Which document should be referenced to verify eligibility for ski installation on an aircraft?

The type certificate data sheets are the appropriate document to reference for verifying eligibility for ski installation on an aircraft. These data sheets provide critical information about the specific aircraft model, including its approved configurations, performance characteristics, and limitations. When considering modifications such as ski installations, it's essential to refer to this documentation to ensure that the changes comply with the approved design and do not adversely affect the aircraft’s safety and airworthiness.

The other options, while important in their respective contexts, do not specifically address modifications like ski installations. The aircraft airworthiness certificate confirms that the aircraft meets the regulations for safe operation but does not detail specific equipment or modification approvals. Advisory Circular 43.13-2A provides guidance on acceptable methods for maintenance and alterations but isn’t specific to eligibility for particular installations. The aircraft operating manual offers operational procedures but does not specify modifications or equipment compatibility. Hence, for regulated modifications, consulting the type certificate data sheets is essential to ensure compliance with established design standards.