Chichester-Miles
Chichester-Miles Consultants Ltd
Contents
History
Ian Chichester-Miles was born on 26 April 1926 in Harpenden, Herts, the son of Herbert Glencairn Wright Chichester-Miles and Gertrude Florence Chichester-Miles (née Lay). He was educated at Bedford School and at Loughborough University, where he studied engineering. He became an aerospace engineer, starting in 1947 with de Havilland at Hatfield on the structures of the D.H.108, D.H.110 and Comet. At other companies he worked on jet-driven helicopter rotors, jet-augmented wing lift, and nuclear-powered marine engines. He also took out a patent for ultra-high pressure structures.
In the 1960s he was Chief Research engineer at Hatfield exploring the feasibility of vertical take-off airliners. At that time the aerospace industry was much motivated by vertical take-off and the success of the military Harrier. His work at Hatfield with Derek Brown on the D.H.129 vertical take-off transport project won a NATO competition and heralded civil airliners which would take off and land in city centres. He worked with the German company Dornier, which flight-tested the experimental Do31 vertical take-off transport, but he grew doubtful about the noise, weight and fuel efficiency of multiple lift-engines.
On retiring from his post as Chief Research engineer in the late 1970s, he had come to realise the potential of jet engines in smaller aircraft and believed that aviation technology would allow the design and manufacture of an affordable, jet-powered “personal aircraft”. Chichester Miles Consultants (CMC) was formed on 05 January 1978, based at Old Sarum airfield near Salisbury, and began to design a proof of concept aircraft. Design of the privately funded aircraft began in earnest in January 1981 and 13 months later a full-size mock-up emerged. In 1982, under contract to CMC, the Leopard prototype detailed design and construction was begun by Designability Ltd of Dilton Marsh, Wiltshire. The Leopard’s swept-back wing, combining supercritical and laminar flow technology, was developed by the Aircraft Research Association at Bedford, who provided the computational fluid dynamics capacity and high-speed wind tunnel essential to the programme.
The Leopard 001 first flew in 1988 using British jet engines from Noel Penny Turbines. This aircraft was simply a proof of concept aircraft it had basic controls, rudimentary fuel and avionics systems and lacked such essentials for a production aircraft as cabin pressurisation and air-conditioning. Unfortunately, at only 300 lb thrust, the Noel Penny powerplants were not powerful enough to realise his vision of a 500 mph aircraft, and the program suffered a setback when Noel Penny went out of business.
During his BAe days, Chichester-Miles had got to know Sam Williams very well, and in the early 1990s persuaded him to supply him some larger turbofan engines for Leopard 002. Accordingly, CMC proceeded with the detailed design and specification of the Leopard 002 powered by two Williams International FJX-I turbofans of 700lb thrust. Although externally identical to the first aircraft, the second prototype was completely redesigned using CAD/CAM techniques. Leopard 002 first flew in 1997, and appeared at the Experimental Aircraft Association's air show in Oshkosh, Wisconsin, in 1999.
Continually the company sought investors for their programme, pitched by 1996 at £25M including further development airframes. Plans were made to power later aircraft with the enhanced Williams FJX-2 engine, and fly that variant during 2000. However, a grave problem emerged as once again as supply of engines was denied CMC. Williams International signed an exclusive agreement to sell the production Leopard’s planned engine, the FJX-2, to Eclipse Aviation for its Eclipse 500 twin-jet.
Failing to find another suitable powerplant, CMC drew up a six-seat variant of its aircraft which it named the Leopard Six, Chichester-Miles explaining that the company had concluded there was no alternative but to alter the Leopard design to fit the larger 1,500lb thrust Williams International FJ33 turbofan. The Leopard Six was targeted to appear in 2004, and to fund the new programme through to certification, CMC announced it was seeking investment of $95 million. However, by 2004, instead of yielding hardware, development of the Leopard Six had ceased; the aeroplane faced growing competition and establishing production, finding launch customers and providing after-sales support — especially overseas — were always truly massive challenges.
Ian Chichester-Miles died on 2 June 2009 in Ayot St Lawrence, Herts, and with that, the program ceased.
Company References
Project Data
| Project No | Type No | Name | Alternative Name(s) | Year | Spec (Requirement) | Status | Qty | Description | References |
|---|---|---|---|---|---|---|---|---|---|
| Leopard | Leopard Four | 1981 | Proto | 2 | 4S, 2E sports & business jet | 1, 3, 4, 5, 9, 10 | |||
| Leopard Six | 1998 | Proj | 0 | 6S, 2E sports & business jet | 2, 6, 7 | ||||
| Leopard T-Jet | 1998 | Proj | 0 | 2S, 2E jet trainer | 8 |
Project References
- Air International Nov 1986
- Air International Jan 1999
- Flight 3 Jul 1986
- Flight 8 Jul 1989
- Flight 8 Apr1992
- Flight 20 Mar 2001
- Flight 18 May 2004
- https://www.secretprojects.co.uk/forum/index.php/topic,4474.0.html
- https://acasestudy.com/chichester-miles-consultants/
- Janes All The Worlds Aircraft 1990-91, Ed. Mark Lambert (Janes Publishing, 1991)
Production Details and Type Description
Twin-jet, mid-wing monoplane of composite construction with all-swept flying surfaces and jet fighter-like styling, apart from the podded engines, mounted on each side of the rear fuselage. The entire canopy hinged forward to allow access to the four reclining seats. The wings were a two spar structure, primarily of GFRP, with full span trailing edge flaps. The fuselage, a monocoque GFRP structure, was built in three parts: the nose section, pressurised cabin section (not first prototype) and rear sction containing fuel tanks and baggage compartment. Fuselage frames were moulded in. The all moving fin and tailplane was also an all composite structure, the latter acting collectively for pitch and differentially for roll control.
| Specification | |||||||||
| Span | Length | Height | Wing Area | Empty Wt | Max AUW | Cruise Speed | Maximum Speed | Range | Service Ceiling |
| 23 ft 6 in | 24 ft 8 in | 6 ft 9 in | 62.9 sq ft | 1900 lb | 3750 lb | 540 mph/ 469 kn | 1725 mi | 55000 ft | |
| 7.16 m | 7.52 m | 2.06 m | 5.84 m2 | 862 kg | 1701 kg | 869 kph | 2776 km | 16764 m | |
Total Chichester-Miles Production2