The term 'Military Attack Helicopter' can be broken down into two crossword solutions: VIPER (5 letters) and APACHE (6 letters). The Boeing AH-64 APACHE is a four-blade, twin-turboshaft attack helicopter with a tailwheel-type landing gear arrangement. It features a nose-mounted sensor suite for target acquisition and night vision systems. The Bell AH-1Z VIPER is a twin-engine attack helicopter based on the AH-1W SuperCobra. It has upgraded avionics and weapons systems, including a modern digital cockpit, and is capable of carrying a variety of weapons. Both helicopters are used by the US military and other countries for attack missions.