Sunday dawned warm and sunny in the Cascade mountain range. Hikers and fishermen savored the beautiful weather that morning, sure they were far from the danger they knew had been rumbling for weeks now. But at 8:32 AM on May 18, 1980, an earthquake shuddered through Mount St. Helens which triggered the massive volcanic eruption which everyone had been waiting for -- and yet, in at least one major way, almost no one saw coming.

When LaMia Flight 2933 crashed in Colombia in November, the possible causes echoed a crash which occurred almost twenty-seven years ago in New York. Avianca Flight 52 came down on a slope in Cove Neck, Long Island in comparative silence, not bursting into flames as happens in so many crashes. The reasons why would lead to the industry considering the flaws in communication that can happen between flight crews and air traffic controllers.

On December 6, 1989, a man carrying a dark plastic bag containing a long object walked into the main building of Ecole Polytechnique, a suicide note in his pocket and hate for women in his heart. An hour and a half later he and fourteen women would be dead, inspiring changes in Canadian gun laws.

Love Parade was meant to be a celebration of peace, love, and understanding. The German electronic music festival was known for loud techno, colorful costumes, and sexual openness. But in 2010, the enormous event at an old freight station in Duisburg, Germany, ended with 21 people dead in a crushing incident on an entrance ramp.

This year is the 50th anniversary of the tragic events in the quaint mining town of Aberfan in south Wales. Days of heavy rain and an underground spring combined to turn a hillside tip into a dark sludge which slid down and plowed through the Pantglas Junior School, taking away a generation of the town's children.

On this episode, Jennifer uses the Movie Break she saved up for a special occasion to cap off a ridiculously awful week and watch "Airplane vs. Volcano." Keep liquor and the Internet Movie Database handy. If you can pronounce the name of the Icelandic volcano by the end of the episode, you're a better person than Jennifer.

Texas A&M's annual bonfire was meant to symbolize their burning desire to beat the hell out of the University of Texas at Austin's football team. But in 1999, Bonfire never burned. Instead it collapsed underneath the feet of several dozen students working to build the stack at the time, putting all of their lives at risk.

The worst single-plane loss of life in aviation history occurred on August 12, 1985, when a 747 loaded with holiday travelers crashed in the mountains near Mt. Fuji. The reason: A simple repair with a dangerous flaw.

At first, people who wandered over from Washington Square Park thought someone was throwing sack of shirtwaists out of the ninth floor windows of the Asch Building. But it quickly became apparent to the watching New Yorkers that these weren't bags of the Triangle Factory's finished products -- they were women. These young women had no other option, caught between the raging inferno blowing through the factory on March 25, 1911, and the ninth-story drop in front of them.

When children die in a disaster, it's the worst of tragedies. When children die due to the diabolical work of a man with dark intentions, it's even worse. May 18, 1927, was a typical spring day in Bath, Michigan, until a pair of explosions broke the day apart. One set the Kehoe farm alight. The other struck the Bath Consolidated School with devastating consequences.