DC-130
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The DC-130 is a variant of C-130 Hercules, designed for drone control. It can carry four Firebee drones underneath its wings.
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[edit] Development
[edit] Origin of the Design
Ever since World War I, many nations' air forces have investigated different means of remotely controlling aircraft. Spurred by the U-2 Crisis of 1960, the United States Air Force gained a renewed interest in using drones, or more popularly, Unmanned Aerial Vehicles to gain intelligence on the SA-2 Guideline Surface-to-air missile system. Under the code names "Lightning Bug" and "Compass Cookie", some Ryan 147A target drones were modified for the reconnaissance mission. The drones were test flown over North Korea and China after the Gulf of Tonkin Incident in August, 1964.
While perfect for reconnaissance, the use of a mere radar van for command, track and control limit the combat ability of the drones. The team controlling the drones was limited to a single, stationary recovery area. In order to improve the range and recoverability of the drones, some C-130As were modified to carry the drones on pylons under the wings and were re-designated as GC-130, MC-130 or DC-130.
The DC-130H project was tested at Hill AFB, UT with the 6514th Test Squadron. The aircraft was designed to carry and deploy up to four drones. In addition to its ability to deploy four drones, it could also provide control for up to 16 drones simultaneously.
[edit] Operational Use
The Strategic Air Command had the DC-130s assigned to the 100th Strategic Reconnaissance Wing from 1966 throuigh 1976, when the 100th's drone assets were transferred to the 432nd Tactical Drone Group of the Tactical Air Command. The 100th was then re-designated as the 100th Air Refueling Wing.
Target or strike (weapons carriers) drones were carried on two pylons located under each wing: one between the engines and one on the outboard of the engines. This allowed the DC-130 to carry and control four drones simultaneously. These were never deployed operationally. Only reconnaissance and electric warfare types were used in the field.
DC-130 can launch, track and control the drones. The aircraft contained two launch stations (one for each drone) from which all systems on the drone were activated and checked. From those stations the engines were started, run through their checks and stabilized at the correct power setting for launch. A two-man station, just aft of the flight compartment, contained all the tracking and control functions. Instruments displayed all data transmitted from the drone—such as heading, speed, altitude, power setting and flight attitudes. Navigation and tracking data were fed to a system that plotted the current position of both the drone and DC-130 on a large map board in front of the operators. The planned track of the drone was drawn on the board, which enabled the crew to immediately detect any deviation in the drone's flight path. The drone controllers monitored and recorded video data from drones equipped with TV cameras and recorded any other data collected by other special-purpose drones.
The DC-130 was used in Senior Prom, a program to develop stealthy cruise missiles in 1978.
[edit] Upgrades
Reconnaissance drones were much larger and heavier, meaning the DC-130As could only carry one drone pylon under each wing. Each drone pylon was placed between the engines, replacing the auxiliary fuel tank on earlier models. When C-130E models were converted to drone carriers, they retained the underwing tanks and the drone pylons were installed outboard of the engines. This significantly increased the DC-130s' capability and operation time.
[edit] The drones
The Q-2C Firebee target drone was modified for the recon mission and designated the BQM-34A or 147A. Its size was increased to provide greater range and payload. For the low altitude mission, the wing span was increased to 15 feet (4.6 m) and later to 27 feet (8.2 m), but was most successful with the original 13 foot (4.0 m) wingspan. Wing spans of 27 and 33 feet (8.2 and 10.1 m) were used for the high altitude aircraft. The original 1700 pounds-force (7.6 kN) of thrust was increased to 1920 lbf (8.5 kN) and later to 2800 lbf (12.5 kN) for the special high altitude, long range drones. Some models were even equipped with wing-mounted fuel tanks to extend their range.
The drones had numerous navigation systems - including inertial, doppler, loran, etc. They were equipped with an analogue computer which controlled speed, altitude, heading, engine settings, sensors and recovery systems. That system turned all sensors on and off and directed all turns, climbs, dives (as well as the rate of each) and engine power settings. Depending upon their mission, the equipment also included:
- Rivet Bounder - a system to jam the SAM's guidance signal
- TWT - a traveling wave tube to give it the return of a U-2 or even larger aircraft
- CRL - a system to suppress contrails to reduce visual detection
- HIDE - a system to reduce the aircraft's radar reflectivity
- HEMP - a system to detect interception by enemy fighters and initiate evasive actions
- HATRAC - a system for high altitude flights to detect intercept by either fighters or SAMs and take evasive actions
Sensors included numerous cameras to satisfy the many different objectives of both low and high altitude sorties. The cameras may be fixed, turreted, or scanning horizon-to-horizon film cameras. Some provided fine detail of specific targets while others covered large areas. There were also TV cameras that could be zoomed and panned.
Numerous electronic receivers are also inplaced. They were designed to intercept communications of all sorts, radars, data links, etc. The intercepted data was then transmitted to other aircraft, ground sites or satellites. Some of the receivers could be tuned by an operator in another airplane or on the ground. The function of some receivers was strictly defensive. When they detected and identified a signal as a threat, they would trigger a jamming signal, dispense chaff and/or initiate defensive maneuvers.
For recovery, they have a recovery system and receivers that permitted overriding the program and flying it 'by hand'. The recovery sequence was triggered by the flight control computer at the preset position, unless overridden by the Drone Recovery Officer (DRO) in the control vehicle. Normally the drone was picked up by radar as it approached the recovery area and controlled by the DRO. Last minute course corrections were made as necessary and the recovery sequence triggered at the precise point to drop the drone on top of the waiting recovery helicopter. The on-board recovery system consisted of a servo that shut down the engine, deployed a drag chute (to cause the drone to nose over) and opened the main parachute at a preset altitude. The recovery helicopter then flew over the main chute engaging a reinforced catch chute with a set of trailing hooks attached to an internal winch. The drone was then winched up to just below the recovery helicopter and flown back to base. An alternative method of recovery allowed the drone to reach the ground under the main chute. On ground impact a sensor operated a charge that severed the chute risers allowing the drone to be recovered. This method had a higher likelihood of damage and was not preferred.
[edit] Results
The DC-130 program was eventually closed, as it was deemed too expensive to support. Launching a single drone required the maintenance and support for the DC-130, the drones, and the drone recovery helicopters (HH-3 and/or HH-53).
[edit] Specifications
- Primary function: control of unmanned aerial vehicles.
- Contractor: Lockheed Aeronautical Systems Company.
[edit] Crew / cost
- Crew: Air Force: 6 officers: pilot, co-pilot, navigator, remote control officer, and 2 launch control officers, and 2 enlisted: flight enginner and MCGS (microwave control guidance system) operator. eight Navy crew.
