FAA Instrument Rating Airplane (IRA)Navigation SystemsHard
A pilot is flying an aircraft equipped with a GPS receiver that is TSO-C129a certified. This receiver does not have WAAS capability. What is the limitation regarding its use for IFR en route and terminal operations?
- AIt can be used for IFR en route and terminal operations only if RAIM is available and continuously monitored.
- BIt can be used for IFR en route and terminal operations without any restrictions.
- CIt can be used for IFR en route operations, but not for terminal operations unless an alternate means of navigation is also available.
- DIt can be used for IFR en route and terminal operations, but must be paired with an operational VOR for primary navigation.
Show answer & explanationAnswer & explanation
Correct answer: A. It can be used for IFR en route and terminal operations only if RAIM is available and continuously monitored.
TSO-C129a GPS receivers without WAAS require RAIM (Receiver Autonomous Integrity Monitoring) to be available and continuously monitored for IFR en route and terminal operations. If RAIM is lost, the pilot must revert to an alternate means of navigation. This ensures integrity for non-WAAS systems.
Why the other options are wrong
- B. Non-WAAS TSO-C129a GPS has limitations, primarily requiring RAIM.
- C. It can be used for both en route and terminal operations, provided RAIM is available; the restriction is not on terminal operations specifically but on RAIM availability.
- D. While VORs are often used as backup, the primary limitation for a TSO-C129a GPS is RAIM, not a mandatory pairing with VOR for primary navigation.
TSO-C129a (Non-WAAS) GPS Limitations
For IFR en route and terminal operations, TSO-C129a non-WAAS GPS receivers require continuous RAIM availability and monitoring to ensure navigation integrity.
- Applies to non-WAAS GPS units.
- Requires RAIM for integrity.
- RAIM prediction and monitoring are critical.
Memory trick: No WAAS? RAIM is your AIM!