What is the location requirement of an airworthiness certificate?

The correct answer indicates that the airworthiness certificate must be legible to both passengers and crew. This requirement ensures that relevant documentation is visibly available and easily accessible, which contributes to safety and transparency in aviation operations.

Having the airworthiness certificate displayed where it can be seen helps to confirm the aircraft's compliance with safety regulations and that it is fit for operation. This visibility fosters a better understanding among passengers and crew regarding the status of the aircraft, reinforcing confidence in its airworthiness and maintenance standards.

Though the other options suggest various locations where the certificate could be kept, they do not meet the regulatory requirement for accessibility and visibility to those on board the aircraft. For instance, while it’s important for pilots to have a clear understanding of the aircraft's status, simply having it in the pilot’s possession or in the maintenance logs does not satisfy the direct visibility requirement provided for all occupants’ awareness. Displaying the certificate ensures that everyone is informed and upholds the standards set by aviation authorities.