Definition
An early long-range radio navigation system that determined an aircraft's position by measuring the time difference between pulsed signals received from pairs of ground-based transmitting stations. LORAN A operated in the 1.75 to 1.95 MHz frequency band and was the first operational version of the LORAN family, deployed during World War II and used for marine and aviation navigation until it was phased out in favor of the more accurate LORAN C.
Plain English
An older radio navigation system that worked out where you were by timing how long signals took to reach you from two different ground stations. It was the first version of LORAN and has since been replaced by newer systems.
Context Anchor
Seen in older avionics references, maintenance manuals, and historical navigation discussions.
Derivation
LORAN comes from LOng RAnge Navigation. The 'A' simply marks it as the first version of the system. Later versions (LORAN B and LORAN C) refined the technique with better accuracy and different frequencies.
Why Pilots Care
It gave pilots a reliable way to navigate over oceans and remote areas before GPS existed.
Intuition Check
The “A” in LORAN A is not an accuracy grade. It names a version of the LORAN navigation system.
Example Sentence 1
The vintage aircraft's avionics bay still contained a LORAN A receiver, though it had been decommissioned years before.
Example Sentence 2
Technicians serviced the LORAN A unit as part of the aircraft's routine navigation equipment checks.