What does a D NOTAM include information about?

A D NOTAM, which stands for "Distance NOTAM," is used specifically to convey information that is critical to the safety of flight, particularly regarding the status of aeronautical facilities. It provides updates on significant changes that could affect flight operations, especially concerning the availability of airfields, runways, navigation aids, and other essential infrastructure.

Given this context, the selection of airfield and navigation aid information as the answer highlights the primary purpose of a D NOTAM. It serves to inform pilots about operational status or changes at airports and navigation aids, which are crucial for flight planning and navigation.

The other options involve important aspects of aviation but are not the focus of D NOTAMs. Regulations regarding Temporary Flight Restrictions (TFRs) pertain to airspace management and control, while real-time weather updates, although crucial for operational safety, are typically disseminated through different sources such as METARs or TAFs. Emergency procedures for aircraft relate to response protocols but are outlined in other documentation such as the aircraft's operating handbook and are not the primary function of a D NOTAM.