Westland remotely-piloted helicopters (RPH)

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Westland WG.25 (WR-05) "Mote"
During 1968 the Future Project team began its assessment of an unmanned rotary wing battlefield observation system, a role assigned at that time to manned helicopters and the primary combat support role envisaged for the planned “Gazelle” AH.1. Austin’s Future Projects team had elected to consider how airborne battlefield surveillance might best be assured in a non-permissive anti-air environment: their conclusion was that small, semi-disposable, unmanned aircraft possessing an inherently low signature was the solution of choice.

The outcome was project WG.25, a 200 kg turbine powered co-axial rotorcraft having low optical and noise signatures. Later refinements would add low radar cross section by virtue of a smooth plan-symmetric shape and a novel control system having no preferred direction of flight such that the data link antenna could be pointed using yaw control.

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Westland WR-06 “Wisp” (MoD project CONGA)
Westland WR-07 "Wideye" (MoD project SUPERVISOR)
Westland WR-08

From around 1971, MoD sponsorship for studies of the concept of an unmanned rotary wing target acquisition system included contracts with WHL and Canadair covering airframe aspects. The Westland study was to derive a somewhat smaller air vehicle than envisaged by the WG.25 outcome as the required endurance and the likely mass of the electro-optic payload was further refined. Air vehicle stabilisation and navigation to and from the on-task area was to be fully automated. Following completion of this study activity a sub-scale model was built and flown to demonstrate the resulting novel control requirement.

Later, contracts were received for a demonstrator (WR-06 “Wisp”) and a full scale quasi-operational demonstrator (WR-07 “Wideye”) under the MoD project names of CONGA and SUPERVISOR respectively. Under cover of these programmes an extensive investigation of radar cross section and engine exhaust thermal signature management was launched. The plan-symmetric smooth external shapes were augmented using radar absorbent materials (RAM) manufactured as semi-structural items by Plessey (Towcester) and trials were executed in the UK Radar Cross Section (RCS) measurement facility (second and third image below).

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As a direct result, further investigations of the effects of airframe shape and rotor blade construction were undertaken and the WR-08 configuration with a conical plan-symmetric airframe was both wind tunnel and radar range tested with mixed success: radar cross section was markedly reduced without reliance on the use of RAM but unstable aerodynamic behaviour was witnessed in the Westland wind tunnel.
No ready solution could be found to the poor aerodynamic behaviour and so the planned production of SUPERVISOR system to meet GSR 3494 was to retain an air vehicle having a smooth barrel shaped fuselage with structural RAM skin panels and retractable undercarriage. Taken together these measures were determined to achieve a level of radar cross section judged by Royal Signals & Radar Establishment/Royal Armament Research & Development Establishment (RSRE/RARDE) as commensurate with appropriate levels of battlefield survivability.

Source: Westland and the Attack Helicopter – from Lynx to Apache, by Dr R V Smith, FRAeS; J P Graham, FRAeS (2020).
 
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Westland PHOENIX proposal
Following the termination of the SUPERVISOR programme in late 1979 the Army OR staffs remained true to the concept of unmanned aerial surveillance and launched a revised and simplified operational requirement as GST 3846 under the programme title “PHOENIX”. The OR staffs expressed a desire that all parts of the system should exhibit low signatures, but values were not prescribed.

Industry was invited to comment and offer system solutions. Along with BAe, Ferranti and Marconi, Westland was selected to complete funded PD activities with the intent that a down select to two would then lead to a funded “fly-off”. The Westland bid, managed and submitted by British Hovercraft Corporation (BHC), included a low signature air vehicle, being small in size, having an extreme focus on shaping to minimise RCS and fully integrated, shielded and silenced, hot exhaust management.

Wind tunnel testing proved that the shape chosen was stable and exhibited low drag; radar range testing demonstrated that the targets set by the SUPERVISOR programme had been met with some margin. The Westland proposal was not selected for the fly-off programme which was eventually won by GEC Marconi using a Flight Refuelling fixed wing air vehicle having no obvious attention to signature reduction.

The Westland team were re-assigned in March 1983 to other programmes although would be re-formed briefly in 1990 to support the delivery of flight ready hardware to Martin Marietta in California for use in demonstration tests of the proposed Battalion Targeting System (BTS). The concept developed by Martin Marietta was for a low signature, tethered, air vehicle mounting a radar sensor. The helicopter rotor was to be co-axial and mounted on a plan symmetric conical fuselage: Westland wind tunnel trials with this low radar cross section configuration pre-dated the BTS by more than 20 years!
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The RPH experience with the use of shaping to minimise RCS was quickly absorbed into the Project Office analysis of options for a future combat rotorcraft and contributed to work already completed on novel cockpit geometry for optical glint suppression. Awareness of these issues also influenced Westland’s proposal for a lozenge-shaped fuselage cross-section for the NH90 helicopter, made by Smith as part of the NH90 Configuration Team during the Feasibility and Pre-Definition Study (FPDS) Phase (prior to the UK’s withdrawal from the programme).
Source: Westland and the Attack Helicopter – from Lynx to Apache, by Dr R V Smith, FRAeS; J P Graham, FRAeS (2020).
 
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Apophenia suggested earlier that the WG.25 program may not relate to the "Mote" only, and apparently he was right:
Further research and development continued for a while and one final WG-25 variant was proposed in 1980 as the SHARPEYE. This featured a redesigned and more 'stealthy' aerodynamic body, built around the Wideye mechanical components. The entire WG-25 project was finally abandoned in 1983 after only a wind tunnel mock up of the Sharpeye was built.

All four WG-25 variants are on display including the only Mote built, the first of the Wisps, a typical Wideye and the full scale Sharpeye.
Incidentally, this source adds another RPH to the WG-25 program: the Sharpeye, which happened to be the WR-09.

Source: https://helimuseum.com/heli.php?ident=mote
(note that the page made a typo, spelling "WG" as "W6" in places)
 
Some complementary info...

The story of Westland Helicopters vertical take off and landing UAV (VTUAV) program began around 1967-68. A small team was set up at that time to see what a future battlefield surveillance / surveillance / observation vehicle might look like. It soon concluded that a small VTUAV was the way to go; piloted helicopters, however small and agile, were just too vulnerable. The Ministry of Defence (MoD) was quite intrigued by the idea. It issued a preliminary specification in 1971.

Unwilling to wait until the purpose-built TV camera was ready, Westland Helicopters designed and built, over a period of eight or so months, a proof of concept prototype fitted with numerous off the shelf aeromodelling components, including, it seemed, its two counter-rotating rotors and two piston engines. This Westland WR-05 Mote made its first flight (tethered or free) in June or July 1975. It worked well enough, as a proof of concept prototype without any useful load, but the addition of some sort of gyro increased the weight, which greatly reduced its flying abilities.

Even so, the MoD was so impressed that it put up money to develop a larger design that would be closer to an operational daylight-only VTUAV it might use in Northern Ireland. The first of three WR-06 Wisps made its first flight in December 1976. Within a year, the British military and / or Westland Helicopters concluded that the payload of the new VTUAV was too small. A production version known as the Vista (Visual intelligence, surveillance and target acquisition) therefore did not proceed beyond the design stage.

Designed in 1975, the Westland Pupil was a more powerful VTUAV which was to be fitted with two counter-rotating rotor and a single model aircraft piston engine, not to mention a black and white television camera. Given that much of the research work it was to carry had been done with the Wisps, the Pupil project was abandoned in 1977.

Westland Helicopters kept at it though and new design, based on the Pupil, the WR-07 Wideye, to fulfil a new British Army program, the Medium Range Unmanned Aircraft Surveillance and Target Acquisition System, a program later renamed Supervisor. Originally designed for use with a small turboshaft engine, that battlefield reconnaissance / surveillance VTUAV was eventually powered by a pair of piston engines. A prototype flew for the first time in August 1978. Westland Helicopters received a contract to build three or four more Wideyes but control of that overweight and oversized VTUAV was still problematic when the program was cancelled, in December 1979. It looks as if only one Wideye was actually built.

The company later developed a stealthy VTUAV based on its earlier work. This WR-09 Sharpeye was abandoned, in the early to mid ’80s, before an actual prototype was built. That said, a full scale wind tunnel model of that VTUAV was made. It might, I repeat might, be the vehicle in a photo above, the one which carries the serial ZS782.

Mind you, Westland Helicopters also took part in a MoD UAV competition around that time. Its thoroughly re-redesigned WR-10 proposal was successful during the first round of the competition but was not chosen to take part in flight trials. No prototype was actually built.

In 1990, Martin Marietta approached the company see if it was interested in jointly developing a new VTUAV. A Wideye was duly assembled using spare parts and shipped to California. It was test flown in 1991 but no further development ensued.

In the late 1970s or early 1980, Westland Helicopters’ chief project engineer for UAVs joined a small British company, M.L. Aviation. The MoD remained interested in acquiring a VTUAV similar to the Wideye but did not wish to help the new project team too much. Design of a VTUAV with a pair of contra-rotating rotors powered by two piston engines began in early 1981. The first Sprite (Surveillance Patrol Reconnaissance Intelligence Target designation Electronic warfare) was flight tested in 1983.

In 1988, a Sprite was tested on a rolling platform used to simulate the deck of a ship in heavy seas. The U.S. Navy was sufficiently intrigued to organize sea trials. A Sprite thus flew off the aft deck of a U.S. Coast Guard cutter / patrol vessel, in the spring of 1989. Better yet, M.L. Aviation received a seemingly firm order from the Swedish army for 130 Sprites. Sadly, the company went into liquidation after delivering a couple of VTUAVs. Even though interest seemingly remained high within the MoD and in foreign countries, no further production took place. All in all, a dozen or so Sprites were apparently built.

As was mentioned in another series of messages, with its numerous ups and downs, the quarter century story of the Westland Helicopters and M.L. Aviation VTUAVs oddly resembles the 35-year saga of the Canadair and Bombardier VTUAV projects (CL-227, CL-227 Sentinel, CL-327 Guardian).
 
Note: The RAeS Paper Westland & the Attack Helicopter from Lynx to Apache was jointly written by myself and Jeremy Graham (just as Westland Aircraft & Rotorcraft: Secret Projects & Cutting Edge Technology is jointly written by Jeremy Graham and myself. He and I worked on both RPH and Attack Helicopter projects and have cooperated in writing both these works. Credit both authors, please.
 
Note: The RAeS Paper Westland & the Attack Helicopter from Lynx to Apache was jointly written by myself and Jeremy Graham (just as Westland Aircraft & Rotorcraft: Secret Projects & Cutting Edge Technology is jointly written by Jeremy Graham and myself. He and I worked on both RPH and Attack Helicopter projects and have cooperated in writing both these works. Credit both authors, please.
Sorry. My mistake. I will try and fix it everywhere I made it. Thanks for your highly valuable work!
 
No problem - I'm not being stuffy, but Jeremy deserves significant credit on the book, not least because of the work he has done in both the company and national archives. We also both worked on NH90 and, while I departed to work for BAe / BAE Systems, Jeremy spent his entire career at Westland and currently co-chairs the local RAeS Branch, and looks after the Leonardo archive at Yeovil. He has also liaised with Leonardo to enable us to put this volume together.
 

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