Complex sentence: The Mountaineers are the first FCS team to win three straight national championships since the creation of Division I-AA in 1978, and are the first Division I program to win three consecutive national championships since Army accomplished the feat in 1944,1945, and 1946.
Split into simpler sentences: The Mountaineers are the first FCS team to win three straight national championships since the creation of Division I-AA in 1978. They are also the first Division I program to win three consecutive national championships since Army accomplished the feat in 1944,1945, and 1946.