Cessna 411 — Service Bulletins

This document is a proposed Airworthiness Directive (AD) issued by the Federal Aviation Administration (FAA) that addresses safety concerns regarding Cessna Models 401, 401A, 401B, 402, 402A, 402B, 411, and 411A airplanes. The directive aims to prevent wing spar cap failure due to undetected fatigue cracks, which could lead to loss of control of the aircraft. The document outlines the required inspections and modifications necessary to ensure the structural integrity of the wing spar caps. Compliance with the AD is mandatory for all operators of the affected aircraft models, and it details the specific actions that must be taken, including inspection intervals and repair procedures. The AD is a response to previous findings of fatigue cracks in the wing structures of these aircraft models, emphasizing the importance of regular maintenance and adherence to safety protocols.

• This AD applies to Cessna Models 401, 401A, 401B, 402, 402A, 402B, 411, and 411A.
• Operators must inspect wing spar caps for fatigue cracks and repair or replace as necessary.
• Initial inspections for Models 411 and 411A are required at 5,500 hours TIS or within 200 hours after the AD's effective date.
• Failure to comply may lead to catastrophic wing failure and loss of control.
• Alternative compliance methods can be proposed to the FAA.