For a team that throws it as much as Texas Tech does with Mike Leach, I get a surprising number of questions about the Airraid run game. The reason, I suppose, is that if you throw the ball a lot you need a good complementary run game that will take advantage of the defense when it overreacts to your passing game but also doesn't require too much practice time.
This topic deserves a fuller discussion later, but I was sparked when I saw these clips of Texas Tech's spring football. Video below (hat tip Tortilla Report via Double-T Nation):
Okay, you might be saying, I see some guys running around, but what does it mean? Again, this topic deserves a fuller treatment, but here's some diagrams and quick explanations of Leach and Texas Tech's main run plays.
Base
Base is essentially a "man" blocking run play that has each lineman block the man over them, and if uncovered, they head up to the linebackers. (The "fold" technique comes into play where there is a sort of "shaded" nose -- a defensive tackle who would be too difficult to "reach" for the guard -- so they can make a "fold" call at the line.) The play is easy to teach because it uses largely the same scheme as their main pass protection (big on big; back on backer) but uses drive blocking. Finally, this play is often mistaken for a "draw" -- it just looks like one when run from the shotgun.
Lead
"Lead" is your basic "isolation" play: all the linemen block "man on" or "down" and the lead blocker bursts into the hole and blocks the first man that shows; the ball carrier then cuts off the lead back's block. Tech uses this a lot when they get into any two-back set (whether from gun or those rare times under center). From shotgun this too looks a lot like a "lead draw," but it is really just one of the oldest plays in football run from Tech's funky wide line splits and shotgun.
Stretch
The "stretch" has increasingly been a weapon for Leach over the past few years. A big reason is that Leach is now fully committed to the wide line splits, so at some point in the game the defensive ends tend to stop lining up so far outside the offensive tackles and instead line up heads up or inside them, thus giving the offensive guy an easy "reach" block to hook the defender inside. As a result the runningback has an easy spring to the outside.
Conclusion
Leach's run game is not complicated and no one will confuse Tech with Paul Johnson's flexbone option teams, but they have had decentbalance (depending how you define it) over the years and the run plays are some of the most tried and true schemes around. He just uses them from his spread sets, and only when the defense is completely stretched out.