Atlanta Airport

Yesterday it seemed to be a big story. Today it's basically disappeared. The first reports were of a grenade of some type attached to a cell phone, similar to those devices used in Spain last month. The stories were everywhere, with pictures of bomb squad members removing a bag from a restroom and talk about how the device was so much like the suspected al Qaeda devices on the Spanish rail line on March 11.

Today, I had to search for stories, most of them from last night, on Google News. Why the change?

It seems that there was no grenade and no cell phone either. Just a "trip flare" and some other "attachments." A fire hazard, perhaps, but no real danger, right? Not so fast.

I've used trip flares. They are activated when the pin, attached to a wire stretched across a path, is pulled, igniting the flare. Infantry troops set them out to "cover" avenues of approach that they cannot see directly or that are not the main approach for the enemy. Used properly they are not a danger to most people.

The problem with this story disappearing is that in the context of something like this getting on board an aircraft, they are exceptionally dangerous. Here's why:

There are two basic types of trip flares, one that when activated, burns in-place, illuminating the immediate. The other launches a small rocket with a flare that parachutes down, illuminating a larger area. The big problem in this case is what burns. It's magnesium powder; which burns at around 2,000 degrees Fahrenheit. In the hold of an aircraft or in a bathroom on board, the burning magnesium would burn through the aluminum skin of the aircraft. At a minimum, this would cause the pressurized cabin to explosively decompress. If attached to the right place on the aircraft, it could burn through cables or hydraulic lines for critical controls. It's hot enough to actually set the aluminum on fire.

No one has said what the other attachments were yet. A two-way radio? A cell phone?

It's unlikely someone would go through the trouble and the risk of smuggling such a device into Hartsfield Airport just to start a bathroom fire.