The Hughes/McDonnell-Douglas MD-500/530 series civil helicopter is a very popular version in the US & world helicopter market, well regarded as one of the best small size multi-purpose helicopter. Soon the company provided the MD500/530 Defender series of military variations. The fuselage of the military variations are the same with the civilian ones, excpet the TOW Defender. The US Army named these variations OH-6 Cayuse, AH-6 and MH-6, nickname "Little Bird".
休斯/麦道 MD500/530 系列民用直升机是美国乃至国际直升机市场中非常受欢迎的一种型号，被认为是最优秀的多用途直升机之一。 MD500/530 “防御者”是原美国休斯直升机公司(1985年8月27日并入麦克唐纳?道格拉斯公司)在其MD500/530民用型系列直升机的基础上发展起来的军用型。除“陶”“防御者”外，其机体与民用500/530型相同。美陆军编号为 OH-6 “小马”， AH-6 和 MH-6 ，绰号“小鸟”。
