Pilot Debrief

Cessna 172RG near Ocean City, MD — 2019-07-16

Final reportANC19LA034
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Date
2019-07-16
Location
Ocean City, MD, USA
Aircraft
Cessna 172RG
Registration
N9715B
Category
Airplane
Highest injury
None
Fatalities
0
Phase of flight
Cruise

Probable cause

A partial loss of power due to the liberation or failure of the No. 2 cylinder's exhaust valve.

NTSB narrative

According to the pilot, at an altitude of 3,000 ft about 8 miles offshore while conducting fish spotting operations, the engine began to shake and lose rpm. To avoid ditching in the ocean waters, he navigated to the shoreline and the nearest airport. When it became evident that the airplane would not reach the airport, he ditched the airplane in the shallow waters of the ocean surf to avoid bystanders on the beach. The airplane sustained substantial damage to right elevator. Examination of the engine revealed that the No. 2 cylinder exhaust valve spring and guide had liberated and were located inside the damaged rocker cover. The piston and interior of the No. 2 cylinder exhibited mechanical impact damage and a hole was present in the face of the piston. The exhaust valve and exhaust valve keepers were not located. The reason for the liberation or failure of the No. 2 cylinder's exhaust valve could not be determined.

Analysis

Primary failure mode
Mechanical failure
First missed decision gate
Pilot could have conducted more thorough pre-flight engine checks.

NTSB coding

Evidence available

  • Photos
  • 3 docket documents
View NTSB final reportView NTSB docket

Docket documents3

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