The Bombs

The Columbine Attack

Eric Harris and Dylan Klebold planned Columbine primarily as a bombing.  The timers were set to begin with the eruption of two big propane bombs in the cafeteria at 11:17 a.m. That was the start of "A" lunch, the maximum human density anytime, anywhere in the school on any given day.  Maximum body count. 

Eric and Dylan then intended to open fire at fleeing survivors (guns here).  They also loaded their cars with bombs and gasoline, set to detonate about noon. 

These are the official Jeffco sheriff's photos of the big bombs.  All failed. ( Only the pipe bombs worked.  The "diversion" bomb in a field ignited its detonator and started a grass fire, but also failed to explode.) 

Explanations appear below the photos.