As I pointed out in a post written back in February 2020, Northrop entered the world of unmanned air vehicle development when it acquired the Radioplane Company of Van Nuys in 1952, capitalizing upon Radioplane's drone manufacturing business by developing the KD2R-5/MQM-36 Shelduck and XQ-10 piston-engine target drones, the supersonic jet-powered Q-4/AQM-35, and rocket-powered KD4R and AQM-38 drones, plus a number of advanced target drone projects. By 1962, however, the Radioplane Division of Northrop decided to move its headquarters from Van Nuys to the town of Newbury Park in Ventura County, and it changed its name to Northrop-Ventura after the relocation, opening up a new chapter in the history of drone development in the Los Angeles Basin. Northrop's drone-related business activities in Ventura County are largely overlooked in most published histories of the Southern California aerospace industry, but the Northrop-Ventura Division's most successful unmanned aerial vehicle ever produced was the BQM-74 Chukar. It is no wonder that I first saw this drone while visiting the San Diego Air and Space Museum in the 2010s, I had no idea that it was one of a few target drones built outside the Los Angeles metropolitan area, making it the most successful mass-produced Northrop drone design to be developed in the late Cold War. Given its distinction of being the only mass-produced target drone to built in a locality of southern California outside the Los Angeles and San Diego counties, I've opted to provide a comprehensive synopsis of the development, testing, production, and operational service of the Chukar.
 |
| A Northrop MQM-74A Chukar I on its ground-based launch platform |
In the early 1960s, the US Navy issued requirement for a small jet-powered aerial target to be used for anti-aircraft gunnery and missile training and system evaluation. Northrop-Ventura proposed a delta-winged target drone to meet this requirement, designated NV-105 by the company, and power was provided by one Williams J400 turbojet with an air intake slung under the fuselage. Four NV-105 prototypes were constructed, and flight tests began in 1964, but it was clear that the delta wing wasn't aerodynamically satisfactory, so a straight-wing NV-105 variant with a cigar-shaped fuselage was developed as the NV-105A, which made its first flight in 1965. After a few years of flight testing, the NV-105A was cleared for production and operational deployment with the US Navy in 1968 and designated MQM-74A. The Navy christened the MQM-74A the Chukar in reference to a species of partridge because just as a chukar can be hunted for sport, the MQM-74A could be deemed suitable to be shot at during gunnery training. Besides the cigar-shaped fuselage and straight wings, the MQM-74A had the horizontal stabilizers arranged in an inverted V-shape, and it was designed to be launched from land- or ship-based zero-length launch systems aided by two solid-fuel JATO rocket boosters. The MQM-74A featured a command guidance system, and the operator could track it either visually or through radar. When the command link was damaged, a parachute was deployed by remote command or automatically to allow for the drone to be recovered. Mission equipment of the MQM-74 included passive and active radar augmentation devices, wingtip-mounted infrared flares, a smoke system for visual augmentation, and tow targets; if a Chukar landed in the water, a floatation gear kit was provided for recovery. More than 2,000 MQM-74As were built, with the US Navy acquiring 1,800 of them, and hundreds more serving with the Royal Navy, Italian Navy, and a NATO test range on the island of Crete. Northrop proposed an improved version of the MQM-74A in the early 1970s with variable speed, designated MQM-74B, but this was never built. The MQM-74A Chukar I also formed the basis of the XBQM-108 unmanned tail-sitter VTOL research vehicle developed by the US Navy's Naval Surface Weapons Center (NSWC), which began tethered flight tests in late September 1976 but never made a free flight before the Navy canceled the XBQM-108 program.
 |
| Left: An MQM-74C on its launch platform, mid-1970s. Right: An MQM-74C being retrieved by crewmen aboard the drone recovery craft USS Retriever after a test launching in October 1984. |
The Navy was very impressed with the MQM-74A, but in the early 1970s it felt that it needed a slightly faster variant of the Chukar capable of attaining 576 miles per hour (926 km/h). Northrop responded with an slightly larger version of the MQM-74A powered by a higher-rated Williams J400-WR-401 (Model WR24-7) turbojet, which was designated MQM-74C by the Navy. The MQM-74C Chukar II began flight tests in 1973 and production of Chukar II started the following year, with deployment beginning shortly afterwards. A total of at least 1,400 MQM-74Cs built, mostly for the US Navy but also the armed forces of the United Kingdom, West Germany, Greece, Iran, Italy, Japan, Saudi Arabia, the Netherlands, and Spain. In 1975, the MQM-74C was selected by the US Air Force for the Tactical Expendable Drone System (TEDS) competition, and Northrop had four Chukar II drones modified for the TEDS requirement as the NV-130, which eliminated the parachute recovery equipment and carried more fuel space as well as electronic countermeasures systems. Tests of the NV-130 began in 1976 and continued until 1977, and even though performance results were seemingly satisfactory, the NV-130 did not enter production because the TEDS program was canceled due to a lack of funds. The US Army also took an interest in the MQM-74C and ordered a surveillance variant of the Chukar II, designated BQM-74D, which was fitted with a precision navigation system and sensors for target acquisition and battlefield surveillance. Although little is known about the developmental history of the BQM-74D, test flights of this variant took place in the mid-1970s but no production orders were placed.
 |
| Top: An air-to-air view of a BQM-74C Chukar III in flight Bottom: A BQM-74E Chukar III on display at the San Diego Air and Space Museum, photographed by me on August 24, 2019 |
Even as production of the MQM-74C began, in the mid-1970s Northrop envisaged a significantly improved version of the Chukar II, which became the BQM-74C Chukar III. Differences from the MQM-74C included a new cylindrical forward fuselage measuring 12 feet 11.5 inches (3.95 meters) in length, addition of the provision for air-launch capability, and a new microprocessor-based A/A37G-13 flight control system to enable much more complex pre-programmed flight profiles. The BQM-74C made its first flight in 1978 and following completion of flight testing the following year, production and deliveries of the Chukar III commenced in 1980, with the BQM-74C supplanting the MQM-74C in squadron service. Initial production BQM-74Cs used a Williams J400-WR-402 turbojet, which had slightly greater thrust than the J400-WR-401 that powered the MQM-74C, but beginning in 1986 all production BQM-74Cs were fitted with the J400-WR-403. For ground-based launches, the BQM-74C was fitted with a pair of MK 117 MOD 0 solid-fuel rocket boosters, which were jettisoned shortly after take-off once the target drone reached sufficient altitude. The main launch aircraft for the Chukar III was the DC-130 drone control version of the C-130 Hercules tactical airlifter, although the BQM-74C was also carried aboard the F-15 and F-16. Northrop developed a reconnaissance version of the Chukar III, the BQM-74C/Recce, which housed a TV camera in the nose and a video data link transmitter, and ten BQM-74Cs were converted to BQM-74C/Recce and tested in the mid-1980s, but this version was not procured by the Navy. During the aerial phase of Operation Desert Storm in January 1991, several BQM-74Cs were acquired by the US Air Force and modified as decoys by the fitting of a pair of corner reflectors to enhance the radar signature to imitate a manned aircraft, and these were used as decoys in the midst of US-led coalition airstrikes against Iraq under Project Scathe Mean of the USAF's Big Safari program, ensuring that the air forces of the US and its allies suffered minimal losses in the opening hours of Operation Desert Storm. Even before Operation Desert Storm began, an improved version of the BQM-74C with greater endurance, increased range as well as new-generation software, the BQM-74E, began flight tests in 1989/1990. Despite having the same length and wingspan as the BQM-74C, the BQM-74E uses an Williams J400-WR-404 turbojet delivering 240 lb (1.07 kN) and can fly at a top speed of 621 miles per hour (1,000 km/h), and it incorporates the latest target augmentation devices, namely the AN/DPN-90(V) radar tracking beacon, the AN/DPN-88 IFF transponder, the AN/DRQ-4 and AN/DSQ-50 scoring systems, the AN/DKW-3 and -4(V) target control transponders, and the AN/DPT-2 radar threat simulator. The BQM-74E, which retains the Chukar III moniker to emphasize it derivation from the BQM-74E, is air-launched from the DC-130 and simulates anti-ship cruise missiles as well as maneuvering attack aircraft. The BQM-74E entered service in 1992 and replaced the BQM-74C on existing production lines, and by the time that Chukar III production ended in the early 2000s, more than 2,000 BQM-74C/E target drones had been built and delivered. Before long, Northrop shut down its Ventura Division after the conclusion of the flight test program of the Tacit Blue stealth technology demonstrator in 1985, leading to the relocation of production facilities for the BQM-74E to Hawthorne in the early 1990s and thence to Palmdale in 2002.
 |
| The BQM-74F, the last Chukar variant to be built |
Although Northrop Grumman's drone manufacturing business in Ventura County was consigned to the dustbin of history, one more BQM-74 variant was developed in the late 1990s, initially marketed by the company as Target 2000 and later designated BQM-74F in March 2002 when a development contract was awarded. The BQM-74F differs from the BQM-74E with having backswept wings spanning 7 feet (2.1 meters), a length of 15 feet (4.5 meters), a top speed of Mach 0.9, a range of more than 1,037 miles (1,670 km), greater maneuverability, an endurance of two hours, and a drastically uprated William J400 turbojet delivering 300 lb (1.32 kN) of thrust. Novel electronic systems fitted to the BQM-74F include a IMU/GPS-based waypoint navigation system as well as new mission planning software (allowing in-flight modification of all parameters). The BQM-74F first flew on August 29, 2005, entering service with the US Navy in 2010, and more than 100 BQM-74Fs have been built. Although the BQM-74E still serves with Navy units despite having been phased out of production in the early 2000s, is it currently being replaced in frontline service by the Kratos BQM-177, which has greater range, maneuverability, and speed than the Chukar and features a new fuselage with area ruling.
References:
Munson, K., 1988. Jane's World Unmanned Aircraft. Coulsdon, UK: Jane's Information Group.
Munson, K., 2000. Jane's Unmanned Aerial Vehicles and Targets, Issue 15. Coulsdon, UK: Jane's Information Group.
Yenne, B., 2012. US Guided Missiles: The Definitive Reference Guide. Manchester, UK: Crecy Publishing.
