Pentagon investigators found that October’s runaway Army blimp was the result of several incidents with mounting consequences that, like falling dominos, escalated before any military personnel could react. The report on the sequence leading up to the blimp’s great escape is very much a recipe for disaster.

Last fall, a military blimp stationed in Maryland broke free of its tethers and roamed the East Coast, leaving hundreds of thousands in property damage in its wake. The ensuing goose chase made headlines and convinced the Pentagon to kill the blimp program once and for all.

So what was it that caused the blimp to go AWOL on that fateful October day?

1) A malfunctioning tube. The blimp’s pitot tube measures air-pressure within the vessel. However, the tube in this particular blimp was broken and no one had yet taken the time to fix it.

2) Unresponsive fans. When the atmosphere changes, the pitot tube signals a set of fans to regulate the internal pressure of the blimp. Since the tube wasn’t working, the fans didn’t activate and stop the blimp’s air pressure from plummeting.

3) A perpendicular position. Ideally, a tethered blimp will be parallel to the direction of the wind in order to protect its tail fins. This blimp was facing the wrong way, so its tail fins were mangled, rendering the entire aircraft unstable.

4) Dead batteries. The blimp’s last failsafe was an automatic-deflation device that would release air in the event the aircraft was suffering from pressure or mechanical problems. But the device didn’t activate–no one had changed the batteries.

Throw in some 67 mph gusts, and you have an unpiloted, runaway Army blimp.

The Pentagon hasn’t identified the serviceman who failed to replace those crucial batteries.