Nabeel Hussain, Mohammed Yasar Gulzar and Mohammed Shamin Uddin were among the 25 people arrested since police staged pre-dawn raids on August 10 in connection with the plot.
Five have since been released without charge. Police also have warrants to quiz the remaining five until Wednesday.
Under British anti-terror laws, suspects can be detained for up to 28 days without being charged, subject to regular court approval.
Hussain, Gulzar and Uddin bring the total number of the terror suspects to face the most serious charge of conspiracy to murder to 11. They will appear at City of Westminster Magistrates Court later today.
The three allegedly "conspired with other persons to murder other persons" and acted "with the intention of committing acts of terrorism", intending "to smuggle the component parts of improvised explosive devices onto aircraft and assemble and detonate them on board," police said.
Umair Hussain, 24, was last week charged under anti-terror legislation for allegedly failing to disclose information about Nabeel, his brother.
Liquid bombs
Of the remaining 11 facing charges, eight others, in addition to the three charged on Tuesday, are accused of conspiracy to murder and preparing acts of terrorism, and will appear in court again on September 4.
They are Ahmed Abdullah Ali, 25, Tanvir Hussain, 25, Umar Islam, 28, Arafat Waheed Khan, 25, Assad Ali Sarwar, 26, Adam Khatib, 19, Ibrahim Savant, 25, Waheed Zaman, 25.
The remaining three were remanded in custody on Tuesday when they made brief appearances in court.
Security at British airports was stepped up to unprecedented levels in the aftermath of the police raids on August 10, with the country upgrading its threat level to "critical" -- the highest of five levels.
The suspects were allegedly planning to smuggle seeming innocuous liquids on to planes with the intention of assembling them into bombs on board.
The alleged plot was described by one senior police officer as "an attempt to commit mass murder on an unimaginable scale".