Atlanta ? The leaders of the pilots union at Delta Air Lines Inc. have ratified a tentative agreement, endorsing concessions that include an initial 14 percent wage cut and assurances the union won’t block any company effort to terminate its pension plan.

The vote by the leadership was 12-1 in favor of ratification, according to a memo sent late Friday to pilots, who will be asked to approve it.

The agreement was reached between the nation’s third-largest carrier and union negotiators on April 14, clearing one hurdle for Atlanta-based Delta by avoiding a crippling strike.

Now comes what could be the harder part – getting the airline’s 5,930 pilots, who came to the brink of a walkout, to approve the deal.

The balloting will begin in mid-May and remain open for 15 days.