Britain's Labour Party radicals yield to a new, more moderate generation

A battle for the political center ground and a drive to give politicians still in their 40s a major say in future political strategy are emerging as the chief aims of the Labour Party's new leader, Neil Kinnock.

A 41-year-old Welsh orator, Mr. Kinnock swept to his first-ballot leadership victory at a party conference that gave him more than 71 percent of the electoral college vote.

At his side will be Roy Hattersley, a 50-year-old Labour moderate, who gained 67 percent of votes for the deputy leadership.

The Kinnock-Hattersley ''dream ticket'' swept all opposition aside. The former party leader, Michael Foot, and his deputy, Denis Healey, both conceded that the leadership torch had been passed to a new generation of Labour politicians.

Most interest is now focused on how the new leadership team intends to restore Labour Party credibility by rescuing it from extreme left-wing policies adopted in the last three or four years.

Mr. Kinnock was formerly associated with pronounced left-wing policies but fought the leadership campaign by suggesting that his views on key issues had moved toward the center.

He and Mr. Hattersley are convinced that Labour lost last June's general election because voters saw the party as too attached to such issues as withdrawal from the European Community and too lacking in unity.

In his acceptance speech, Kinnock said unity was ''an absolute requirement'' if the Labour Party was to retrieve its fortunes. He signaled that he intends to ''jump a generation'' by bringing into the party leadership men and women of his own age.

Party insiders are saying that Kinnock's youthful good looks and relaxed manner are big assets. What they tend not to say is that the leader of the Liberal Party, David Steel, and the leader of the Social Democratic Party, David Owen, are also men still in their 40s, making it vital that Labour should project a youthful image as well.

One of Kinnock's advantages as he settles into the leadership will be the support of Hattersley, who at one point hoped to be leader but quickly realized that he lacked the necessary support. Hattersley represents the Labour Party's moderate wing and had ministerial experience in the last Labour government.

Kinnock has never held a ministerial post. Nor is he as popular among Labour MPs as Hattersley.

The Fleet Street press has been quick to give the new leader a nickname - ''Kinnochio.''

At the Labour Party conference in Brighton Kinnock posed for photographs on a beach, fell, and was drenched by the surf. Fleet Street gleefully printed the resulting pictures.

But Kinnock's chief difficulty in future is unlikely to be the tide around Britain's beaches. The ideological riptide whipped up by the ''hard left'' since the general election defeat of 1979 threatens to be a worse problem.

The Labour Party is saddled with radical policies for nuclear disarmament and extensive nationalization.

Kinnock has indicated that he wants the Labour Party to swerve away from radical commitments and move toward the center. He remains a nuclear unilateralist but believes that by the time Labour fights the next general election, nuclear defense will have receded as an issue.

He wants to make Labour more attractive to property owners and white-collar workers. Above all, he wants to retrieve the party's credibility as a party of government.

Kinnock's supporters are describing him as a champion of the ''realistic left ,'' far more flexible in his ideas than Tony Benn, who remains the darling of the ''hard left,'' although he is now out of Parliament.