rwy 32. On climb out the aircraft lost power. The pilot was unable to return to the airport and made a forced landing on golf course… ## Docket (8 files) The files NTSB released with the investigation on October 21, 2021, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=97641. 29.3 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 8.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11852704&FileExtension=pdf&FileName=NTSB%20Form%206120_Redacted-Rel.pdf - Onboard image recorder - specialist's factual report (item 2, PDF, 10 pages, 896 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8882303&FileExtension=pdf&FileName=era18la181%20onboard%20report-Rel.pdf - Pilot's statement (item 3, PDF, 1 page, 73 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11915630&FileExtension=pdf&FileName=Memorandum%20for%20Record%20-%20Mascelli-Rel.pdf - Maintenance records (item 4, PDF, 17 pages, 10.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11966642&FileExtension=pdf&FileName=Maintenance%20Records_Redacted-Rel.pdf - Maintenance manual excerpts (item 5, PDF, 11 pages, 770 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11943783&FileExtension=pdf&FileName=Pages%20from%20Continental%20Maintenance%20Manual-Rel.pdf - Photos (item 6, PDF, 4 pages, 2.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11943627&FileExtension=pdf&FileName=Photos-Rel.pdf - Party forms (item 7, PDF, 10 pages, 688 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11939725&FileExtension=pdf&FileName=Signed%20party%20forms_Redacted-Rel.pdf - NTSB airframe and engine examination summary (item 8, PDF, 12 pages, 5.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11943284&FileExtension=pdf&FileName=ERA18LA181%20Exam%20Notes-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.