FAA Instrument Rating Airplane (IRA)Navigation SystemsMedium
What is the primary purpose of RAIM (Receiver Autonomous Integrity Monitoring) in a non-WAAS GPS receiver?
- ATo allow for the use of GPS in all phases of flight, including oceanic operations.
- BTo provide highly accurate vertical guidance for precision approaches.
- CTo detect and alert the pilot to GPS signal integrity anomalies.
- DTo augment GPS signals for improved accuracy and availability.
Show answer & explanationAnswer & explanation
Correct answer: C. To detect and alert the pilot to GPS signal integrity anomalies.
RAIM's primary function is to monitor the integrity of the GPS signals received by the aircraft and alert the pilot if the integrity is insufficient for the current phase of flight, particularly for instrument approach operations, in non-WAAS systems.
Why the other options are wrong
- A. While GPS is used in oceanic operations, RAIM specifically addresses signal integrity for navigation, not just general use.
- B. This is a function of WAAS, not RAIM.
- D. This describes the function of augmentation systems like WAAS or LAAS, not RAIM.
RAIM Purpose
RAIM (Receiver Autonomous Integrity Monitoring) is a technology in GPS receivers that assesses the integrity of GPS signals to ensure their reliability for navigation, especially during instrument flight.
- Detects faulty satellites or signal errors.
- Alerts pilots if integrity is insufficient for the current operation (e.g., approach).
- Essential for non-WAAS GPS approaches (LNAV).
Memory trick: RAIM is your GPS bodyguard.