The soaraway Yen and the gathering thunderclouds of trade war have persuaded Hitachi Ltd to advance by a full three years its plans for mass production of large-scale – up to 5Gb – disk drives at its new US plant in Norman, Oklahoma, which began operation only in April: the company will double its planned investment to $50m, and the bulk of output – valued at $25m this year and set to grow to $200m by 1991, will initially go to National Advanced Systems and European resellers such as Comparex in Germany.