Nite Panther was conceived as a derivative of the Advanced Research Projects Agency's (ARPA) Nite Gazelle Program using the U. S. Navy's QH-50 DASH - (Drone Anti Submarine Helicopter) System which was originally designed to provide destroyers with stand-off capabilities for the delivery of MK-44 torpedoes against submerged submarines.

    Nite Panther was a reconnaissance/observation system which provided a real time visual display day or night through the medium of a remotely controlled and commanded television equipped Model QH-50 helicopter and a Model M38A1, 1/4 Ton, 4x4 Truck Control Station, seen below right.

The system had the capability to perform spot search, specific area search, small area reconnaissance, target detection and identification, indirect fire adjustment and assist in establishing and maintaining perimeter defense security for both base camp areas and deployed unit locations.

The Model QH-50D is a stable sensor platform still in use today which has a degree of stability such as to minimize introduction of degradation or loss of resolution into the image returns being provided by the television sensor due to platform movement.

The Model M38A1 used was a standard jeep which had been adapted to carry a modified Target Control System AN/SRW-4B as the command link between the ground and the airborne vehicle in addition to start up equipment for the QH-50 and for receiving, monitoring, recording and subsequent playback of television information generated by the airborne vehicle. In addition, the jeep had been outfitted with a Special Support Telemetry System to monitor 38 data parameters and two synchronizing channels which were processed by the airborne telemetry system.

 

There were TWO separate JEEP installations; the one above which was ONLY a Command, Control with remote TV monitoring station and another installation which had "Start" AND Command and Control capability - That Installation was called the COMMAND-START JEEP and is seen as follows.

    Based on discussions with representatives from the Advanced Research Projects Agency of the Department of Defense, the Gyrodyne Company of America, Inc. on 7 March 1968 commenced implementation of the Nite Panther Program concept in response to an urgent operational requirement for the U. S. Marine Corps.

The subsequent sequence of events followed:

    The Advanced Research Project Agency's Nite Panther concept was a reconnaissance/observation system which provided for transmission of real time television information from an airborne platform to shipboard or mobile ground control stations. Such real time television information was obtained, day or night, from a remotely controlled TV system mounted aboard a Model QH-50 unmanned helicopter which was commanded from either the shipboard or jeep control station.

    In addition to the television system as a primary sensor, the QH-50 helicopter was equipped with a telemetry system (including distance measuring equipment (DME)), altitude measuring devices, and a laser range-finder. Two (2) auxiliary fuel tanks were also provided aboard the airborne vehicle to provide extended mission range capability over that normally available in the basic 52 gal. tank. Radar transponders for enhancement of surface radar return signals were provided as well as a still picture photographic camera.

THE AIRBORNE PLATFORM

Functionally, the QH-50 Nite Panther airborne platform provided for the following:

1. Observation of the ground using a television camera with either a daytime or nighttime capability, and transmission of the TV information back to the ship- board or jeep control station.

2. Reception of commands from the control station and operation of the TV camera (including associated lens or the IR illuminator), the laser range-finder, and the still photographic camera.

3. Measurement of aircraft status and transmission of information back to the control station.

4. Measurement of aircraft altitude and rate of climb (if implemented) and transmission of this information back to the control station.

5. Determination of slant range from the QH-50 vehicle to the ground point or area being observed by the TV camera and transmission of this information back to the control station.

JEEP Control Stations

   The Model M38A1 was a standard jeep which was adapted to carry command. telemetry, and television equipment with the necessary power supplies.

Functionally, this control station provides for the following:

1. Start up and pre-flight checkout of the QH-50 vehicle.

2. Command of the aircraft from takeoff to touch- down. Provision was made for takeover from and handover to either a shipboard control station or another Truck Control Station.

3.    Monitoring of aircraft status while in flight.

4.    Tracking of the aircraft and determination of its azimuth and slant range relative to the Truck Control Station.

5.    Receiving, monitoring, recording and playback of television information transmitted from the airborne station.

SHIPBOARD Control Station

     The shipboard control station was the basic DASH station modified and augmented to provide the expanded command, telemetry, and television capabilities of the Nite Panther system. In addition to those functions provided in the Truck Control Station, the shipboard control station provided complete support for the Nite Panther QH-50 vehicle.
 

Television System

   The television system was comprised of three stations, one airborne, one shipboard and one on the jeep. At the shipboard and jeep stations, it was possible to view a real time television picture of the area under observation by the TV camera aboard the QH-50 helicopter (seen at left). The television system operates on one RF center frequency in the microwave region and the video information (15 MHz baseband) was transmitted, at a 20-watt level, by FM techniques. Either a daylight high resolution monochrome TV camera or a low light level monochrome television camera could be mounted on the QH-50 helicopter. Remote control of either camera and associated lens was exercised from either the shipboard or the jeep control station through the command link. Equipment was provided in both control stations for receiving, monitoring, recording, and subsequent playback of television information generated by the airborne TV station.

   A Dynalens was provided for dynamic optical compensation of the effects of camera vibration on the TV picture. This lens could be mounted to either the daylight or low light level TV camera.

   The daylight TV camera utilized a 924-line raster and employs a remotely operated zoom lens which permitted closer viewing of objects of interest on the ground or viewing of a wide field for pilotage or observation purposes.

   The TV camera tilt angle could be commanded remotely from either the shipboard or the jeep control station. The tilt angle could be controlled from horizontal down to a 90 degree depression angle.

   The low light level TV camera utilized a 525-line raster and employed a fixed focal length lens. An infrared illumination light for use in conjunction with this camera to supplement natural nighttime illumination was eventually mounted on the QH-50 helicopter. This illumination source was then tilted remotely from the control station such that its axis remains parallel to that of the low light level TV camera.

Command System

    The command system employed two command links, a Target Control System, AN/SRW-4B, as the RF command link between the shipboard control station and the airborne station; and the Radio Transmitter AN/ARW-80 link between the jeep control station and the airborne station. Portions of the AN/SRW-4 were also employed in the jeep control station.

    Command of both the QH-50 helicopter itself and the sensor systems aboard was accomplished, in the case of each control station, through the respective command link.

    The command system was modified at the control station and in the airborne station to accommodate the increased requirements of the Nite Panther. In this modification the functions of: weapon arm, weapon release 1, weapon release 2, cable release, spare 1, spare 2, spare command word # 3, and command word # 6, of the basic DASH system were utilized or modified to provide for the following Nite Panther commands:

1. Daylight TV camera: tilt up-down, focus near-far, iris open-close, zoom in-out, RF and camera on-off.

2. Nighttime TV camera: tilt up-down, focus near-far, iris open-close, video gain low-high, RF and camera on-off, IR light on-off and tilt up-down.

3. Still photographic camera: on-off.

4. Laser rangefinder: on-off.

5. Extended altitude range: mode selection and control

6. Turn coordination: in-out.

7. Running lights: on-off.
    

Telemetry System

   The telemetry system consisted of three portions, one on the QH-50 helicopter, one at the shipboard control station and one at the jeep control station. This system provided the dual purpose of determining the position of the QH-50 helicopter; and of providing information to each control station pertaining to the operational status of the airborne station.

   The telemetry system employed PAM/FM/FM techniques and operated at microwave frequencies. The DME (Distance Measuring Equipment) was an integral portion of the telemetry system and permitted determination of the slant range of the QH-50 helicopter from each control station. The command transmitter in each control station was utilized to transmit the range tone from either the shipboard or jeep control station.

Laser Rangefinder

The laser rangefinder was provided to permit accurate determination of the slant range from the QH-50 helicopter to the observed point or area on the ground. The type employed was a pulsed beam laser which measured slant range every 12.5 seconds. The laser beam was tilted in synchronism with the TV camera in response to commands. Output of the rangefinder was transmitted via the telemetry link to the jeep control station. Ranges from 100 meters to 9,990 meters could be measured with the laser rangefinder.

Radar Transponders

   Both C- and X-band radar transponders were mounted aboard the airborne station. These devices facilitated radar tracking of the QH-50 helicopter through enhancement of surface radar return signals from the drone.
 

Altitude Measuring Devices

    In addition to the normal barometric altitude control employed aboard the QH-50 helicopter, a pressure altimeter and an altitude pressure transducer were provided. Provision was also made for mounting a rate of climb indicator adjacent to the pressure altimeter.

   The pressure altimeter and the rate of climb indicator could be monitored using the TV camera. A visual display at the shipboard or jeep control station, of the outputs of these two devices, was present on the TV monitor. The readout values of the altitude pressure transducer were transmitted to the jeep control station via the telemetry system on-coarse and fine altitude and rate of climb indicators.

Still Photographic Camera

   A KB-10A camera was mounted on the QH-50 helicopter. This pulse- operated still picture camera provides the added capability of photographing the area being observed by the daylight TV camera.

Extended Range Fuel System

   The extended range fuel system modification to the QH-50 helicopter provided approximately 80 gallons of additional fuel over and above the basic 52 gallons in the basic fuel tank, to be carried on a mission. Included in the system were two 40-gallon auxiliary tanks and their associated plumbing and check valves.

   The auxiliary tanks were of fiberglass construction and were mounted one on each side of the airframe. The exteriors of the auxiliary tanks, in addition to the basic 52 gallon fuel tank, were covered with a puncture sealing material.

Extended Altitude Range System

    The conventional altitude command system of the QH-50 helicopter was modified for Nite Panther to provide two modes of control which were selectively available as follows:

1.    Barometric Resynchronization mode in which the baro is resynchronized to zero output at a pressure corresponding to the actual altitude of the aircraft at the point of resynchronization. Altitude command control for climb to and descent from mission altitude was accomplished in increments of 600 feet maximum command range.

2.   Direct Collective mode in which the normal barometric altitude control system was bypassed and the collective pitch setting of the helicopter rotor blades was commanded directly by the controller at the control station.

   Either extended altitude range control mode could be remotely selected from the control station.
 

Turn Coordination Disabling System

     In order to prevent loss of visual orientation of the TV camera during turns, it was considered desirable to provide for the elimination of conventional banking of the QH-50 helicopter. To permit flat or uncoordinated turns, a means of disabling the turn coordination system was provided in the Nite Panther vehicle. The turn coordination system could be commanded in or out of the aircraft control system remotely from either the shipboard or jeep control station.

Lateral Trim Capability

   A lateral trim capability was introduced into the command system primarily to compensate for drift of the aircraft during the search and surveillance phases of a mission. This capability existed only in the cruise mode of aircraft control and could be utilized at both the shipboard and jeep control stations.

Collective Limiting Disabling

   To improve drone stability in higher gross weight configurations, the normal collective limiting system was disabled by removal of RPM crossfeed from the control system.

Protective Armor

   Protective armor was installed on the Nite Panther vehicle to reduce its vulnerability to small arms ground fire. Armor was placed forward, aft, and in lateral positions. Made of special lightweight material, this armor was positioned to maximize protection of vital portions of the QH-50 helicopter.

GYRODYNE Flight Testing of the NITE PANTHER Vehicles

   Gyrodyne, at the completion of the assembly of the Nite Panther vehicles, embarked on an accelerated ground and flight test program to verify that the installation was satisfactory. These tests were performed during the weeks of 25 March 1968, and 5 April 1968.

Among the three (3) vehicles DS-1700, DS-1701, and DS-1702, a total of 10 hours ground time and 2. 7 hours flight time were accumulated. Flight time was divided as follows:

These hours do not include the hours accumulated during production acceptance tests of the production configuration of QH-50 prior to incorporation of Nite Panther hardware. The following was accomplished during these flight tests:

1. Day TV systems was thoroughly checked on all three (3) vehicles.

2. Low light level TV system was checked on DS-1701.

3. Laser installation was checked on DS-1700.

4. Telemetry systems incorporated on the vehicles were actually utilized during the checkout of the drones. Further telemetry checks were made at San Clemente Island during weeks of 8 April 1968, and 15 April 1968.

5. Nite Panther flight speed envelope (0 to 50 knots) was examined at varying weights up to 2400 lbs.

6. Jeep station checks were made utilizing the Nite Panther vehicles. Transfer of control to the Jeep was thoroughly checked. Start capability was also checked.
 

Flights Conducted at San Clemente Prior to Deployment

* Please Note: The maximum design gross weight for the Nite Panther configuration was originally set at 2400 lbs. With the subsequent installation of the required Laser Rangefinder and other items, the vehicle gross weight was increased substantially, well beyond the 2450 lbs. As a result of this situation, a new permissible maximum gross weight of 2450 lb was established, the fuel load was reduced, and the time on station was decreased from the planned 2.0 hours.

NITE PANTHER - Epilogue

    While the NITE PANTHER program was rushed into production by ARPA as a tool to support the Marines in South Vietnam, it is not known how successful the program was or what missions the Marines flew with their aircraft. However, after the deployment to San Clemente island on April 7, 1968, the PANTHER team did not stay long. On 18 April 1968, the team deployed to U.S. Navy destroyers for operations in the Pacific and eventually ended up on the USS BLUE (DD-744). Of the three Nite Panther aircraft, each equipped to fulfill a different mission, all were lost on the following dates:

1. On 24 April 1968, Operating from the USS BLUE (DD-744) off Vietnam DS-1701 was lost.

2. On 27 April 1968, Operating from the USS BLUE (DD-744) off Vietnam DS-1702 was lost.

3. On 28 April 1968, Operating from a Western Pacific Ship, DS-1700 was lost.

Despite the losses, the ARPA technology that was developed from NITE PANTHER was eventually used in other programs although the Marine Corps never experimented with QH-50 VTOL-Unmanned Aerial Vehicles again.

DESCRIPTION OF DASH AIRBORNE AND SHIPBOARD SYSTEM

The DASH (Drone Anti-Submarine Helicopter) System consisted of a Model QH-50D vehicle (seen at right), which was a remotely controlled coaxial helicopter originally designed for ASW mission for delivery of two (2) MK-44 torpedoes while operating from a destroyer with AN/SRW-4 DASH Command and Control capability.

Command and Control

   Airborne

   The remote control for DASH consists of an airborne four-axis stabilization system and a receiver and decoder units of the digital pulse control monitor (PCM) data link. The four-axis stabilization system stabilizes the airborne vehicle in pitch, roll, yaw and altitude. Rotor rpm was maintained constant by the engine governor, a vertical gyro provides longitudinal (pitch) and lateral (roll) stability, and a directional gyro provides yaw (heading) stability. The altitude axis incorporates a barometric altitude sensing device. When a command was received via the ground portion of the data link, it has the effect of giving the particular axis commanded a new reference position.

   Shipboard

   The ship portion of the data link was the Target Control System, AN/ SRW-4. When operated from a destroyer, visual control of the drone was accomplished through the flight deck Transmitter Control. Track to the target, release of weapon (s) and return to within visual control was accomplished through the CIC (Combat Information Center) Transmitter Control.

   The CIC Transmitter Control was designed to provide air speed altitude and heading selection; this mode of operation was designated the "Cruise" mode, and was the only mode available in CIC. The Deck Transmitter Control incorporates the "Cruise" mode for control after take-off and prior to landing, plus a "Maneuver" mode for take-off and landing control. The “Maneuver mode allows accurate positioning of the drone through use of a maneuver stick. Heading and altitude were commanded through the same knobs in both "Cruise" and "Maneuver" modes and, in addition, heading may be changed at a constant rate by twisting the maneuver stick. In the "Cruise" mode, turn coordination was provided within the stabilization system so that lateral cyclic control was automatically applied when heading changes were commanded.

   General

    Nine channels were incorporated in the data link system for ON-OFF functions required for weapon arming and launching, engine stopping, releasing the landing cable, and other functions where required. A feature of the remote control system was the Memory function. It allowed the drone to operate for an indefinite period using the last received command data. The loss of a radio signal actuated the Carrier Loss function which placed the drone in a hover condition at the last commanded altitude and heading.

Airframe

   The basic Model QH-50 airframe consists of the following major components which was of simple functional design requiring minimum maintenance and allowing maximum access to the equipment:

   Fuselage - The lower casting of the transmission forms the main portion of the fuselage. Attached to the casting were the four supporting struts for the skid-type landing gear, the two lower aft fuselage tubes, and the bomb shackle and launcher mechanisms. The avionic equipment was mounted on a vertical aluminum honeycomb sandwich structure which was supported by four tubular members fitted into sockets on the transmission housings. The honeycomb panel and tubular members form the aft fuselage frame into which the fuel tank was nested for support.

   Transmission - The rotor transmission system consists of a two- stage gear reduction, two coaxial rotor drive shafts, an integral lubricating system, a generator drive and a rotary actuator drive. Power from the engine was transmitted to the rotors through the two-stage gear reduction, the second stage of which divides the torque to the two- counter-rotating co-axial rotor drive shafts. The generator and rotary actuator were driven by means of accessory drives in mesh with a single drive gear mounted on the lower rotor shaft.

   Rotor System - Two 20-foot diameter, 2-bladed, semi-rigid counter- rotating coaxial rotors comprise the rotor system. The blades were of fiberglass construction, incorporating linear taper in planform and thickness and negative twist. Rotor controls were operated by the Automatic Stabilization and Remote Control Equipment (ACSE). Control in pitch and roll was achieved through conventional cyclic control of the swash plates. Collective pitch control was obtained by conventional collective movement of the swash plates. Control in yaw was achieved by movable tip brakes connected to both the upper and lower rotor blade tips and provide positive directional control by creating unequal torque distribution in the rotor system. A left-turning moment results from the lower rotor tip brake deflection, and a right-turning moment results from, the upper rotor tip brake deflection. In the neutral condition, both sets of tip brakes were undeflected.

   Fuel Tank - The fuel tank of the Model QH-50D has a capacity of 52 gallons and was cylindrical in shape with its axis placed laterally on the drone. The fuel tank was positioned aft of the transmission and was secured by means of local cutouts and pads which permit it to be nested within the aft fuselage tubular framework. The cylindrical tank has dome-shaped ends and was reinforced by three circular baffles and one vertical baffle along the tank axis.

   Power Plant - The power plant for the QH-50D Drone was the Model T50-BO-12 Boeing Free Turbine, rated at 365 SHP at 6000 rpm, sea level standard conditions. The engine incorporates an electric starter. The engine was attached rigidly to the forward face of the transmission. The intake and gas producer section were forward and the power section aft, abutting the transmission. Engine exhaust was directed sidewise, outward and downward. The free turbine principle permits connecting the engine drive directly to the transmission without a clutch installation.

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