 The "Su-27K" began carrier trials in November 1989, again with Pugachev at the controls, on board the first Soviet aircraft carrier, called "Tbilisi" at the time and formal carrier operations commenced in September 1991.Development of the naval trainer, called the "Su-27KUB" (Russian for "Korabyelny Uchebno-Boyevoy" - "Shipborne Trainer-Combat"), began in 1989.The aim was to produce an airframe with dual roles for the Navy and Air Force suitable for a range of other missions such as reconnaissance, aerial refuelling, maritime strike, and jamming.