After Lockheed was requested on 27 June 1980, to begin preliminary engineering studies on an STOL Hercules, the use of JATO units was explored, since these had previously been used to power takeoffs. Lockheed reported on 16 July that 58 JATO bottles (more than seven times greater than normal) would be required and that arresting gear would be insufficient to stop the C-130 in the required space. The U.S. Navy's Naval Air Weapons Station China Lake organization was then brought into the project to provide expertise on existing rocket motor power. Lockheed proceeded with work to structurally reinforce the C-130 airframe to withstand rocket forces and to develop a passenger restraint system for 150 persons.