Wisk (Air Taxi)

Wisk, the Boeing-Kitty Hawk joint venture for autonomous air taxis, has spent over a decade and billions developing electric vertical takeoff aircraft without commercial operations. The company represents the gap between demonstration and commercialization in aviation—flying prototypes is far easier than meeting safety certification and building infrastructure. Like an organism that can survive in the lab but not in the wild, Wisk's technology hasn't reached viable deployment.