Previously: Air Force Offense

LB Grant Ross is Air Force's only returning defensive starter.

Under Troy Calhoun and defensive coordinator Steve Russ, Air Force has devised a defense intended to turn opponents into the polar opposite of Air Force. The Falcon offense, as covered yesterday, is designed to be as efficient as possible, moving the ball in chunks on the ground with only the occasional big-play attempt through the air.

To complement that offense, AF fields a hyper-aggressive defense hell-bent on stopping the run, generating sacks and turnovers, and forcing the offense to rely on big passing plays while under heavy duress.

This makes for some crazy numbers. The Falcons had the #9 rush defense and #99 pass defense by S&P+ last year. They ranked 26th in success rate (a measure of efficiency) and 124th in isoPPP (a measure of explosive plays). They were 15th in preventing plays of 10+ yards (152) and 119th in preventing plays of 20+ yards (76).

I revisited last year's game against Boise State for this post, and BSU's drive chart is a good demonstration of what can happen when this defense is clicking. After BSU broke a big run on their opening drive to set up a short touchdown, AF loaded up the box, brought a ton of heat, and knocked the Broncos off schedule. Their drives:

• 2 plays, 60 yards (56 on one run), touchdown
• 6 plays, 20 yards, punt
• 3 plays, 2 yards, punt
• 3 plays, 5 yards, punt
• 3 plays, 0 yards, punt (blocked for AF TD)
• 4 plays, 10 yards, punt
• 8 plays, 59 yards (43 on one pass), field goal
• 3 plays, 6 yards, punt
• 11 plays, 78 yards (57 on one pass), field goal
• 3 plays, -4 yards, punt
• 1 play, 75-yard touchdown pass
• 6 plays, 89 yards (passes of 39 and 47 yards), fumble on 4th-and-goal

Air Force successfully made Boise State into a big-play-or-bust outfit, and while it got a little hairy at the end, it resulted in a 27-20 upset win.

Personnel: Seth's diagram [click to embiggen]:

Yes, that's one returning starter. There's a reason this post focuses entirely on scheme. Since I watched a game from last season and Air Force's week one opponent this year was a very overmatched VMI squad, we didn't hand out any stars or sore spots.

Base Set? Air Force lists themselves as a 3-4 but this is really a 3-3-5, what with the 263-pound nose tackle and 205-pound outside linebacker. They make up for their lack of size by loading the box with eight or nine guys on most snaps:

That's a safety lined up two yards off the LOS to the top of the screen and the free safety is creeping within seven yards at the snap even though he's responsible for the deep middle.

[Hit THE JUMP for the rest of the breakdown.]

Man or zone coverage? Mostly cover one, with man across the board and a deep safety in the middle of the field. They played quite a bit of press in this game, which threw off Boise State's timing enough that they missed some open receivers. Their goal is to speed the quarterback up with pressure and force quick, tough throws. This puts a lot of pressure on their corners to hold up in coverage and also asks a lot of their safeties. Watch #8, lined up as essentially an extra linebacker on the near hash, hang in there for the run fake before bailing into his zone just in time to get under an otherwise open route:

They got into trouble when playing off coverage, most notably on the 75-yard second-half touchdown. The corner to the bottom of the screen fakes a blitz, backs out, and gets burned to a crisp on a simple post route:

There will be times when Wilton Speight doesn't have an open receiver before the blitz hits home; there will also be times when he has a touchdown handed to him so long as he gets through his progression in time. Taking advantage of those opportunities is the key to keeping this from being a hold-onto-your-butts experience.

Pressure: GERG or Greg? You can guess by now. Air Force isn't going to fool you much on the back end, but they'll make life hard for the guys up front with myriad blitzes from their linebackers and safeties. This is a typical passing down:

Cover one, five rushers attacking at the snap, one more coming on a delay when the back stays in to block. The Falcons like to send delayed blitzers when their assigned man doesn't go into a route, so their pressure often comes in waves—that won't give Speight much time to shake off a rusher, reset, and still get a throw off downfield. The offensive line and backs will need to pick up a lot of different blitz looks; last week's twists that initially befuddled the right side of the line was good practice.

OVERVIEW

This defense is dead simple: man across the board with a deep safety who may not be very deep at all, aggressively stop the run, gun for sacks and turnovers to even out the inevitable big plays.

I'm expecting Jim Harbaugh to try to overpower a small Air Force front, at least initially. That may not be so easy despite M's physical advantage, however, as AF will throw as many bodies as necessary into the box to keep their opponent from establishing the run. Sometimes they'll get caught in the wash or overpursue and open up cutback lanes, which happened on Boise's very first carry of the game:

The issue for Boise was sustaining that success. Their running back covered 56 yards on that carry; his other 21 carries netted 32 yards. Air Force played very sound, aggressive run defense, daring Boise to try shots over top.

Those weren't particularly easy to hit because Boise couldn't consistently keep the pocket clean; while BSU didn't allow a sack, pressure impacted several throws. It didn't help that either the QB or WR was slightly off on a few quick-hitting slants that could've gone for big plays; one throw was flat missed, while another couple were dropped.

Michigan should be in better position to hit those big plays. Here's an instance when Air Force overcommitted to a play-action fake and had to take an obvious holding call to prevent a tight end from running free up the seam for a probable touchdown:

You can see the whole dang defense step up on the run fake. That isn't an accident, that's how Air Force plays; their safeties were usually pretty good at stepping up and then bailing out if it was a pass. The safety's second false step here is what opens up the seam. Notably, Air Force has an entirely new secondary and lost a couple quality safeties in Brodie Hicks and WESTON STEELHAMMER. There will be busts.

This matchup is a little tough to predict since Air Force turns over almost literally their entire defense, but this can go three ways.

1. Despite Air Force's best efforts, Michigan grinds out a decent running game anyway. If this happens, it'll be a blowout.
2. Air Force successfully slows the run by overcommitting but in doing so allows a series of big plays through the air. Michigan wins comfortably.
3. Air Force successfully slows the run by overcommitting and Michigan fans tear their hair out as Speight isn't accurate enough to take advantage and/or the line is overwhelmed by the constant pressure. Hold onto your butts.

Given Michigan's sheer size and talent advantage, I'm inclined to think the first two possibilities are the most likely, but we unfortunately can't rule out #3 given Speight's (and the OL's) uneven start to the season. Even if Speight is off, however, I believe Harbaugh and Co. will scheme up enough quick-hitters to M's superior athletes to put a healthy number of points on the board. Air Force plays with fire by design; that's a tough way to live against a coach who can adjust as well as Harbaugh.