The international use of aircraft brought up questions about air sovereignty.

Other threats were identified during the late 1990s, including terrorists' use of aircraft as weapons.

"The use of naval aircraft would be an act of war," the President said.

Military transport helicopters are used in places where the use of conventional aircraft is impossible.

Today, it is considered a significant aviation film by historians due to the use of contemporary aircraft.

He said the use of aircraft was one thing that would raise costs.

He was a pioneer in the use of aircraft, military and civilian.

He then went to Australia to promote the use of aircraft on sheep farms.

To maximise the use of aircraft, night flights were used.

During these years the Survey made use of aircraft in its activities for the first time.