An AH-64E Apache attack helicopter parked on a tarmac.

US Army National Guard photo by Edwin L. Wriston

The AH-64 Apache is one of the most advanced attack helicopters in the world, but even this battle-tested gunship is vulnerable to the growing airborne threats to combat aircraft.On Tuesday, the US military revealed that an AH-64 Apache helicopter went down off the coast of Oman while patrolling regional waters amid the US war with Iran. Later reports indicated that it was brought down by an Iranian drone.The helicopter's two crew members were rescued safely. A new naval drone, a Saronic Corsair, was deployed to rescue them, marking an operational first for the military. US forces responded to the downing of the Apache with retaliatory strikes against Iran.Here's a closer look at the AH-64 Apache attack helicopter, a versatile combat platform that the US Army has been using to patrol the seas and target Iranian ships near the Strait of Hormuz.

The AH-64 Apache is one of the world's most advanced attack helicopters.

An AH-64E Apache attack helicopter.