21.   Equipped with the latest radar and navigational aids, the center will be able to handle three times as much air traffic as the existing Kai Tak airport.

22.   Flight director Chuck Shaw said he did not expect that to be a problem, since the astronauts have practiced for such a failure and have backup navigational aids.

23.   Hardware in this case is the range of technological navigational aids, instruments and equipment and software, the human factor, according to Lee.

24.   He and his crew had practiced for such a failure and had backup navigational aids.

25.   Jamaluddin said this when asked to comment whether problems with certain navigational aids at the port contributed to the collision between the two ferries.

26.   McMurdo staff were preparing for the unexpected flight and were activating electronic navigational aids.

27.   Modern navigational aids had been ordered and would be installed soon, a port official said.

28.   Most boats are locally made and lack navigational aids.

29.   Thanks to modern navigational aids with satellite and computer technology, the role that lighthouses play in guiding ship crews and preventing wrecks has declined.

30.   The letter cited substandard radar and other navigational aids as well as insufficient Filipino pilots qualified to administer proficiency tests and advise on safety.