Aircraft in 1970 included sixty to seventy fighters and fighter-bombers and about the same number of transports, trainers, and miscellaneous noncombat types. All were of Soviet design. Fighter-bombers or ground attack aircraft were the jet MiG-15s and MiG-17s provided by the Soviet Union before 1961. Spare parts necessary to keep them operating since then have been supplied by Communist China. MiG-19s for the air defense interceptor role have also been furnished by the Chinese. It is believed that the 1970 force included four ground support squadrons and probably two interceptor squadrons, with about ten or twelve aircraft per squadron. Air-to-air missiles are an integral part of the MiG-19 armament and are presumably being furnished in small quantities by the Chinese. Transport squadrons contain a few Soviet-built piston-engined Il-14s and AN-2s, some Soviet-built helicopters, and possibly a few helicopters built by the Chinese. The five principal airbases are located near Tirana, Shijak (about twenty miles west of Tirana), Vlore, Sazan Island (at the mouth of Vlore Bay), and at Stalin (about forty miles south of Tirana). The base on Sazan Island that was built and used by the Russians has been used intermittently, if at all, since the Russians evacuated it in 1961. Helicopter bases have been, or are being, constructed at several inland cities as well as at Tirana, Shkoder, and as a part of the major base at Vlore. The forces had no surface-to-surface missile capability in 1970. The missions assigned to the combat elements of the air force are to repel an enemy at the borders and to prevent the violation of Albanian airspace. Because the force is small, could not easily be resupplied, has exposed bases, and possesses no appreciable area to retreat into, however, it could not be expected to contribute significantly to any sustained combat effort. It serves mainly to provide the regime with ostensive evidence of its power and technological progress. Mobilization Potential In the event of total mobilization there are just under 500,000 males between the ages of fifteen and fifty. Of the total group approximately 75 percent, or nearly 375,000, are physically fit. More than half of these have had some military service, and a sizable group participates in military reserve activities (see ch. 4, The People). Information as to how the existing establishment would be expanded is not available. Units active in 1970 could be enlarged to about double their peacetime strengths because all units are usually maintained at considerably below combat readiness strengths. New units would probably be created in infantry or guerrilla forces. Additional tank, air, and naval units would require more of their special equipment before they could become operational. Some women probably would be mobilized. The national economy, however, could not provide logistic support for the number of male personnel available, and external support would be necessary.