GPS Navigation Flashcards
How many satellites are required for a GPS system to determine latitude and longitude?
At least three satellites.
How many satellites are required for a GPS system to determine latitude, longitude, and altitude?
At least four satellites.
What is RAIM and what does it provide for GPS navigation?
RAIM is Receiver Autonomous Integrity Monitoring, used to cross-check GPS position using a fifth satellite.
What is WAAS and how does it improve GPS accuracy?
WAAS is the Wide Area Augmentation System, which uses ground stations to enhance GPS signal accuracy, allowing vertical guidance.
What is the difference between TSO-C129 and TSO-C145 GPS units?
TSO-C129 units are older, unaugmented GPS systems requiring RAIM, while TSO-C145 units are WAAS-enabled and support vertical guidance.
What does LPV stand for in GPS approaches, and what does it provide?
LPV stands for Localizer Performance with Vertical guidance, providing both lateral and vertical guidance, similar to an ILS.
What is LNAV/VNAV in GPS approaches?
LNAV/VNAV provides both lateral and vertical guidance but uses external sources like baro-assist for vertical guidance.
What is the difference between LP and LPV approaches?
LP provides only lateral guidance, while LPV provides both lateral and vertical guidance.
What does LNAV provide in a GPS approach?
LNAV provides basic lateral navigation only, terminating at a minimum descent altitude.
What is LNAV+V and how is it different from LNAV?
LNAV+V uses WAAS to provide advisory vertical guidance but is not an official vertical guidance approach.
What does APV stand for in GPS approaches?
APV stands for Approach with Vertical Guidance, providing lateral and vertical guidance but is not classified as a precision approach.
What does RNP stand for, and what does it measure in GPS systems?
RNP stands for Required Navigation Performance, measuring a system’s lateral accuracy and ensuring performance standards are met.
What is the lateral accuracy requirement for RNP during the final approach phase?
0.3NM in the final approach phase.
