The Sukhoi Su-27 'Flanker' was designed in opposition US aircraft such as the F-14, F-15, and F/A18. It is a large Air Superiority Fighter, capable of long range, and carrying a large array of weapons on 10 x Hardpoints. It entered full service in the USSR in 1986, and also proved to be incredibly agile as demonstrated at numerous air shows around the world.
More advanced versions (Su-30, 33, 34, 35) are appearing all the time, but the basic Su-27 is in service with many air forces from Angola to Vietnam.
The Su-27 is armed with 1 x 30mm cannon, and up to 6 x R-27 medium-range missiles, and 4 x R-73 short-range missiles.
This example is an Su-27S of the Belarus Air Force, circa 2004.