Japanese hard rock/heavy metal project established by 70's rockers. Their music is a mix of early heavy metal sound and 70's hard rock. Powerful riffs, melodies and... lots of keys/organs, it sounds little like "Judas Priest meets Deep Purple". HMA released (in 1981) only one album (called simply Heavy Metal Army" or "1"), later vocalist Hiroto Arasaki (known also as John Joseph Patterson), keyboardist/vocalist Yuki Nakajima and drummer Eiichii "Chibi" Miyanaga (Murasaki) established Eastern Orbit