Herbert Pike

Improbable nuclear-weapons pioneer

Herbert Henry Maidmont Pike, nuclear-weapons scientist: born 28 May 1909; research scientist, Woolwich Arsenal (later Armaments Research Department) 1932-47; senior research scientist and Deputy Head of Theoretical Physics, High Explosive Research Establishment (later Atomic Weapons Research Establishment) 1947-72; Honorary Lecturer, Reading University 1973-85; married 1933 Gladys Kellett (died 1985; one son), 1990 Grace Hurd (died 2002); died Poundbury, Dorset 14 May 2003.

The theoretical physicist Herbert Pike was an important member of the team of scientists who developed Britain's nuclear deterrent. He was in at the start, attending the very first meeting to plan the British atomic bomb at Woolwich Arsenal in 1947, and he went on to work at Aldermaston on the hydrogen bomb and on other major weapon developments into the 1970s.

Regarded by colleagues as exceptionally able and wise, he was also in some respects an improbable weaponeer. Tall, thoughtful, mild-mannered and gentle, he made his contributions without fuss or fanfare and on the surface appeared much better suited to the second career he took up on retirement: teaching young archaeologists.

Born in 1909 into a Somerset farming family of modest means, Pike attended Frome Grammar School and Bristol University, both on scholarships, before landing his first job in the research department at Woolwich. He always regarded this as a lucky break - this was 1932 and times were tight - although in truth the atmosphere was stuffy and the science dull. It took the Second World War to inject some dynamism.

Pike's section was evacuated to Cambridge, where he pursued his work on the internal ballistics of guns in the Cavendish Laboratory and helped establish an experimental station nearby at Cherry Hinton. It was a busy, worthwhile period and when peace in 1945 brought him back to Woolwich he feared sinking back into a rut. William Penney saved him from that.

Penney, a member of the British team who had worked at the United States' wartime atomic bomb laboratory at Los Alamos, was put in charge of the Armaments Research Department which had been earmarked by the Attlee government to make Britain's own nuclear weapons.

Pike first worked with him in 1945, helping analyse blast data from Hiroshima that Penney had gathered at the site. But it was in 1947, after the Government finally gave the go-ahead to start work on the bomb, that Pike joined 33 others at the meeting in the Woolwich Arsenal library where the British project was launched.

He was in many respects typical of those involved, scholarship boys from fairly humble backgrounds experienced in the quiet, nuts-and-bolts ways of government military research - a world away from the exotic team of academics and Nobel prizewinners who had worked at Los Alamos.

After initial researches into nuclear blast effects Pike soon took on important work on calculations for the internal physics of the weapon. It was an implosion design like the Nagasaki bomb, in which a jacket of conventional explosive crushed the plutonium core to set off the nuclear chain reaction. The crushing effect had to be almost perfectly even and precise, a great challenge for a team working without American data because the US refused all co-operation.

The mathematical work was done on machines barely more sophisticated than cash registers, so that a single implosion calculation could take Pike's team six months. When the pioneering Ferranti Mark 1 computer came into service at Manchester University at the end of the 1940s, therefore, Pike was quick to see its potential and sent someone to design and run a programme on it; soon Penney ordered a Mark 1 for his department.

Pike's most significant contribution to the first weapon, however, was probably in a redesign of the heart of the bomb in 1950, made necessary by concerns about safe arming. Penney suggested one course but Pike and his immediate superior John Corner proposed another (based on work already done by Klaus Fuchs, the Soviet spy by then already in jail); it was the Corner-Pike approach that was adopted.

Like many others involved, Pike remembered the final phase of preparation for the first weapon test as a frantic, almost desperate time, as he harried the engineers to produce components to the necessary high specifications. Then, when the time came in late 1952, he travelled out to the Monte Bello islands off north-west Australia to witness the explosion.

"We were quite a long way off and there was just a bang," he would say later. "There was nothing very remarkable about it." For all that it was a resounding success; Britain was a nuclear power and Penney got a knighthood.

Pike remained a senior figure at Aldermaston for another 20 years, a trusted deputy to Corner whose contributions included some very difficult studies of possible hydrogen bomb designs and work on the interpretation of American nuclear tests. He also attended some of the British hydrogen bomb trials on Christmas Island in the Pacific.

After his retirement in 1972 he began his second career, teaching science to archaeology students at Reading University, where he is remembered as a kind man who was very good with young people and who each year, in a characteristically generous gesture, took all the staff and final year students out to dinner. The connection with Reading was made through his wife Gladys, who was on the staff there, and he continued to teach until her death in 1985.

At 6ft 3in Herbert Pike was on first acquaintance an imposing figure, though his charm would quickly disarm. He loved travel and spent most of his holidays touring Europe on his motor bike with Gladys, visiting archaeological sites. All his life, however, he was plagued by back troubles, and these eventually immobilised him. After the death of his second wife, Grace, last year, he spent his final days in residential care.

Brian Cathcart