Definition
A signal transmitted on a VHF radio frequency from a Local Area Augmentation System (LAAS) ground station to nearby aircraft, carrying GPS correction data and approach path information used to fly precision approaches.
Plain English
A radio signal sent out from the airport on a VHF frequency that tells your aircraft how to correct GPS errors and follow the approach path accurately.
Context Anchor
Seen in Local Area Augmentation System approach discussions, where the aircraft receives runway-specific landing guidance from a ground station near the airport.
Derivation
VHF stands for Very High Frequency, the radio band (30–300 MHz) already used for aircraft communications and navigation. 'Data broadcast' simply means information transmitted outward to any receiver in range, rather than a two-way conversation. Together: a one-way information signal sent over the same kind of radio band pilots already use every flight.
Why Pilots Care
It supplies the real-time corrections that allow GPS to support Category I, II, and III approaches with the accuracy and integrity required for safe low-visibility landings.
Analogy
Think of it like a local radio station for landing data. Instead of sending music or voice, the station sends correction and safety information for aircraft using that airport’s approach.
Intuition Check
Do not think of this as a voice radio call or a two-way data conversation. In this context, broadcast means a one-way radio transmission from the ground station to aircraft in range.
Example Sentence 1
After tuning the approach, the GPS receiver locked onto the VHF data broadcast from the LAAS ground station and displayed the precision approach guidance.
Example Sentence 2
Loss of the VHF data broadcast signal caused the aircraft to revert from GBAS guidance to an ILS backup.