aPROFESSOR T R F Nonweiler, who died on December 17, was formerly Professor of Aeronautics at Glasgow University and Dean of the Faculty of Engineering. He was also active in the

university's Cecilian Society and president of the College Club, where he took pride in having improved the range and quality of catering facilities.

In the 1950s, when Nonweiler was at Cranfield College of Aeronautics, his reputation was established in two major areas. The first was man-powered flight, on which he published a paper in the Journal of the Royal Aeronautical Society in October 1958. Although it was praised by Arthur C Clarke in his book The Challenge of the Spaceship, the aircraft he designed was never built.

The other major field was high-speed entry into the atmosphere, either from orbit or from ballistic trajectory. After a paper in the Journal of the British Interplanetary Society and a number of technical reports issued by Cranfield, in September 1951 he spoke at the Second International Congress on Astronautics in London. That paper also appeared in the JBIS and was reprinted by the late L J Carter in the book Realities of Space Travel.

After conducting a three-day symposium at Cranfield in 1957, in 1958 Nonweiler moved to Queen's University, Belfast, where he conducted a major study into the physics of the upper atmosphere, using the effects of drag on the Soviet satellite Sputnik II. Meanwhile, he was approached by Dr Bill Hilton of Armstrong-Whitworth, to study the behaviour of hypersonic shockwaves on the flat underside of the ''pyramid wing'', which he had designed

as a man-carrying vehicle for Britain's Blue Streak Booster.

Computer facilities at the time were inadequate to model the effects and Nonweiler resorted to origami to solve the problem from first principles. In the process he evolved an entirely new principle of flight, the Waverider concept in which the shockwaves would be channelled to the underside of a folded Delta Wing and attached to its leading edges. Nonweiler published the theory in 1959 and was awarded a Gold Medal for it by the Royal Aeronautical Society the following year. In 1962, shortly after Nonweiler became Professor of Aerodynamics and Fluid Mechanics at Glasgow University, a Waverider shape is believed to have been tested at Woomera in Australia, fixed to the nose of a Blue Steel cruise missile.

The British space programme based on Blue Streak had meanwhile been cancelled by the Macmillan government and the Royal Aircraft establishment conducted a high-speed wind tunnel programme to develop a Wave-rider shape for a Mach-6 airliner, published in 1964. Nonweiler continued to work on a small scale with post-graduate students at Glasgow University but in the late sixties and early seventies his main preoccupation was with designing and building a free-fall simulator in the university's James Watt building. Research payloads would be exposed to near-zero gravity for up to half a minute. This would have given Britain a decisive lead in micro-gravity research, but health and

safety officers refused permission for the device to be fired and eventually it was dismantled.

Disillusioned by the failure of still another project, Nonweiler decided to abandon aerodynamic design work and move to New Zealand in 1974 to become Professor of Applied Mathematics at the University of Wellington.

However, his pessimism about Waverider was unfounded. In 1962 Nonweiler joined the Scottish branch of the British Interplanetary Society and remained an active member when it became independent as Astra - the Association in Scotland to Research into Astronautics. He took part in discussion projects which led to the books Man and the Stars, New Worlds for Old, and Man and the Planets, and in April 1970 he opened the society's meeting rooms with a talk on ''The Apollo 13 Disaster''.

At these, and subsequent meetings, he explained the Waverider concept and the vehicle became Astra's ''flagship''. The society's work on Waverider applications and low-speed characteristics attracted the attention of the Jet Propulsion Laboratory, Pasadena, whose Dr Jim Randolph attended a two-day conference with Prof-essor Nonweiler in Glasgow in May, 1988.

Meanwhile, the University of Maryland had independently taken up Waverider studies and in October 1989, it hosted an International Hypersonic Waverider Symposium, co-sponsored by Nasa and attended by more than 100 delegates from research teams around the world.

At the end what he thought had come out of it, Nonweiler said the event had restored his faith in Waverider: ''Surely this time it won't be allowed to die away.'' Sure enough, in May 1994 McDonnell Douglas conducted successful wind-tunnel tests of a Waverider design at speeds of up to Mach 16.5 at the US Navy Surface Warfare Centre, Maryland.

These were followed by tests of a Mach 6 Waverider at Nasa

Langley Research Centre in 1995, and since 1996 Nasa has been running a flight test programme with an experimental Waverider called Lo-Flyte. Dr Randolph's group at the Jet Propulsion Laboratory still hopes to use Waveriders in the exploration of the planets.

Although Professor Nonweiler had been a wheelchair-user for several years, he had continued his work in retirement and recently designed a vehicle based on Waverider to serve as a lifeboat for the International Space

Station. He died at home in Raumati Beach, New Zealand.