US Air Force/Master Sgt. David Kujawa The HGU-55/P helmet gives A-10 pilots a central interface for everything they need, from their oxygen supply to communications to flight instruments. One of those add-ons, the Hybrid Optical-based Inertial Tracker, or HObIT, allows pilots to use their helmet-mounted cueing system for more accurate weapons delivery. Visit Business Insider's homepage for more stories. Most people have worn a helmet, whether for sports or riding a bike, but probably nothing like the helmet A-10C Thunderbolt II pilots use to connect them to their aircraft. The HGU-55/P helmet provides A-10 pilots a central interface for everything they need, from oxygen supply to communications to flight instruments. "The helmet is a multi-faceted tool that provides protection and life support as a baseline," said 1st Lt.