Su-27

Military tungsten alloy cube is usually consisted of W-Ni- Fe or W-Ni- Cu or even W-Ni-Cu-Fe.  Military tungsten alloy cube has high hardness (25HRC~40HRC),excellent elongation and non-toxicity. The most important property for tungsten alloy cube is that small volume with high density, which means it can be used as counterweight for Su-27.

The Sukhoi Su-27  (NATO reporting name: Flanker) is a twin-engine supermanoeuverable fighter aircraft designed by Sukhoi. It was intended as a direct competitor for the large United States fourth generation fighters, with 3,530-kilometre (1,910 nmi) range, heavy armament, sophisticated avionics and high manoeuvrability. The Su-27 most often flies air superiority missions, but is able to perform almost all combat operations. Complementing the smaller MiG-29, the Su-27's closest US counterpart is the F-15 Eagle. The Su-27 entered service with the Soviet Air Force in 1985.