Army Black Knights 3-4 Flex Defense (1999) - John Mumford

The defensive coordinator for the 1999 Army Black Knights was John Mumford. He was a former player and assistant coach at the University of Notre Dame. He was known for his aggressive style of defense and his ability to get the most out of his players.

Mumford's defense was a 4-3 defense that was designed to pressure the quarterback and force turnovers. The defense was led by a number of talented players, including linebacker Rob Waldrop, who won the Outland Trophy and was named the Pac-10 Defensive Player of the Year.

The Black Knights' defense was very successful in 1999. They led the nation in turnovers forced with 40, and they also allowed just 14.8 points per game, which was the second-fewest in the country.

The 1999 Army Black Knights football team was a team that was led by a strong defense and a young, inexperienced offense. The team finished the season with a record of 3–8, but they were competitive in most of their games. They were also invited to the Independence Bowl, where they lost to the Utah Utes, 27–16.