Although his manner and accent were those of the patrician establishment - an essential asset in the internal politics of the BBC's bureaucracy - his vision was radical and subversive of the corporation's top-down value system. He respected the subjects of his films. He believed they had something to say that was worth hearing. And he saw his role as a technical enabler, allowing them to say it.
The people he filmed demonstrate his determination to open the ether to voices that usually go unheard - seafarers and fishermen, steelworkers and miners, Irish migrants and travelling people. Asked once what had happened to the creativity of the working class, he replied: "It's in their speech." Such an approach does not endear you to the mandarins; he was seen as a maverick throughout his working life. But he survived the system for 36 years and managed to make nearly 100 films, most of which were broadcast; some won awards.
Philip Donnellan was born in 1924, the son of a schoolmaster in Reigate. Leaving his boarding school at 16, he trained as a reporter on local newspapers in Surrey, dashing about on a bicycle to see where bombs had landed. War service in the Army - he joined the Seaforth Highlanders on his 18th birthday to get as far away from home as possible - took him to India, Burma, Malaya, China and North Africa with No 5 Commando and ended in Intelligence in Gibraltar.
In 1948 he applied to join the BBC in Birmingham and, although he heard of his father's death on the morning of his interview, he got the job - first as a radio announcer and newsreader, then as a writer and producer of radio features which were carefully scripted and read live by actors in the studio. When portable tape recorders became available in 1954 he moved into the collection and editing of actuality, along with Charles Parker, creator of the sound collage Radio Ballads.
Donnellan moved into television as a documentary producer in 1958, working exclusively on film and developing the contrapuntal use of sound and image. He was known as an extravagant producer, using vast quantities of film stock when only a small amount was shown; he was a perfectionist.
Much of his television work paralleled what Parker was doing in radio - using the words and songs of ordinary working people, directly presented without the intervention of an intermediary commentator, to share their experiences and concerns. It was typical of his openness and honesty that he would show the crew filming - in Brechtian style, he liked to expose the real situation.
When he made The Fight For Shelton Bar in 1973, about the struggle against the threatened closure of a Staffordshire steelworks, he invited the steelworkers into the cutting room to help edit it. The BBC chucked them out on the grounds of editorial independence.
The theatre director Peter Cheeseman applied the same techniques to his work on stage at the Victoria Theatre in Stoke-on-Trent, creating company- devised musical documentaries scripted from interviews with ordinary people. All three men were involved with Ewan MacColl and Peggy Seeger in the folk revival, excavating and celebrating the traditional music and oral heritage of the working class.
"He was bloody impossible to work with," Cheeseman says, "but when you made a film with Philip you were his friend for life." His passionate commitment to the subjects he filmed continued after the broadcast - after Where Do We Go From Here? (1967) about travelling people, he became involved in gypsy liaison groups; after making BD8, about the problems of blind people, in 1968, he founded the Shropshire Talking Newspaper for the Blind.
His films reflected his obsessions - with the sociology of industrial life (Joe the Chainsmith, 1958); with marginalised minorities (The Colony, about West Indians in Birmingham, 1964); with authority and the individual (Six Men, about men of power in 1965); with imperialism and its consequences (biographies of Nehru, de Gaulle, Nkrumah, T.E. Lawrence); with working- class culture (Half a Smile from Stoke, about the Potteries painter Arthur Berry, 1976).
But the films he would probably most want to be remembered for are Pure Radio (about broadcasting history, 1977) and Gone for a Soldier (1980), a two-parter about squaddies in the British Army from 1815 to 1979 which caused a furore for its anti-war empathy with the other ranks.
A tall, imposing figure, in the early days Donnellan was something of a dandy. One close colleague remembers him with a silver-tipped cane saying, "You must come back to my chambers", which turned out to be a dingy room in a boarding house. Later he changed his image, wearing fishermen's smocks and, intermittently, a beard.
His widow, Jill (they met in 1948 at Bush House, where she was a secretary with the BBC World Service and later became an announcer herself) says the change of style was a slow evolution. "At first he was absolutely dashing in a tweed suit, everything matched," she says. But when he moved from being a newsreader to a documentary producer he dressed down to blend with the ordinary people he was interviewing - "That's why people talked to him so well." They moved from the Daily Telegraph to The Guardian at the time of Suez.
"I might have been playing golf and bridge for life if I hadn't met him," Jill says. "But through him I have met an extraordinary range of people." Together they built up a collection of about 100 pieces of vernacular pottery - handmade or decorated mugs, jugs, loving cups as used for serving drink by ordinary people - which is now lodged on permanent loan at the New Victoria Theatre in North Staffordshire.
Philip and Jill had four children. Tom is a lighting designer in Spain; Rebecca a broadcaster in France; Philippa a dancer in London and Polly a community worker in Kilkenny. "He was a bloody hard man to live with," Polly says, "but he made me aware of the people around me."
In 1988 he wrote a book, We Were the BBC, which Jill describes as "a non-Asa Briggs history". It awaits publication. Most of his films are kept by the British Film Institute; those with an Irish theme (his family came from Galway) are in the National Film Archive in Dublin.
Philip Donnellan, documentary film-maker: born Reigate, Surrey 9 February 1924; married 1952 Gillian Berry (one son, three daughters); died Passage West, Co Cork 15 February 1999.