AAIB investigation to Grob G 120TP-A, G-ETPC

Propeller oil leak in-flight, RNAS Yeovilton, Somerset, 15 September 2021.

• From: Air Accidents Investigation Branch
• Published: 9 June 2022

• Category: General aviation - fixed wing
• Report type: Bulletin - Correspondence investigation
• Date of occurrence: 15 September 2021
• Aircraft type: Grob G 120TP-A
• Location: In flight, RNAS Yeovilton, Somerset
• Registration: G-ETPC

Summary:

During a training flight, forward visibility was obscured when engine oil leaked from the propeller onto the windscreen. The pilot made a successful precautionary landing using full sideslip to enable him to use the only part of the windscreen that was clear.

An examination of the propeller revealed a damaged piston seal. The aircraft manufacturer had previously issued a Service Letter regarding oil leaking from the piston seal and following this event the propeller manufacturer issued a Service Bulletin to inform operators of an improved O-ring seal with increased durability.

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Grob G 120TP-A, G-ETPC 06-22

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Glossary of abbreviations

Published 9 June 2022