 Approximately 40 flights were conducted before the second prototype took to the air on 2 October from KnAAPO 's <unk> Airport , again piloted by Sergey Bogdan . The Su @-@ 35 had earlier in July made its first demonstration flight in front of Defence Ministry and foreign officials . At the time , Sukhoi estimated that a total of 160 Su @-@ 35s would be supplied to customers worldwide , in particular those in Latin America , Southeast Asia and the Middle East . Domestically , the VVS Commander @-@ in @-@ Chief Colonel General Alexander Zelin stated that the service was seeking enough aircraft , estimated to be 24 – 36 units , to equip " at least two to three regiments " . 
