EASA AD US-2023-04-08: Superseded by FAA AD 2023-05-16

What to do

Operators of affected Continental engines must inspect the crankshaft assembly for proper installation of the counterweight retaining rings before further flight starting February 23, 2023. If improper installation is found, corrective actions must be taken as specified in Continental Mandatory Service Bulletin MSB23-01A. Comments on this AD are accepted until April 10, 2023.

Summary

FAA Airworthiness Directive 2023-04-08 is a final rule addressing certain Continental Aerospace Technologies, Inc. reciprocating engines including models GTSIO-520, IO-360, IO-470, IO-520, IO-550, LTSIO-360, LTSIO-520, O-470, TSIO-360, TSIO-520, TSIO-550, TSIOF-550, and TSIOL-550. This directive requires inspection of the crankshaft assembly for proper installation of counterweight retaining rings due to a manufacturing quality escape. The AD aims to prevent engine oil pressure loss, catastrophic engine damage, and engine seizure caused by improperly installed counterweight retaining rings.

What changed

This new AD introduces mandatory inspection and corrective actions for the crankshaft counterweight retaining rings on affected Continental engines. Unlike the manufacturer's service bulletin, which limited inspections to engines with less than 200 operating hours, this AD requires inspection of all affected engines regardless of operating hours. The AD is effective immediately due to the urgent safety risk.

Why it matters

This AD is critical for aviation professionals because improper installation of counterweight retaining rings can lead to severe engine failures including in-flight engine oil pressure loss and engine seizure. Operators and maintenance teams must address this unsafe condition promptly to ensure continued airworthiness and flight safety. Compliance with this AD helps prevent catastrophic engine damage and potential loss of aircraft.