Vision Systems International (VSI) said its F-35 Helmet Mounted Display (HMD) was successfully demonstrated in a series of flights performed by the Royal Air Force Centre for Aviation Medicine (RAF CAM). VSI, a joint venture between Israel-based Elbit Systems and Rockwell Collins, said the test pilots employed the F-35 HMD while flying two specially modified BAE Hawk T Mk1 aircraft. Pilots from the RAF, U.S. Air Force, Lockheed Martin and BAE Systems have taken the helmet from minus 2 to plus 9 Gs in flights designed to simulate air combat. VSI said the pilots' assessments were the HMD shows significant promise given its comfortable fit and the solid, stable symbology provided throughout the flight envelope. RAF CAM offered to evaluate the VSI HMD on the Hawk platform, which is capable of up to 9.5 Gs. Additional flights with the VSI HMD are planned in September and October.