The flotilla consisted of ships owned or chartered by a number of non-governmental organizations, including the Free Gaza Movement (FGM), the Turkish IHH, and the Greek Ship to Gaza. The lead ship was the Turkish-flagged Mavi Marmara, carrying more than 500 activists on board.
The US-flagged Challenger 1 is operated by the Free Gaza Movement.
Greek-flagged cargo vessel operated by the Swedish-Greek organisation Ship to Gaza. Also called the Eleftheri Mesogeios (Eλεύθερη Mεσόγειος, Free Mediterranean).
The Sfendoni (Σφενδόνη, Slingshot) is a Greek-flagged passenger vessel operated by the Greek Ship to Gaza and the European Campaign to End the Siege of Gaza. Left the port of Piraeus together with the Sofia on 25 May to rendezvous with the rest of the flotilla off Cyprus.
MV Mavi Marmara
The Mavi Marmara ("Blue Marmara") is a Comoros-flagged passenger ship, which was formerly owned and operated by Istanbul Fast Ferries Co. Inc., in the Sea of Marmara. It was purchased especially for the trip to Gaza by the İHH.
It left the Anatolian port of Antalya on 22 May 2010 to rendezvous with the flotilla heading to Gaza, along with the Gazze and Defne Y. It carried 581 activists, around 400 of whom were Turkish.
The Gazze ("Gaza") is a Turkish-flagged cargo vessel owned and operated by the Turkish Islamic charity IHH. Its cargo consisted of 2,104 tons of cement, 600 tons of construction steel, and 50 tons of tiles. It also carried 13 Turkish crew members and 5 activists. It left Antalya on 22 May to rendezvous with the flotilla, along with the Mavi Marmara and Defne Y.
The Kiribati-flagged Defne Y ("Laurel Y") is a cargo ship owned and operated by the Turkish Islamic charity IHH. It carried a mixed cargo of goods including 150 tons of iron, 98 power units, 50 precast homes, 16 units of children's playground equipment and various items of specialist medical equipment. There were 23 crew and 7 activists on board. It left Antalya on 22 May to rendezvous with the flotilla, along with the Mavi Marmara and Gazze.
MV Rachel Corrie
The Cambodian-flagged Irish Rachel Corrie, named after Rachel Corrie, an American college student crushed to death by an Israeli army bulldozer while protesting house demolitions in Gaza, was unable to join the rest of the flotilla because of mechanical problems that forced it to undergo repairs in Malta. The aid-carrying vessel got underway on 31 May 2010 after the interception of the flotilla, with its crew insisting that they would go to Gaza. The vessel is a former merchant ship owned and operated by the Free Gaza Movement. The ship was checked for weapons in Ireland by customs officials and a senator from the Irish Green Party. No weapons were found. Irish Prime Minister Brian Cowen called on Israel to allow its passage. Ireland later reached an agreement with Israel and made a proposal to the ship that it divert to Ashdod, where Israel offered to transfer its cargo to the Gaza Strip, under the supervision of passengers and Irish diplomats. The passengers of the ship rejected the offer. Israel reported its troops have taken control of the ship on June 5 about 16 nautical miles (30km) off the coast. IDF spokeswoman said there "was full compliance from the crew and passengers on board".
The US-flagged Challenger II, a Free Gaza Movement ship, was also unable to join the rest of the flotilla due to mechanical problems. It is currently undergoing repairs in northern Cyprus. The Free Gaza Movement suspects sabotage by Israeli agents to be the cause of the malfunctions in the Challenger I and Challenger II.