This paper reviews patterns of reported Unidentified Anomalous Phenomena (UAP) in the United States associated with specific types of UAP activity observed during the period 1945-1975. 
The nine specific types of UAP activity reviewed were: 

1.    interactive flight, 
2.    radical flight, 
3.    electronic transmissions, 
4.    interference with military weapons systems, 
5.    intrusions at military installations, 
6.    loitering, 
7.    close approaches, 
8.    observed occupants, and 
9.    encounters with occupants. 

Our previous studies for the same period focused on patterns (Hancock, et al, 2023a) and indications (Hancock, et al, 2023b) of UAP incidents reported to the U.S. military, particularly in the context of the development of the atomic warfare complex and the deployment of strategic atomic weapons  These studies analyzed activity based on location and association with military activities, which indicated an intelligent and focused survey of US atomic weapons development. 

While this study addresses a separate question to that of the previous studies, they use the same UAP report sources and there is an overlap of incidents between the three studies (Appendix 1).

A set of 505 UAP incidents were selected from Project Blue Book, the National Investigations Committee on Aerial Phenomena (NICAP), Clear Intent (Fawcett and Greenwood, 1984), and Faded Giant (Salas and Klotz, 2005). The incidents were chosen after a comprehensive investigation to ensure sufficient information was available to characterize the activities and that the incident displayed at least one of the nine specific types of UAP activity being studied.

During the early study period 1945-1960, most reports involved UAP being observed at a distance, during the daytime and with both the military and public. From 1960 onwards, the UAP reports shifted to close approaches during the nighttime and with the public. The public domain increases in reports from 1960 onwards included close approaches, occupant observed and occupant encounters. UAP occupant reports and reported messaging indicate intelligence; however, there are limited data with which to establish strong patterns and trends and further study is required. The military domain activity which focused on the locations of deployed atomic weapons continued throughout the study period.