The Anglican Catholic Church, the name chosen by former Episcopalians for their fledgling denomination, got off the ground here Oct. 21, but its launching was rocky and uncertain.

About 140 lay and clerical delegates from across the country approved, on a nonbinding basis, a provisional constitution at the denomination's first convention. Although the vote was nearly unanimous, there were no cries of victory and jubilation in the aftermath of a meeting that was marked by tension and maneuvering.

The first motion approved by a 75-to-53 vote, was for a "secret session" so that the assembly need not "discuss red-hot issues in front of the public and press."

From vantage points outside, reporters heard what some called personal attacks on divorced priests and a group of so-called "troublemakers." The outcome was a motion to oust the Southwest Diocese (Texas and Missouri) on the ground that it had not been properly organized. When the four bishops split on their vote, the delegates voted to uphold the report of the credentials committee to permit the Southwest Diocese to have full status.

This prompted two dioceses, Christ the King and Southeastern United States, to stage a walkout to a room on the floor above, where they began deliberating the possibility of constituting a "Continuing Anglican Church" on their own.

Bishop James O. Mote of the Diocese of the Holy Trinity, Denver, finally told the walkout dioceses: "It is unconscionable to sabotage a Catholic constitution for the sake of one diocese. I will change my vote if that is the only way. I will vote not to seat the Southwest Diocese if you believe they have not fulfilled the necessary conditions."

Led by their prelates, Bishops Peter Watterson of West Palm Beach, Fla., and Robert Morse, of Oakland, Calif., the two dioceses returned to the ballroom. They brought with them a "4-point mandate" that called for the bishops to take the chair of the meeting, to dissolve the assembly and convene a synod, to give the diocese of the Southwest a voice but no vote.

Charles Bucy, a delegate from Dallas, said that "this is an issue of raw, naked power, with you saying, "If you don't play the game my way, we're leaving." But by a vote of 77 to 69, the mandate was adopted.

The vote on the Constitution was unanimous approval among the laity and clerical delegations. Only Bishop Morse refrained from approval among the bishops.

The constitution now will be returned to the seven dioceses. If four of them approve it, it will be the official vehicle for setting the theological and governmental standards for the denomination.

Accurate statistics on the new church's membership are unavailable. Its leaders have contended that disgruntled members of the 2.8 million-member Episcopal Church in this country are watching its development closely with an eye toward joining the break-away group once it is formally established as a church in the Anglican tradition.

Delegates were so divided that some actions were decided by 1 or 2-vote margins. One of the few acts to trigger a standing ovation and unanimous approval was a letter of welcome signed by Bishops A. Donald Davies and Robert Terwilliger, the Dallas diocesan and suffragan, respectively, of the Episcopal Church from which the delegates to this meeting had split.