The Sling 4-4-40 challenge, in which a Sling 4 was built in 4 days by 40 workers, marked yet another milestone for the Sling’s manufacturer, The Airplane Factory (TAF). The build, which normally takes a kit builder 1,000 hours to complete, took place at the 2014 Africa Aerospace and Defense Expo at the Waterkloof Air Force Base in South Africa. The team consisted of highly skilled workers, and even some marketing, admin and catering staff.