Adm Ozer Karabulut is among those accused of plotting a coup
Twenty military officers have been formally charged in Turkey with attempting to overthrow the government.
They include four admirals, a general and two colonels, some of them retired.
The men were among more than 40 officers arrested on Monday over an alleged 2003 plot to stir up chaos in Turkey and justify a military coup.
The head of the armed forces, General Ilker Basbug, will meet the country's prime minister and president later to discuss the alleged plot and arrests.
The meeting was called after the country's top generals and admirals met at short notice on Tuesday to evaluate what the military called a "serious situation".
The scale of Monday's operation against the military was unprecedented and increased the tension between the government and the armed forces.
Dozens of current or former members of the military have been arrested in the past few years over similar plot allegations, and some have been charged.
This is now turning into a critical test of the government's authority over the military, says the BBC's Jonathan Head in Istanbul. Never before have so many senior officers faced charges like this in a civilian court.
The charged men were arrested over the so-called "sledgehammer" plot, which reportedly dates back to 2003.
Reports of the alleged plot first surfaced in the liberal Taraf newspaper, which said it had discovered documents detailing plans to bomb two Istanbul mosques and provoke Greece into shooting down a Turkish plane over the Aegean Sea.
The army has said the plans had been discussed but only as part of a planning exercise at a military seminar.
The alleged plot is similar, and possibly linked, to the reported Ergenekon conspiracy, in which military figures and staunch secularists allegedly planned to foment unrest, leading to a coup.
Scores of people, including military officers, journalists and academics, are on trial in connection with that case.
Analysts say the crackdown on the military would have been unthinkable only a few years ago.
HOW 'COUP PLOTS' EMERGED
June 2007: Cache of explosives discovered; ex-soldiers detained
July 2008: 20 arrested, including two ex-generals and a senior journalist, for "planning political disturbances and trying to organise a coup"
July 2008: Governing AK Party narrowly escapes court ban
October 2008: 86 go on trial charged with "Ergenekon" coup plot
July 2009: 56 in dock as second trial opens
Jan 2010: Taraf newspaper reports 2003 "sledgehammer" plot to provoke coup
Feb 2010: More than 40 officers arrested over "sledgehammer"; 20 charged
The army has regarded itself as the guardian of a secular Turkish state. It has overthrown or forced the resignation of four governments since 1960 - the last time in 1997.
But the power of the army has been eroded in recent years, with Turkey enacting reforms designed to prepare it for entry to the European Union.
And General Ilker Basbug, the head of the army, has insisted that coups in Turkey are a thing of the past.
Many Turks regard the cases as the latest stage in an ongoing power struggle between Turkey's secular nationalist establishment and the governing AK Party.
Critics believe the Ergenekon and sledgehammer investigations are simply attempts to silence the government's political and military opponents.
The AK Party has its roots in political Islam, and is accused by some nationalists of having secret plans to turn staunchly secular Turkey into an Islamic state.
The government rejects those claims, saying its intention is to modernise Turkey and move it closer to EU membership.