A trial involving 800 cases of human rights abuses during Argentina's 1976-1983 military junta is set to open Wednesday, chronicling the use of torture and murder during the dictatorship.

The trial in Buenos Aires, "was, is and will be the largest trial of crimes against humanity" in Argentina, said rights attorney Rodolfo Yanzon.

"There are 68 defendants charged in 800 cases, and we estimate there will be some 900 witnesses," he told AFP, adding that testimony in the case could take between 18 and 24 months.

The infamous "death flights" -- the practice of throwing live prisoners into the sea from aircraft -- will figure prominently in the trial, Yanzon said.

Some 30,000 people were kidnapped, tortured and killed in what became known as Argentina's "Dirty War," according to rights groups. Victims included Montonero guerrillas, labor union leaders, students, and leftist sympathizers.

The trial is part of an effort to probe torture and crimes against humanity committed at a notorious ESMA Naval Mechanics School -- 5,000 regime opponents are believed to have been sent to ESMA, of which only a fraction survived.

Included in the trial will be the case of French-born nun Leonie Duquet, who was allegedly kidnapped and killed on a "death flight."

The bodies of Duquet and three members of the Mothers of the Plaza de Mayo -- a rights group helping regime victims -- washed up on a beach in Buenos Aires province in 1977. Locals initially buried the women under headstones that read "NN," or no name.

The trial's defendants include eight "death flight" pilots -- among them is Julio Poch, a Dutch national and a former Argentine naval aviator extradited from Spain in May 2010.

Until his arrest Poch was working as a pilot for Transavia, a subsidiary of Air France and KLM. His work colleagues turned him in when Poch recounted stories from his days in the Argentine navy.

Other defendants include former navy captain Alfredo Astiz, the "Blonde Angel of Death," who allegedly helped kidnap four members of the Mothers rights group, including its founder Azucena Villaflor, as well as Duquet and Alice Domon, another French nun who is still missing.

An Argentine court sentenced Astiz to life in prison for torture, murder and rights abuses in October 2011.

Pro-junta civilians will also be on trial, including former finance minister Juan Alemann, who allegedly witnessed the torture of a man suspected of attempting to murder him.

A blanket pardon for dictatorship crimes was overturned in 2003, paving the way for lawsuits.

In September a Crimes Against Humanity Board report found that between 2008 and July 2012 there were 61 trials for crimes committed by the military dictatorship, with 270 convictions.