MD 500D

The MD 500D, originally developed by Hughes Helicopters in the early 1970s, is a light utility and attack helicopter that evolved from the legendary OH‑6A Cayuse. Introduced in 1979, the D model incorporated a more powerful Allison 250‑C30 engine, a lengthened fuselage, and reinforced transmission, giving it a maximum take‑off weight of about 4,200 pounds and a top speed near 170 knots. The airframe features a fully articulated three‑blade rotor system with composite blades, providing excellent maneuverability and low vibration levels. Avionics were upgraded with a digital cockpit, night‑vision compatible lighting, and optional weapon stations such as machine‑gun pods, rocket launchers, or anti‑armor missiles, making the MD 500D a versatile platform for law‑enforcement, reconnaissance, and close‑air support missions. Its compact size and ability to operate from confined urban environments earned it a strong reputation among military and civilian operators worldwide. Over 600 units were built before production shifted to the MD 530 series, and the D variant remains in service with several armed forces and security agencies, illustrating its lasting impact on light‑helicopter design and mission flexibility. The MD 500D continues to influence modern rotorcraft concepts and is often used in training programs to demonstrate advanced flight control techniques.