Friday, August 5, 2016

Cessna 150L, N10770: Accident occurred August 04, 2016 near Brown County Airport (KGEO), Georgetown, Brown County, Ohio

Aviation Accident Final Report - National Transportation Safety Board: https://app.ntsb.gov/pdf

The National Transportation Safety Board did not travel to the scene of this accident.

Additional Participating Entity: 

Federal Aviation Administration / Flight Standards District Office; Columbus, Ohio

Investigation Docket - National Transportation Safety Board: https://dms.ntsb.gov/pubdms


Aviation Accident Factual Report - National Transportation Safety Board: https://app.ntsb.gov/pdf

FAA Flight Standards District Office: FAA Cincinnati FSDO-05

http://registry.faa.gov/N10770


NTSB Identification: CEN16LA306
14 CFR Part 91: General Aviation
Accident occurred Thursday, August 04, 2016 in Russellville, OH
Probable Cause Approval Date: 06/20/2017
Aircraft: CESSNA 150L, registration: N10770
Injuries: 1 Minor, 1 Uninjured.

NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.

As the private pilot was descending the airplane for landing, he heard a loud "bang," and the engine subsequently began running rough. Unable to maintain altitude, the pilot conducted a forced landing to a soybean field, during which the airplane impacted a ditch and nosed over. Examination of the engine revealed that the No. 2 cylinder was completely separated between the flange and the head. Examination of the cylinder revealed a fatigue crack that initiated at a cooling fin valley on the exterior surface. The fatigue crack grew around 40% of the circumference of the cylinder, and overstress led to the eventual cylinder fracture. A metallographic cross-section of the cylinder revealed corrosion pits under the paint and primer. The alloy is not necessarily susceptible to pitting, but crevice corrosion near an unpainted area or exposure to salt environments can lead to similar corrosion features.

The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
A partial loss of engine power due to a fatigue crack of the No. 2 cylinder cooling fin, which resulted in failure of the No. 2 cylinder. 

On August 4, 2016, at 2004 eastern daylight time, the pilot of a Cessna 150L, N10770, impacted terrain in a soybean field near Russellville, Ohio, after a loss of engine power. The private pilot on board sustained a minor injury and the pilot-rated passenger was not injured. The airplane was substantially damaged. The airplane was registered to and operated by a private individual under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed at the time of the accident, and no flight plan had been filed. The local flight originated from Brown County Airport (KGEO), Georgetown, Ohio, about 1945.

The pilots told an FAA inspector that while they were descending for landing, they heard a loud "bang" and the engine began running rough. Unable to maintain altitude, they made a forced landing in a soybean field. The airplane struck a ditch and nosed over. Examination of the engine revealed the number 2 cylinder had completely separated between the flange and the head.

The pilot was instructed to ship the cylinder halves to the National Transportation Safety Board's (NTSB) Materials Laboratory for examination. According to the Materials Laboratory's Factual Report (16-110), the cylinder had fractured about the circumference of the seventh cooling fin valley through approximately 40% of the cross section. The fracture was relatively flat, exhibited a reflective luster, and was oriented in the direction of piston movement. The fracture surface revealed the presence of crack arrest marks, which were consistent with progressive cracking due to fatigue. Additionally, several cooling fin flange surfaces exhibited small circular features consistent with pitting. An initial thumbnail crack was present adjacent to the crack initiation site, with radial marks and crack arrest marks propagating outward. Fatigue striations were present, consistent with fatigue crack propagation. The crack initiation site on the head side of the fracture surface consisted of three stepped features containing ratchet marks between the steps, consistent with multiple crack initiation sites that had coalesced as the fatigue cracks grew and propagated inward. The mating (open piston side) fracture surface exhibited three ridge shapes, consistent with the previously observed ratchet marks on the head side fracture surface.

According to the engine maintenance records, cylinder number 2 (serial number 0049), manufactured by Superior Air Parts, Coppell, Texas, was overhauled on April 14, 2000. The overhaul included grounding the intake and exhaust valve seats, grounding the intake valve, replacing the intake and exhaust guides, and replacing the exhaust valve. The cylinder was then pressure checked and returned to service.

NTSB Identification: CEN16LA306
14 CFR Part 91: General Aviation
Accident occurred Thursday, August 04, 2016 in Russellville, OH
Aircraft: CESSNA 150L, registration: N10770
Injuries: 2 Minor.

This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed. NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.

On August 4, 2016, at 2009 eastern daylight time, the pilot of a Cessna 150L, N10770, made a forced landing in a soybean field 4 miles easts-southeast of Russellville, Ohio, after the engine lost power. Of the two pilots on board, one sustained a minor injury and the other was not injured. The airplane was substantially damaged. The airplane was registered to and operated by a private individual under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed at the time of the accident, and no flight plan had been filed. The local flight originated from Brown County Airport (KGEO) , Georgetown, Ohio, about 1930.

The pilots told an FAA inspector as they were descending for landing, they heard a loud "bang" and the engine began running rough. Unable to maintain altitude, they made a forced landing in a soybean field, struck a ditch, and nosed over.

Examination of the engine revealed the number 2 cylinder had separated between the flange and the head.


Update, Friday, 6:30 a.m. : Two pilots whose planes crashed minutes apart Thursday night in Brown County reported engine problems prior to crashing, officials said in a news release.

A Cessna 150L  piloted by Timothy Howser, 46, of Batavia crashed into a field at 8:04 p.m. Howser was treated for non-life threatening injuries while passenger Tony Howser, 44, of Highland Heights, wasn't injured. The crash occurred near Fryer Road in Russellville, Ohio.

Kristopher Cooper, 42, of Harnersville, Ohio, wasn't injured when his experimental aircraft crashed about three minutes later near Carpenter Road in Mount Orab, Ohio.

Both planes refueled prior to their departure from the Brown County Airport, authorities said.

The Federal Aviation Administration was notified of the crashes, which are still being investigated.

Previous report: Two single-engine planes crashed in Brown County Thursday evening within 3 minutes of each other, according to Brown County Ohio State Highway Patrol.

The two incidents appear to be completely separate from one another, a dispatcher there said. One plane fell near Fryer Road and Clifton Avenue, and the other went down near Carpenter and Boyd roads at 8:04 p.m. and 8:07 p.m., respectively.

Perhaps even more surprising, there were no injuries.

Both planes landed in soybean fields and caused no damage – except for the planes. The crash sites are about a 25-minute drive apart from each other.

Officials are looking into the causes of both crashes, which are unknown at this time.

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