The Justice Department yesterday cleared the way for the settlement of last summer's corporate battle between Martin Marietta Corp. and Bendix Corp. by saying that it will not challenge Allied Corp.'s plans to take over Bendix and retain a 39 percent stake in Marietta, a Bethesda-based aerospace contractor.

Allied said last week that it hoped to close the peace agreement by Dec. 21. Some members of the investment community had been getting worried about the amount of time the Justice Department was taking to complete its examination of the proposed agreement, apparently fearing that the deal could collapse or that the company formed by Allied and Bendix would be forced to make fairly substantial divestitures to avoid antitrust complications.

But the Justice Department said yesterday that the review of the agreement had taken an unusually long time "because it involved an extensive inquiry into a large number of product markets and required the collection and analysis of data from many corporations and individuals."

Bendix and Martin Marietta locked in a dogfight in late August, eventually buying majority positions in each other. Allied entered the fray late in September, proposing to take over Bendix for $2 billion and then trade part of Bendix's holding in Marietta for the Bethesda company's Bendix shares.