Sir David is currently Chairman of the Hazards Forum and Master of the Worshipful Company of Engineers.

He was formerly Chairman of Railway Safety until May 2003. He was President of the Royal Academy of Engineering from 1996-2001 and Chief Scientific Adviser to the Ministry of Defence from 1993-1999. He was born in Cardiff and educated at the University of Birmingham , from which he graduated in electrical engineering, undertook research for a PhD and subsequently joined the staff.

In 1967 he was appointed Assistant Director of Research at British Railways and in 1971 was appointed Professor Electrical Engineering at University College London. In 1988 he became Vice-Chancellor at Loughborough University of Technology until he moved to the MOD. He was elected to the Royal Academy of Engineering in 1979 and to the Royal Society in 1984. He was awarded a CBE in 1986 and appointed Knight Bachelor in 1994.

Sir David was President of the Institution of Electrical Engineers in 1994/5 and was elected President of The Royal Academy of Engineering in 1996 for a 5 year term. He has been a non-executive director of Lattice Group plc and ERA Technology Ltd. In October 1999 he was asked by the Deputy Prime Minister to produce a report on Automatic Train Protection. Following this he was appointed Chairman of Railway Safety, a new company limited by guarantee set up to promote and oversee railway safety issues.

Sir David has researched and published in the fields of antenna arrays, radar systems, signal processing and optical fibre sensors. He received the Rank Prize for Optoelectronics in 1984 and the Faraday Medal of the IEE in 1987. He has received honorary degrees from several universities.

His interests include cars, opera and organ music.

He married his second wife, who is a chartered surveyor, in November 1992, and has two sons and a daughter.