air clearance造句

• The Haihe Bridge is directly over the shiplock, with an air clearance of 39.5 m.
• Brady then requested mortar fire in support; however, the need to request air clearance only resulted in further delay.
• This year, the United Nations gave Egypt Air clearance to make 40 flights from the capital Tripoli and Benghazi, Libya's second-biggest city, to the Saudi Red Sea port of Jeddah.
• The main line locomotives were not fitted with voltage switching mechanisms, and as the air clearance requirement had been relaxed in the intervening years, the 6.25 kV section was converted to 25 kV from September 1973.