CESSNA 421 TURBINE — Flight Manual

This document is a Service Bulletin issued by Kelly Aerospace Power Systems regarding potential interference issues with turbocharger turbine exhaust outlet flanges on various Cessna aircraft models, including the Cessna 421 Golden Eagle. It highlights the risk of exhaust leaks due to improper flange alignment and mandates inspections and possible replacements of affected turbocharger turbine housings. The bulletin is aimed at maintenance personnel and emphasizes compliance within a specified timeframe to ensure safety and operational integrity. It includes detailed procedures for inspection, repair, and return to service, along with necessary materials and warranty information.

• Turbocharger turbine housings manufactured between August 25, 2006, and January 25, 2008, may have interference issues.
• Compliance is required within 10 hours of service or at the next scheduled maintenance.
• Inspect the gap between the turbine housing flange and exhaust tube flange; it should not exceed .005 inch.
• If the gap exceeds tolerance, the turbocharger must be replaced following specific procedures.
• Use only certified parts and follow the manufacturer's maintenance manuals for repairs.