Service academies are a long-standing tradition in college football -- no matter how Army, Navy and Air Force are doing, any games between the three schools are national events. Those three programs have struggled at times to keep up with the evolving landscape of college football, but they've had some highly successful teams over the years.

The top 15 is above, and here's the full top 25, based on Sports-Reference.com's SRS rating:

Rank Team SRS 1 1945 Army (9-0, No. 1 AP) 33.35 2 1944 Army (9-0, No. 1 AP) 32.17 3 1946 Army (9-0-1, No. 1 AP) 30.44 4 1945 Navy (7-1-1, No. 3 AP) 28.92 5 1944 Navy (6-3, No. 4 AP) 23.19 6 1943 Navy (8-1, No. 4 AP) 22.07 7 1949 Army (9-0, No. 4 AP) 20.72 8 1958 Army (8-0-1, No. 3 AP) 19.98 9 1957 Navy (9-1-1, No. 5 AP) 19.71 10 1917 Navy (7-1, No AP poll) 19.56 11 1950 Army (8-1, No. 2 AP) 19.24 12 1954 Navy (8-2, No. 5 AP) 18.74 13 1948 Army (8-0-1, No. 6 AP) 18.67 14 1941 Navy (7-1-1, No. 10 AP) 17.98 15 1947 Army (5-2-2, No. 11 AP) 17.24 16 1963 Navy (9-2, No. 2 AP) 17.07 17 1918 Navy (4-1, No AP poll) 17.03 18 1985 Air Force (12-1, No. 4 AP) 16.36 19 1922 Army (8-0-2, No AP poll) 15.68 20 1901 Army (5-1-2, No AP poll) 15.35 21 1970 Air Force (9-3, No. 16 AP) 15.20 22 1897 Army (6-1-1, No AP poll) 15.16 23 1934 Navy (8-1, No AP poll) 15.09 24 1943 Army (6-2-1, No. 11 AP) 14.76 25 1913 Navy (7-1-1, No AP poll) 14.75

The peak period for service academy success quite clearly came during World War II. Many other schools stopped fielding teams during the war, leaving Army, Navy and a number of new service teams as football's elite. In the final 1944 poll, more than half of the 20 teams ranked were service academies or service teams. That 1944 season also included top-ranked Army (second on our list) and second-ranked Navy (fifth) squaring off in a game for the ages. World War I was a peak time as well for similar reasons, with two teams from that period making it into our top 17.

Air Force's presence is limited, but Fisher DeBerry's 1985 season deserves special recognition.The Falcons lost just one game, a 28-21 loss to BYU in Provo, and beat Texas in the Bluebonnet Bowl. Considering the program began in 1954 and is located in remote Colorado Springs, it's remarkable that the Falcons have been able to field a competitive football program in the first place.

High-level success has become more and more difficult for the service academy programs in recent years, although the Midshipmen and Falcons have been able to earn bowl berths fairly consistently since the turn of the century. We talked with the coaches of Army, Navy and Air Force about their difficulties recruiting and maintaining a program.