Local-area augmentation system

A receiver on an aircraft uses this information to correct GPS signals, which then provides a standard instrument landing system (ILS)-style display to use while flying a precision approach.

The FAA has stopped using the term LAAS and has transitioned to the International Civil Aviation Organization (ICAO) terminology of ground-based augmentation system (GBAS).

[1] While the FAA has indefinitely delayed plans for federal GBAS acquisition, the system can be purchased by airports and installed as a Non-Federal navigation aid.

The history of these standards can trace back to efforts in the United States by the Federal Aviation Administration to develop a Local Area Augmentation System (LAAS).

The monitoring enables the GBAS to detect anomalous GPS satellite behavior and alert users in a time frame appropriate for aviation uses.

The GBAS provides corrections to the GPS signals with a resulting improvement in accuracy sufficient to support aircraft precision approach operations.

Honeywell has developed a Non-Federal CAT-1 GBAS which received system design approval from the Federal Aviation Administration (FAA) in September 2009 [1].

LAAS utilizes a Time Division Multiple Access (TDMA) technology in servicing the entire airport with a single frequency allocation.

Aircraft equipped with LAAS technology can utilize curved or complex approaches such that they could be flown on to avoid obstacles or to decrease noise levels in areas surrounding an airport.

This technology shares similar characteristics with the older Microwave landing system (MLS) Approaches, commonly seen in Europe.

The GBAS precision approaches is one of the investment programs that provide solution to "increase flexibility in the terminal environment" in the NextGen implementation plan.