They were remanded by Magistrate Timothy Workman at the City of Westminster magistrates court in London.
Their court appearance came 12 days after police revealed the alleged plot to use liquid explosives to bomb up to 10 planes.
The accused are mostly Muslim men from East London, but also include a young mother and a 17 year old youth.
Charges laid
Eight of the 11 suspects are facing the most serious charges of conspiracy to murder and preparing acts of terrorism.
They are: Hussain, 25; Umar Islam, 28; Arafat Waheed Khan, 25; Ahmed Abdullah Ali, 25; Ibrahim Savant, 25; Waheed Zaman, 22; Assaid Ali Sarwar, 26; and Adam Khatib, 19.
The 3 others have been charged with withholding information about an impending terrorist attack.
The 17-year-old youth has been accused of possessing items which police say would be useful to someone planning an attack.
The items include a book about bomb-making, suicide notes and wills and a map of Afghanistan.
Due to his age, he alone was allowed to sit in the centre of the courtroom, and not in the dock to the side.
The men wore white sweatshirts, grey jogging pants and trimmed beards, flanked by five guards. The woman wore a hijab, or headscarf.
The accused spoke only to confirm their names, dates of birth and addresses. No pleas were entered and only one asked for bail.
Charges denied
Mohammed Zeb, a lawyer for one of the accused, Tanvir Hussain, stated that "all allegations are denied".
Lawyers for the only woman, Cossar Ali, 23, Mehran Hussain, also 23, and the teenager have indicated they would plead not guilty.
The eight alleged bomb plotters have been ordered to reappear in court on September 4.
They will reappear before judge Anne Rafferty at the Old Bailey court in central London.
The Old Bailey is traditionally used for Britain's biggest criminal trials. The three others are to return to the magistrates court next Tuesday.
Another 11 people remain in police custody for questioning but have not been charged.
Two others who had been arrested on or after August 10 have since been released.
Investigation continues
Police have stressed that the threat of terrorism is real but moved to assure the public that they are doing all they can to stop extremists.
"The investigation is far from complete. The scale is immense. Inquiries will span the globe," said Peter Clarke, chief anti-terrorist officer at London's Metropolitan Police.
Seven other people, including two Britons, are being held in Pakistan, where the authorities have suggested a possible link with Osama bin Laden's al-Qaeda network, which carried out the September 11 attacks in the United States.
Meanwhile a security alert was triggered at London's Luton regional airport after police say a note was found on an airplane on the ground.
The plane was being cleaned at the time and no one was on board.
A piece of paper that had been scribbled on had been found on the plane but officials later gave it the all clear.
British airports have been on a heightened state of alert for almost two weeks since the alleged bomb plot was revealed.
Hand luggage was banned on all US bound flights prompting airport chaos for travelers.
Meanwhile, a junior minister in Prime Minister Tony Blair's government said it would take "generations" to overcome extremists who want to destroy society.
"We see this fight against terrorism as a perpetual fight," said Communities Minister Phil Woolas at a meeting of leaders from various faiths in Bolton in northwest England.