The Model QH-50D

    Building upon the fleet experience of the QH-50C, and recognizing several deficiencies of the C model, the Navy requested and ordered the improved D model variant of the QH-50 on April 6, 1964. On August 20, 1965, the Navy authorized Gyrodyne to begin installing fiberglass rotor blades on the D model and to retrofit the existing C models with the lower maintenance fiberglass blades.

    Through June 1966, Gyrodyne received orders for the Navy's purchase of 377 D model DASH drones, beginning with serial number DS-1382 (1 of 4 modified C models). By the time production ended on August 29, 1969, some 377 "tail-less" QH-50D aircraft had been produced at Gyrodyne's Long Island, New York manufacturing facility for the U.S. Navy with an additional 16 being delivered to the JMSDF and two manufactured for Gyrodyne itself; resulting in a total of 395 D models produced.

    While the ASW dedicated QH-50D was being built and fielded by 1966, the ASW mission it flew from U.S. Naval destroyers was beginning to be seen as being largely unnecessary because the SQS-26 detection sonar system needed to take advantage of the DASH range, that had been part of the FRAM program, was still not yet available.
    When the DASH operational range requirement was established to be a minimum 30 miles, it was intended that the DASH range equal the effective range of the intended SQS-26 sonar, then under development. This sonar was scheduled for operational evaluation in 1962 to determine its acceptability for service use and was programmed for installation as a long-range detection system aboard anti-submarine warfare destroyers. The availability of the sonar failed to materialize as planned due to technical problems and was not approved for service use until November 1968; a full 6 year delay. Further, the Navy faced a hard economic choice: While the 1960 initiated FRAM I program was only designed to extend destroyer life by 8 years (FRAM II for 5 years),  The availability of the Sonar with increased detection range occurred at the time the destroyers had reached their operational lifetime limit. Should the advanced Sonar be installed in ships scheduled for decommissioning?

    During 1966, destroyers were operating with sonars that did not regularly obtain ranges of more than 10,000 yards. Accordingly, while having an operational radius of 30 nautical miles (about 60,000 yards) had been established as a requirement for and had actually been achieved during tests of the DASH drones, the maximum weapon delivery requirement of the drones was only the effective sonar range of the launching ship! 

    This factor led to eliminating the need for further DASH procurement and removing DASH from certain ships in the fleet. 
    Because of the then effective sonar range detection issue, the Department of Defense concluded that it did not make economic sense to upgrade the sonar of FRAM I ships to utilize the DASH range. Accordingly, on FRAM I destroyers, ASROC and DASH became redundant ASW systems. 

    In light of the lack of the ability to utilize the range of the DASH QH-50D, the Secretary of Defense decided against further procurement of the drone helicopters and concluded that existing QH-50D drones should be used ONLY on FRAM II destroyers and destroyer escorts of the 1006 and 1021 classes; which did not have ASROC. It was believed that, by using the existing inventory of these DASH drones on only the FRAM II destroyers and the aforementioned destroyer escorts, there would be a sufficient inventory of QH-50D drones on hand to meet the Navy's needs for the foreseeable future and that there would be no need for further procurement of DASH drones.

    Subsequently, in December 1967, the Chief of Naval Operations directed the removal of DASH drones from FRAM I destroyers. With QH-50D drone inventory now in excess of the ASW mission requirement, the Navy, in cooperation with the Advanced Research Projects Agency (now called DARPA) began modifying many QH-50D drones in order to expand its role and mission; missions that had been the exclusive realm of manned aircraft, like the aircraft below-right, to better fit the needs to the Navy's then current mission. 

The QH-50D Expands the Mission envelope beyond simple ASW

Under NAVY/ARPA Program DESJEZ, a Navy QH-50D, S/N DS-1751,(seen right) launches from the destroyer, USS MOALE (DD-693) on an ASW mission at sea on July 2, 1969.

In program F0251 "DESJEZ", the QH-50D vehicle had the capability of flying at 4700 ft altitude to a distant sonar contact then dropping to sea level for launching of its own eight sono-buoy sensors, loiter while relaying contact information back to the destroyer and then after detection of the submarine target, it could then drop its MK-44 torpedo for target destruction, all at a 50 mile distance from the launching destroyer. DESJEZ aircraft had three long range fuel tanks for the extended range operations up 4 hours in length. The QH-50D no longer was solely reliant on ship's sonar. With this capability, the QH-50D DESJEZ became a hunter-killer platform and was not limited to the ships sonar detection range.

    The improvements made over the preceding C model made the expansion of payload capabilities for the D possible and thus, the QH-50D's mission was greatly expanded.

The major improvements found on the D model were:


Higher horsepower Boeing Free Turbine engine, model T50-BO-12, which added additional 65 shp. 


BO-12 engine also was 84 lbs lighter than the C model's BO-8A (Boeing model 502-10VC).


Lighter weight Fiberglass rotor blades replaced wooden blades; increasing payload by 52 lbs.


Rotor blades given de-icing capabilities (internal heater mat) and all-weather capability.


Improved flotation package.


Aft Tail assembly of the C model deleted on the D model; increased payload by 100 lbs (P/N Y63-315460-1 and -16)


Increased basic fuel capacity from 35 to 52 gals.


The relocation of sensors (gyros and altitude control) to fuselage support housing.


The weapon mounting lug area of the fuselage support housing was redesigned to accommodate a "special weapon".


A clear approach was made for the Weaponmobile to the aft end of the drone therefore greatly increasing ease of weapon loading.


The transmission oil capacity was increased and the oil pump design was changed to make it an integral unit allowing it to be removed for bench testing.

    Taking advantage of the increased payload capabilities of the D model, ARPA had numerous programs in which they extensively "weaponized" the QH-50D. ARPA program "Nite Gazelle" made the QH-50D at left an anti-personnel weapons platform by the installation of two XM-18 Bomblet dispensers and two M5 Turrets- one turret carried an XM129 Grenade Launcher and the other a high resolution TV camera. Both turrets were slaved together so the drone controller could track what he was shooting at. Each Bomblet dispenser consisted of six tubes; each tube held 19 bomblets.

  On the right, two separate programs that were merged together further illustrates ARPA's weaponization of the QH-50D; program ATTACK DRONE and GUN SHIP:

1.    U.S. Navy QH-50D ATTACK DRONE program, s/n DS-1685 (background-right) is equipped with a telemetry package, Cohu real-time-down linked TV Camera mounted on a calibrated tilt mount with an ordnance load of two MK-81 bombs (250 lbs each).

2.    U.S. Navy QH-50D GUN SHIP program, s/n DS-1679 (foreground-right) is equipped with a daylight Cohu TV Camera that is bore sighted to the calibrated tilt mounted General Electric GAU-2B-A Minigun. The camera is used for target acquisition, aiming and damage evaluation. A close up of the General Electric GAU-2B-A Minigun, is seen at left.

The Navy’s development of GUN SHIP and ATTACK DRONE was based on the teaming of the two vehicles with GUN SHIP as lead aircraft to clear a low level flight path to the target point where ATTACK DRONE could release its’ ordnance load on a time critical target; all with zero risk to the operating pilot-some 40 miles out at sea. This system was for deployment to S. Vietnam.




What about Surveillance?

    Reconnaissance, Surveillance and Target acquisition (RSTA) had actually been the QH-50D's first foray into a non-ASW application. Simply equipped with a real-time TV camera and flying from the same destroyer platforms it used for its ASW role, NAVY program SNOOPY, started in January 1965. The SNOOPY program had a simple goal: Give the Destroyer Commander an "over-the-horizon situational awareness" in order to more accurately target the Destroyer's 5" guns and provide immediate gunnery correction. Soon however, the QH-50D was providing gunnery data for the battleship, USS New Jersey.

    ARPA Program NITE PANTHER sought to expand SNOOPY by providing not only real-time TV down-link, but 3 hour loiter capability with a 50 mile operating range from the launching destroyer: Navy QH-50D, S/N DS-1735 (seen left), equipped with 3 separate fuel tanks for long range, aims its low light video camera at the photographer. The aircraft’s range could have been much greater, but the range was limited due to the tracking radar in use in the 1970’s by the launching Destroyers which used radar to track the Vehicle to and from its target.

    While ARPA and the Navy discovered that using the QH-50D as a multi-weapons platform was an easy extension of its ASW role, the idea of using the QH-50D as a Target Acquisition vehicle in "enemy active" regions was a novel use of its unmanned aircraft nature and allowed for "high threat environment" missions without the concern for possible loss of the pilot.

    As seen at left, is a ARPA program, Nite Gazelle QH-50D equipped with an MTI AN/PPS-5 Radar System. With the system being attached with a Two-Axis tracking mount, this QH-50D transmitted its Airborne Warning Radar information through the telemetry system to ground display for target identification. In this use, the UAV provided over-the-horizon, real-time radar coverage for the launching destroyer. In this role, the QH-50D became the first and ONLY UAV to be ever used in a AWACS application!

    Given the success of the SNOOPY, Nite Panther and Nite Gazelle QH-50D programs, the question of being able to more effectively destroy a target, after enemy target identification and classification had occurred. ARPA responded with an extension of Nite Gazelle in which a Laser designator was utilized:
    QH-50D, s/n DS-1715 (seen left), was a target designator intended to provide illuminated targets for waiting fixed-wing fighter-bomber aircraft . DS-1715 would use its day or night TV camera to locate the target for the off-shore controller. Then upon authentication of the enemy target, the laser unit would be activated into designating the target allowing for waiting fighter-bombers to drop laser-guided munitions using the QH-50’s laser beam for tracking to the target. The Laser/Camera unit was placed on a tracking mount. Later, this QH-50D was armed with the LARS rocket system so that it could also fire at its own acquired targets.


Derivatives of Uses for the QH-50D DASH VTOL-UAV

Project Name Sponsor Description
DESJEZ U.S. Navy Sonobuoy Dispensing, ASW Detection and Target destruction. Program was to also show defense of aircraft carriers from ship to ship missiles by acting as a decoy.
SNOOPY U.S. Navy Surveillance with real-time TV for Gun spotting for U.S. Surface Ships off Vietnam
MIDGET U.S. Navy Evacuation or Rescue (personnel)
DAMPS U.S. Navy-Dam Neck Facility Electronic Countermeasures
SEEK LAUNCHER ARPA/U.S. Air Force Surveillance- Base Perimeter Defense using MTI radar and low-light TV 
BLOW LOW DIA / ARPA / U.S. Navy Surveillance (Day or Night) Sensor payload-classified
ARMY ARMED DRONE ARPA / U.S. Army Ordnance Delivery / TV Surveillance (used XM-129 Grenade Launcher and XM-25 Bomblet dispensers)
NITE PANTHER ARPA Surveillance and Artillery Spotting by the use of Radar. day and night TV, and other sensors with tracking capability for moving targets.
NITE GAZELLE ARPA Nite Panther with Ordnance delivery (precision bombing, SAWS Ammo, rockets and missiles) capability on stationary and moving targets: 
GRANDVIEW ARPA Nite Gazelle operating through a Relay Data Link to extended ranges
CARGO GYRODYNE Vertical replenishment at Sea (VERTREP) and to high risk areas
SMOKE LAYING GYRODYNE Laying of Smoke to provide protective screening
MASSTER ARPA / U.S. ARMY Validation testing for Unmanned Aerial Surveillance System concept at Ft. Hood Texas; MTI radar and Low light TV as sensors.


Although great strides were made using the multi-platform capabilities of the QH-50D UAV in its use as a weapons delivery and RSTA platform, DARPA ceased using the aircraft in 1974 due to the draw down in defense expenditures associated with the end of the Vietnam war. With the DASH program having been officially cancelled in November 1970, further strategic and tactical use for the QH-50D ended and the remaining 388 QH-50C and D model drones were transferred to Naval Air Warfare Center-China Lake and U.S. Army's PEO STRI - White Sands Missile Range. There, the unmanned air vehicle that was developed to extend a pilots reach without increasing his risk, was unceremoniously used as a "Target" for "real-kill" missile and anti-helicopter development; over 350 aircraft were simply blown out of the sky before the military began to rethink this policy.

    In 1986, The U.S. Navy was running out of QH-50s at an alarming rate because missiles were becoming much better. Believing that the 1965 fly-away cost of $154,000 per aircraft had remained the same, the Navy issued an RFQ for 21 QH-50D drones to be built by Gyrodyne and was stunned to learn that the 1986 cost, using a modern Allison 250-C20S engine (Boeing ceased their engine manufacturing in April 1968 to devote all their resources to the new 747 airliner program) was approximately $ 2.2 million per aircraft. The Navy then began having their existing aircraft "tow" targets to prevent the QH-50s from being shot down and this target-towing continued long after NAWC-China Lake lost their QH-50 program and aircraft to U.S. Army's Program Executive Office for Simulation, Training, and Instrumentation (PEO-STRI) in 1995.


    Today, there about 26 QH-50D UAVs that are still in use at U.S. ARMY PEO-STRI's TMO. 
Gyrodyne Helicopter Historical Foundation is the only civilian entity that owns one
(see our museum supported page to see it at the Hawthorne Ordnance Museum)

    As the QH-50D remains an active asset of the Department of Defense, we supply the following data for those using the aircraft for their payload demonstrations.


Take-Off Loading Conditions- Full Reg. Fuel (no aux fuel)

First Flight of QH-50D was on April 9, 1965



The Model QH-50D Drone is a remotely controlled rotary-wing ASW weapon carrier designed to deliver alternate weapon loads of 920 lb or 1140 lb. Combat radius of the-drone is about 40 nautical miles with 4 hour loiter, depending on loading condition, at a cruising speed of 80 knots. The drone incorporates two two-bladed counter-rotating coaxial rotors of the semi-rigid (see-saw) type.
    The blades are of fiberglass construction, incorporating linear taper in planform and thickness and negative twist. The machine is completely controllable through the rotors. Rotor controls are operated by the automatic stabilization and remote control equipment (ACSE).
    Control in pitch and roll is obtained through conventional cyclic control of the swash plates. Control in yaw is 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. 
    The power plant is the 365 shp T50-BO-12 Boeing Free-Turbine engine permitting connecting the engine drive directly to the transmission without a clutch installation.

Engine (1) T50-BO-12 Empty 1035 Lbs
Manufacturer Boeing Airplane Co. Normal Gross I 2330 Lbs
Type Gas Turbine Normal Gross II 2550 Lbs
Turbine is single axial and centrifugal stage with two reverse-flow can-type combustors.    



  SHP RPM ALT No. of Tanks Gallon Cap. Location
Military 365 6000 SSL One 52.0 gals Aft of Trans.
  Grade of Fuel: JP-5


AN/ARW-78 (1 each) Radio Rec. Set Capacity: 3.0 gallons
AN/ASW-20 (1 each) Automatic Flight Control Set Specification: MIL-L-7808C
  Fuel & Oil weight  375 LBS.
  Empty weight  1035 LBS.
 920 LBS.
 1140 LBS.
MAX Rotor RPM 610
Ceiling: Service 16,000 ft.
Hover: (OGE) 6500 ft.
Hover: (IGE) 11,500 ft 
Vertical Rate of Climb at Sea Level 1180 fpm
Maximum rate of climb at Sea Level 1880 fpm
  Max. Speed/alt. 80 knots/S.L.

QH-50D Drone General Assembly Diagram

1. Tip Brakes 7. Airborne Generator 13. Antenna
2. Upper rotor assembly 8. Transmission housing 14. MK-44 Homing Torpedo
3. Static pressure pick-up 9. Fuselage frame and    
    transmission support housing
15. Engine
4. Rotating controls 10. AFC set components 16. Servo actuator
5. Lower rotor assembly 11. Fuel Tank 17. Non-rotating controls

6. Bell Housing

12. Landing Gear  

Serial Number History

QH-50D Drone

Serial Numbers

Number Produced

Manufacture Date


DS-1382 (seen above) 1 January 2, 1966 Built under contract NOw 64(A)-0158-i, DS-1382 was converted from a C model to a D after three other C models had been converted and tested as YQH-50D's.
DS-1383 through DS-1385 3

January 2 to 20, 1966

Upon acceptance of DS-1382, the other converted QH-50C's that had been converted into D's lost the YQH-50D designation and were accepted by the Navy as well.
DS-1386 through DS-1572 186

January 20, 1966 through July 1967 

The initial batch of original QH-50Ds, these aircraft were quickly deployed to the fleet so that the less reliable C models could be retired and stored. Because of this swapping, the C models became available at stateside for weapons developments and were used as targets by NAWC-China Lake sooner. This is why so few C models remain today, other than in museums.
JMSDF Aircraft J-1 through J-16 16

 November 1966 through January 1967

As a follow-on production to the 3 QH-50C's and single QH-50D provided by the U.S. Navy, The Japanese Maritime Self-Defense Force (JMSDF) ordered 16 additional aircraft for their DASH program. During the program, which ended in 1976, the Japanese attained a MTBF of over 500 hrs. During the program they lost only three reported aircraft. What happened to the remaining QH-50Ds is not known.
DS-1573 through DS-1758 187

July 1967 through August 29, 1969

DS-1758 marked the end of "Official" Navy production. DS-1758 did not survive having been used as a aerial target by the Navy, but DS-1757 did (second to last) and is awaiting disposition at White Sands Missile Range-U.S. Army PEO-STRI's TMO.
PJP-1 through PJP-2 2

September 1 through 7, 1969

Manufactured before the assembly line was shut down, these two aircraft were ordered by the President of Gyrodyne, Mr. Peter James Papadakos. Mr. Papadakos felt that these two aircraft would be needed in the future and they were- 18 years later, in 1987 they were shipped to Germany where the Dornier company used them to demonstrate a new way to use the QH-50 Helicopter. They both are currently still in Germany.




Helicopter Historical Foundation
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GHHF is dedicated to the advancement of the education and preservation of the history of the Ships, the Men and the Company that built, operated and flew the U.S. Navy's QH-50 Drone Anti-Submarine Helicopter (DASH) System and to the preservation of the history of the U.S. Army's past use of DASH.
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