This meant that a single navigation instrument could replace both short and long-range navigation systems, offer better accuracy than either, and required no ground-based equipment.

The failure in navigation has been ascribed to an out-of-adjustment celestial navigation instrument, a bubble octant, that gave a systematic bias to all of its readings.

The pilot, who had asked passengers to switch off their mobiles on three occasions, aborted takeoff at the last minute after noticing interference with the plane's navigation instruments.

Archaeologists have found two devices which they interpret as navigation instruments.

Possibly there was a misinterpretation of navigation instruments.