Specifications for an aircraft model with fewer than 50 units registered can be found in which document?

The Aircraft Listing is the correct document to reference for specifications on an aircraft model that has fewer than 50 units registered. This listing includes detailed information about various aircraft types, including their specifications and performance data. The Aircraft Listing is particularly important for smaller or less common models, as it consolidates critical information that might not be as widely available in other sources.

While the FAA Advisory Circular provides guidance and policy information on a wide range of aviation topics, it does not typically contain specific aircraft details or listings. The Pilot's Handbook focuses primarily on pilot operating procedures, flight techniques, and general flying considerations rather than technical specifications for aircraft. The Maintenance Manual contains maintenance requirements and procedures but would not generally provide the broad array of specifications necessary for understanding an aircraft model's capabilities or design in detail. Therefore, the Aircraft Listing is the appropriate source for this information.