American’s purchase of AirCal stock was OKd.

The U.S. Department of Transportation action gave American Airlines approval to acquire 70.4% of the common stock of ACI Holdings, parent of Newport Beach-based AirCal, and place it in a voting trust until it completes its proposed $225-million purchase of ACI. An American spokesman said the stock trust “protects us from other potential tender offers” for AirCal until the DOT rules on whether American may complete the merger.