Gyrodyne QH-50 DASH

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QH-50 DD-692 1967.jpg
A QH-50 on board the destroyer USS Allen M. Sumner (DD-692) during a deployment to Vietnam between April and June 1967.
Role ASW drone
National origin United States
Manufacturer Gyrodyne Company of America
First flight 1959
Introduction 1963
Status In service as target tug
Primary users United States Navy
United States Army
Japanese Maritime Self-Defense Force
Produced 1962–1969
Number built 755
Developed from Gyrodyne RON Rotorcycle

The Gyrodyne QH-50 DASH (Drone Anti-Submarine Helicopter) is a small drone helicopter built by Gyrodyne Company of America for use as a long-range anti-submarine weapon on ships that would otherwise be too small to operate a full-sized helicopter. It remained in production until 1969. Several are still used today for various land-based roles.

Design and development[edit]

DASH was a major part of the United States Navy's Fleet Rehabilitation and Modernization (FRAM) program of the late 1950s. FRAM was started because the Soviet Union was building submarines faster than the US could build anti-submarine frigates. Instead of building frigates, the FRAM upgrade series allowed the US to rapidly update by converting older ships that were less useful in modern naval combat. The navy could upgrade the sonar on World War II-era destroyers but needed a stand-off weapon to attack at the perimeter of the sonar's range. The old destroyers had little room for add-ons such as a full flight deck. The original DASH concept was a light drone helicopter that could release a nuclear depth charge or torpedoes. The aircraft was considered expendable.

The manned Gyrodyne Rotorcycle program of the mid-1950s provided prototype work for the DASH, and ultimately the Rotorcycle was modified to produce the initial drone version, the DSN-1/QH-50A The DSN-1 was powered by a Porsche YO-95-6 72 hp piston engine and carried one Mark 43 homing torpedo. The next developmental version was the DSN-2/QH-50B that was powered by two Porsche YO-95-6 engines and also carried a single Mk 43. Serial production of the DASH began with the third version, the DSN-3/QH-50C, in which a 255 hp (190 kW) Boeing T50-4 turboshaft engine replaced the piston engine and the payload was increased to two Mark 44 torpedoes. A total of 378 QH-50Cs were produced before production ended in January 1966.

A single QH-50A, (DS-1006) was re-activated after contractor testing to verify the tilt-float landing gear. A long cylindrical float was added to each corner of the extended skid framework. Each float could rotate 90° from horizontal, oriented to straight ahead, and incorporated a pad at the end for landing on hard surfaces. For landing on water the floats were rotated to the vertical position and the helicopter settled until the floats were approximately 75% submerged.[1]


A QH-50C hovers over the destroyer USS Allen M. Sumner (DD-692) during a deployment to the Mediterranean Sea in 1969.

The DASH's control scheme had two controllers: one on the flight deck, and another in the combat information center. The flight-deck controller handled take-off and landing. The controller in the Combat Information Center (CIC) would fly DASH to the target's location and release weapons using semiautomated controls and radar. The CIC controller could not see the aircraft or its altitude and occasionally lost operational control or situational awareness. Late in the program, there were successful experiments to add a TV camera to the drone. These DASH SNOOPYs were also used as airborne spotters for naval gunfire.[2]

A tethered landing system was developed to land and take off in up to Force-6 seas. This system consisted of steel rails that were screwed to the flight deck and a cable system to pull the helicopter out of the hangar bay. The helicopter was attached to the steel rails so that it would not slide off the flight deck in heavy seas. This system was occasionally set up and used aboard ship, but never used in rough seas to launch a helicopter.

The DASH came about because Gyrodyne had worked with the United States Marine Corps to develop a small, experimental co-axial helicopter, the RON Rotorcycle, for use as a scouting platform. A co-axial helicopter has two contrarotating main rotors to control torque, unlike the more common main rotor/tail rotor found on most helicopters. Co-axial rotors put more power into lift, allowing shorter rotor blades. Both traits help a helicopter to be as small as possible. On the downside, the blades must be kept very far from each other to avoid colliding, since the blades flex as they rotate. This leads to increased complexity and decreased maneuverability.

For a drone, these trade-offs were fine. For the DASH role, the original marine version had a turboshaft engine for improved performance and the replacement of the seats and controls with a remote-control system and stowage for two Mark 44 torpedoes. In this form the DASH could be flown up to 22 miles (35 km) from the ship, giving a submarine no warning that it was under attack, at least until the torpedo entered the water.[3]

Since it was expendable, DASH used off-the-shelf industrial electronics with no back-ups. The controls were multi-channel analog FM. Over 80% of operational aircraft losses were traced to single-point failures of the electronics. A total of 10% of the losses were from pilot errors, and only 10% of the losses were from engine or airframe failures.

The DASH program was canceled in 1969 and withdrawn from service 1968–1973. DASHes proved unreliable in shipboard service, with over half of the US Navy's 746 drones lost at sea. This was possibly due to inadequate maintenance support, as other services had few difficulties with their DASHes.[4] Although low reliability was the official reason, the manufacturer pointed to the expenses of the Vietnam War, and the lack of need for antisubmarine capability in that war.

Modified DASH vehicles continued to operate for several more years in the Vietnam War. With attached television cameras, they were used as remote artillery spotters and organic reconnaissance by their ships.

Until May 2006, a small number of QH-50D DASH drones were operated by the United States Army at White Sands Missile Range, where they were used to tow targets and calibrate radars and electronic systems.[5]

The Japanese Maritime Self-Defense Force (JMSDF) operated a fleet of 20 QH-50 drones, for use on its Takatsuki-class and Minegumo-class destroyers. With the difficulty of maintaining DASH operations after the termination of the U.S. program, the drones and associated equipment were removed from JMSDF service in 1977.


A remote control QH-50 drone helicopter on display beside an M118 90 mm anti-aircraft gun at the Fort Polk Military Museum outdoor park
U.S. Navy designation for nine pre-production aircraft, redesignated QH-50A in 1962.
U.S. Navy designation for three pre-production aircraft, redesignated QH-50B in 1962.
U.S. Navy designation for 373 production aircraft, redesignated QH-50C in 1962.
DSN-1 redesignated in 1962, nine pre-production aircraft for evaluation, with a 72 hp (54 kW) Porsche flat-four piston engine.
DSN-2 redesignated in 1962, three pre-production aircraft powered by two 86 hp (64.5 kW) Porsche flat-four piston engines.
DSN-3 redesignated in 1962, production aircraft powered by a 300 shp (225 kW) Boeing T50-8A turboshaft engine, 373 built.
production aircraft with a larger 365 shp (272 kW) Boeing T50-12 turboshaft engine, fibreglass rotor blades and increased fuel capacity, 377 built.
There were 10 modified QH-50Ds manufactured (Serial number 150AO- 160AO).[citation needed] The "DM" 550shp was supplied by a modified version of the Boeing T50-12. These were used for military reconnaissance for the United States Army during the Vietnam War.
Three QH-50D aircraft modified with Allison T63-A-5A engines.
Proposed production version of YQH-50E, not built.
Proposed twin-engine version of QH-50F with larger fuselage and rotors, not built.


 United States

Surviving aircraft[edit]

Version Serial Location Notes
QH-50C DS-1045 Pima Air & Space Museum, Tucson, Arizona[6] The oldest existing QH-50
QH-50C DS-1176 Aviation Unmanned Vehicle Museum, Caddo Mills, Texas.[7] "Lucy" - the only surviving Peanuts character.
QH-50C DS-1190 American Helicopter Museum, West Chester, Pennsylvania.[8] Marked as DS‑1082. Moved from Museum of Flight, Seattle, Washington.
QH-50C DS-1199 USS Orleck (DD-886), Lake Charles, Louisiana[6] Moved from the USS Radford National Naval Museum, Newcomerstown, Ohio after it closed.
QH-50C DS-1221 Hawthorne Ordnance Museum, Hawthorne, Nevada[9]  
QH-50C DS-1235 Cradle of Aviation Museum, Garden City, New York[10]  
QH-50C DS-1261 Russell Military Museum, Russell, Illinois[11][12] Moved from the Museum of Aviation, Warner Robins, Georgia.[6]
QH-50C DS-1284 USS Joseph P. Kennedy (DD-850), Battleship Cove, Fall River, Massachusetts[6]  
QH-50C DS-1287 Naval Undersea Museum, Keyport, Washington Possibly stored[6]
QH-50C DS-1289 Smithsonian National Air and Space Museum, Steven F. Udvar-Hazy Center, Chantilly, Virginia Carries a special version of the Mk 57 nuclear bomb.[6]
QH-50C DS-1320 New England Air Museum, Windsor Locks, Connecticut,[13]  
QH-50C DS-1322 Military Heritage Collection of North Texas, Nevada, Texas[14]  
QH-50C DS-1347 USS Laffey (DD-724), Patriots Point, Mt. Pleasant, South Carolina[6] Marked as DS-1343. Moved from US Army Aviation Museum, Fort Rucker, Alabama
QH-50C DS-1355 Carolinas Aviation Museum, Charlotte, North Carolina[15]  
QH-50D DS-1482 The Helicopter Museum, Weston-super-Mare, North Somerset, England[16]
QH-50D DS-1543 USS Joseph P. Kennedy (DD-850), Battleship Cove, Fall River, Massachusetts Snoopy version. Actually DS-1543A, a fully operational replica built by the Gyrodyne Foundation.[6]
QH-50D DS-1570 White Sands Missile Range, New Mexico[17] US Army markings. There are probably several other airframes stored here.
QH-50D DS-1660 Aerospace Museum of California, Sacramento, California[6]  
QH-50D DS-1664 Estrella Warbirds Museum, Paso Robles, California[18]  
QH-50D DS-1679 Patuxent River Naval Air Museum, Lexington Park, Maryland[6]  
QH-50D DS-1709 Classic Rotors Museum, Ramona, California[19]  
QH-50D DS-1757 Penn State University Aeronautical Engineering School, Hammond building, Pennsylvania[20]  
QH-50D DS-1914 Hawthorne Ordnance Museum, Hawthorne, Nevada Fake serial but fully functional replica, built as a tribute to Gyrodyne's founder, and on loan from the Foundation.[6]
QH-50D DS-1991 Gyrodyne Helicopter Historical Foundation, Reno, Nevada[21][22] Fake serial but fully functional replica. Occasionally makes public appearances.
QH-50D J-19 Japan Maritime Self Defence Force (JMSDF) Kure Museum, Hiroshima, Japan[23]

Specifications (QH-50C)[edit]

A QH-50C DASH drone with two torpedoes on the Gearing-class destroyer USS Joseph P. Kennedy (DD-850)

Data from Jane's All The World's Aircraft 1969-70 [24]

General characteristics

  • Crew: none
  • Length: 12 ft 11 in (3.94 m)
  • Height: 9 ft 8.5 in (2.96 m)
  • Empty weight: 1,154 lb (523 kg)
  • Max takeoff weight: 2,285 lb (1,036 kg)
  • Fuel capacity: 35 US gal (29 imp gal; 130 L)
  • Powerplant: 1 × Boeing T50-BO-8A turboshaft, 300 shp (220 kW)
  • Main rotor diameter: 2 × 20 ft 0 in (6.10 m)


  • Maximum speed: 80 kn (92 mph, 148 km/h)
  • Cruise speed: 43 kn (50 mph, 80 km/h)
  • Range: 71 nmi (82 mi, 132 km)
  • Endurance: 1 hr
  • Service ceiling: 16,400 ft (5,000 m)
  • Rate of climb: 1,880 ft/min (9.6 m/s)


  • 2× Mk.44 or 1× Mk.46 torpedo

See also[edit]

Related lists



  1. ^ "The Model QH-50A", Gyrodyne Helicopter Historical Foundation. Retrieved: 22 May 2014
  2. ^ Peniston, Bradley. "Unmanned naval warfare: Retrospect and prospect". Archived 2013-12-24 at the Wayback Machine Armed Forces Journal (, 20 December 2013. Retrieved: 29 August 2019.
  3. ^ Apostolo 1984, p. 67.
  4. ^ Friedman 2004, pp. 280–283
  5. ^ "Gyrodyne Today". Gyrodyne Helicopters. 2006-05-09. Retrieved 2012-08-17.
  6. ^ a b c d e f g h i j k "Gyrodyne Foundation Supported Museums". Gyrodyne Helicopter Historical Foundation. Retrieved 10 August 2019.
  7. ^ "Drone History". Aviation Unmanned Vehicle Museum.
  8. ^ "Gyrodyne QH-50C (Drone) DSN 3 | American Helicopter Museum and Education Center". American Helicopter Museum.
  9. ^ "QH-50 DASH Weapon System". Archived from the original on 2022-02-26. Retrieved 11 August 2019 – via Facebook.
  10. ^ "Gyrodyne QH-50C at the Cradle of Aviation Museum". Cradle of Aviation.
  11. ^ "Gyrodyne QH-50C DASH at Russell Mllitary Museum". Rod Bearden's Aviation Photos. Retrieved 9 August 2019.
  12. ^ "Russell Military Museum Exhibits". Russell Military Museum. Retrieved 12 August 2019.
  13. ^ "Gyrodyne XRON-1 'Rotorcycle'." New England Air Museum. Retrieved: August 4, 2013.
  14. ^ "Home". Military Heritage Collection North Texas.
  15. ^ "Carolinas Aviation Museum – Let Your Imagination Take Flight". Carolinas Aviation Museum.
  16. ^ "Arrival of Gyrodyne QH-50D DASH". Friends of The Helicopter Museum. Retrieved 10 August 2019.
  17. ^ "White Sands Missile Base Museum." White Sands Missile Range Museum
  18. ^ "Gyrodyne QH-50D DASH". Estrella Warbirds Museum. Retrieved 11 August 2019.
  19. ^ "Gyrodyne QH-50C DASH at Classic Rotors Museum". Rod Bearden's Aviation Photos. Retrieved 9 August 2019.
  20. ^ "The Incredible Story of the QH-50 DASH" (PDF). Penn State University Aeronautical Engineering School. Retrieved 11 August 2019.
  21. ^ "QH-50 DASH Weapon System". Archived from the original on 2022-02-26. Retrieved 12 August 2019 – via Facebook.
  22. ^ "QH-50 DASH Weapon System". Retrieved 12 August 2019 – via Facebook.
  23. ^ "Submarine Activities: Threats to Submarines". JMSDF Kure Museum. Retrieved 12 August 2019.
  24. ^ Taylor 1969, p. 519.


  • Apostolo, Giorgio. The Illustrated Encyclopedia of Helicopters. New York: Bonanza Books, 1984. ISBN 978-0-51743-935-7.
  • Friedman, Norman (2004). US Destroyers: An Illustrated Design History (Revised Edition). Annapolis: Naval Institute Press. ISBN 1-55750-442-3..
  • Polmar, Norman (1993). "Question 1/91: USN DASH Helicopters". Warship International. XXX (3): 317. ISSN 0043-0374.
  • Taylor, John W.R. Jane's All The World's Aircraft 1969–70. London: Jane's Yearbooks, 1969.
  • Wetherhorn, Areyh (1992). "Question 1/91". Warship International. XXIX (3): 310. ISSN 0043-0374.

External links[edit]