McDonnell Douglas MD 500 Defender

The McDonnell Douglas Helicopter Systems MD 500 Defender is a light multi-role military helicopter based on the MD 500 light utility helicopter.

Design and development
The original OH-6 Cayuse helicopter proved its worth during the Vietnam War in the light helicopter role. The designers at Hughes realized there was a market for a light multi-mission helicopter with an improved equipment fit than the OH-6 and Model 500M. The resulting design was the Model 500MD Defender which first flew in 1976. It was tailored for specific roles including unarmed observation and an armed scout helicopter equipped with TOW anti-tank missiles. An anti-submarine version was developed with a search radar, magnetic anomaly detector and the capability to carry lightweight aerial torpedoes.

The helicopter was popular with customers like Kenya who could buy a capable anti-armor helicopter for less than half the cost of a gunship such as the AH-1 Cobra or the AH-64 Apache. Israel used the Defender extensively during the conflicts of the late 1970s and 1980s against Syrian armored forces.

The Defender was later built as an improved version as the MD530MG, with increased engine power, handling, avionics, and a redesigned forward fuselage. Later developments included a mast mounted sight (MMS).

In December 2012, Boeing demonstrated their Unmanned Little Bird to the South Korean Army. The pilotless aircraft flew autonomously for 25 minutes. The purpose of the demonstration was to show unmanned capabilities technologies, such as enhanced ISR and resupply, in the system that could be integrated into Army MD 500 helicopters.

MD Helicopters had submitted a version called the MD 540F in the U.S. Army's Armed Aerial Scout program. This caused Boeing to try and block MD Helicopters from participating, citing agreements the companies struck in 2005 to offer the Mission Enhanced Little Bird in the Armed Reconnaissance Helicopter program. As part of the venture, MD Helicopters sold intellectual property related to the aircraft's design. The two companies lost the bid and the program was ultimately cancelled. When MD Helicopters disclosed plans to offer the MD 540F in the AAS program in April 2012, Boeing claimed that they could not sell any “similarly configured” aircraft to any U.S. or foreign military organization. Boeing is offering their AH-6 Little Bird in the competition. MD Helicopters said Boeing did not object to previous sales to armed forces and governments in Japan, Jordan, and Italy, as well as to U.S. special operations, and local U.S. police forces. Restrictions on selling aircraft similar to the Little Bird, domestically or to foreign users, would have put the company out of business. In July 2013, a federal court ruled that MD Helicopters could not be blocked from offering their aircraft.

Variants

 * 500D Scout Defender
 * Armed reconnaissance version


 * 500M Defender
 * Military export version of the 500 and 500C, built under license by Kawasaki in Japan (as the OH-6J) and Breda Nardi in Italy.


 * 500M/ASW Defender
 * Export version for the Spanish Navy.


 * NH-500M Defender
 * Italian-built version of the 500M Defender. Licensed by Breda Nardi before merge with Agusta.


 * 500MD Defender
 * Military version of the 500D.


 * 500MD/ASW Defender
 * Maritime version of the 500MD Defender.


 * 500MD/TOW Defender
 * Anti-tank version of the 500MD Defender, armed with TOW anti-tank missiles.


 * 500MD/MMS-TOW Defender
 * Anti-tank version, fitted with a mast-mounted sight, armed with TOW anti-tank missiles.


 * 500MD Quiet Advanced Scout Defender
 * Fitted with noise suppression equipment.


 * 500MD Defender II
 * Improved version.


 * 500MG Defender
 * Military version of the 500E.PhAF MD-520MG Helicopter.JPG


 * 520MG Defender
 * Philippine military version. Special Forces version, modified 500MG Defender to carry weapons and operate as a light attack aircraft.


 * 520MK Black Tiger
 * South Korean-built military version, built by Korean Air Aerospace Division, Korean Air's aerospace division from 1976 to 1984 with 200 choppers made. 50 were armed with TOW anti-tank missiles and 150 choppers used for transportation and support duties.


 * 530MG Defender
 * Military version of the 530F.


 * MD530 Nightfox
 * Night attack version.


 * MD530MG Paramilitary Defender
 * Police or border patrol version.


 * MD540F
 * Upgraded MD530F, incorporating a 6-bladed, fully articulated rotor blade system made of composite material, a more rugged landing skid for heavier take-off and landing weights, a fully integrated digital glass cockpit with multi-function color displays and a pilot Helmet Display and Tracking System (HDTS), which couples together a targeting FLIR and laser designator.

Operators
For civilian operators see MD 500 series

Military operators

 * Afghan National Army Air Corps
 * Argentine Air Force
 * Chilean Army
 * Colombian Air Force
 * Air Force of El Salvador
 * Finnish Army
 * Honduran Air Force
 * Italian Air Force
 * Japan Ground Self Defense Force
 * Japan Maritime Self Defense Force
 * Royal Jordanian Air Force
 * Kenya Army
 * Republic of Korea Air Force
 * Republic of Korea Army
 * Mexican Air Force
 * Mexican Naval Aviation
 * Servicio Nacional Aeronaval
 * $\phi$
 * Philippine Air Force
 * Republic of China Navy
 * United States Army (See A/MH-6)
 * Kenya Army
 * Republic of Korea Air Force
 * Republic of Korea Army
 * Mexican Air Force
 * Mexican Naval Aviation
 * Servicio Nacional Aeronaval
 * $\phi$
 * Philippine Air Force
 * Republic of China Navy
 * United States Army (See A/MH-6)
 * $\phi$
 * Philippine Air Force
 * Republic of China Navy
 * United States Army (See A/MH-6)
 * United States Army (See A/MH-6)
 * United States Army (See A/MH-6)

Former operators

 * Argentine Coast Guard
 * Croatian Air Force
 * Israeli Air Force
 * Croatian Air Force
 * Israeli Air Force
 * Israeli Air Force