Negotiations between Emirates and Rolls-Royce over engine pricing continued at the Dubai Airshow, following a dispute that blocked a deal for Airbus A350-1000 jets. Emirates Airline president Tim Clark warned that engine downtime and high servicing costs were hindering an order for 35-50 jets. A separate deal between Airbus and Ethiopian Airlines for 10 A350-900s was also delayed due to negotiations. Engine pricing has become a key issue for airlines.