The Federal Aviation Administration won't allow Boeing to hike output of its narrowbody beyond a 38-jet monthly pace until it's convinced quality controls are in place and the supply chain can keep pace. Output has risen a little at the US planemaker, which delivered its highest monthly total in June since the January incident. Increased deliveries are vital for Boeing to bolster finances that have been battered by a production slowdown as it retrained workers and stepped up supplier inspections. Boeing shares fell less than 1% at 9:45 a.m. in New York.