關於美國正在研發的人工智能無人戰鬥機，我們可以問問美國人工智能聊天平台ChatGPT。這是答案：

As of my knowledge cut off in 2021, the following are some of the unmanned fighter jets currently in development in the United States:

1. XQ-58A Valkyrie: Developed by Kratos Defense & Security Solutions for the US Air Force Research Laboratory, the XQ-58A is a long-range, high-altitude unmanned aerial vehicle (UAV) designed for reconnaissance and strike missions.
2. Sea Guardian: The Sea Guardian is a long-range, maritime unmanned aerial system (UAS) developed by General Atomics Aeronautical Systems for the US Navy. It is designed to provide intelligence, surveillance, and reconnaissance capabilities in support of naval operations.
3. Skyborg: Developed by the US Air Force, Skyborg is an autonomous unmanned aircraft system that will be integrated with manned aircraft to increase their capabilities and improve decision-making in combat situations.
4. MQ-25 Stingray: Developed by General Atomics Aeronautical Systems for the US Navy, the MQ-25 is a carrier-based unmanned aerial refueling system designed to increase the range and endurance of manned fighter jets.