The Russian air force will begin receiving new Su-34 fighter-bombers this year. The Su-34 is a modified bomber version of the Su-27 fighter. The Su-34 has a crew of two (pilot and navigator/weapons officer), who sit side by side. The crew enter the crew via a door in the nose wheel bay. The bubble canopy is normally only opened when the ejection seats are used. The Su-34 has a 30mm cannon (with 150 rounds) and can carry up to eight tons of bombs and missiles on ten hard points. The Su-34 will replace the Su-24 and Su-25 bombers. The two engine Su-24 has a max takeoff weight of 44 tons and a max range of 4,000 kilometers. The Su-34 is an all weather aircraft, and is equipped with a terrain following radar for low and fast operations. The Su-34 is a 1980s design that first flew in 1990. The collapse of the Soviet Union stalled development, and delayed introduction of the aircraft by at least ten years. Russia hopes to export Su-34s at well.