The Menace of "Aerial Bombs"

A new weapon in the terrorist arsenal that has the Pentagon concerned:

American helicopters in Iraq are facing a new threat from so-called aerial bombs, which are fired into the air from the ground and explode close to passing aircraft.
The new home-made weapons, known to the Americans as "aerial improvised explosive devices" have been used on numerous occasions.

...The aerial devices are placed along known flight paths and are triggered when insurgents see a low-flying helicopter approaching.
They are then fired to a height of about 50ft before a proximity fuse detonates the explosive, filling the air with thousands of metal shards.
Based on old anti-aircraft or artillery shells, the bombs would have a devastating effect if detonated close to a thin-skinned helicopter.

Here's DefenseTech on the story.