The light aircraft, including a Provost training jet still bearing the markings of the Royal Air Force, are commemorating the first anniversary of the shooting of two US civil aircraft by Cuban MiG fighters.
The shootings, in which four Americans of Cuban origin were killed, led to a dramatic hardening of policy towards Cuba by US President Bill Clinton and a subsequent rift between the US and the European Union over how to treat Fidel Castro's regime.
The aircraft shot down belonged to the Brothers to the Rescue group of Miami-based Cuban-Americans who try to spot fleeing Cuban "boat people" and occasionally dropped anti-Castro leaflets over the Cuban coast. A year ago today, Cuba claimed they had entered its airspace, but US data showed they were in international airspace at the time.
US officials warned today's protesters not to provoke Mr Castro by entering Cuban airspace. The officials said the Provost aircraft, because of its RAF markings and history as a military trainer, should not fly past the halfway mark of the 90 miles between Key West, Florida, and the Cuban coast. The others will fly closer to Cuba and drop wreaths near the site of last year's shootings.
The officials said all US radar stations in the region would be on special alert, including the Norad system aimed at protecting the US from any nuclear missile attack.
The leader of Brothers to the Rescue, Jose Basulto, who narrowly escaped a chasing MiG fighter a year ago, said Florida-based US jet fighters could have and should have taken action to prevent the shootings. The US State Department has called on the pilots and the Cuban government not to provoke a new incident today and Cuba has said it will "take all measures necessary to prevent a violation of our airspace".
After last year's shootings, President Clinton abruptly changed tack and backed the Republican-sponsored Helms-Burton law tightening sanctions and discouraging foreign investment in Cuba. Mr Clinton urged the rest of the world to join a "choir of democracy" against Mr Castro's Communist regime.
That led to a year of conflict with the European Union, which mostly believes doing business with Mr Castro is the best way to bring him into the democratic fold.
The dispute is now the focus of the World Trade Organisation, where the European Union has challenged the Helms-Burton law as restricting the principle of free trade. The US says that, because of Mr Castro's communist regime and its proximity to US shores, the law is an issue of US national security.
Mr Clinton's hardened stance last year was also seen as something of an election year coup which turned the votes of many Cuban-Americans, mostly Republican by tradition. Mr Clinton has twice offset EU concerns by suspending a key provision of the law which would allow US lawsuits against foreign companies doing business with Cuba in certain cases.