Definition
The contribution to total navigation system error that comes from the avionics receiver itself, expressed as how closely the receiver can determine the aircraft's position from the navigation signals it processes. For RNAV operations, receiver accuracy is one of three components combined to establish the system's overall cross-track error tolerance, alongside signal-in-space error and flight technical error.
Plain English
How precisely the navigation box in the aircraft can figure out where the aircraft actually is, based on the signals it receives. It is one piece of the total error budget that determines how wide the protected airspace around a route needs to be.
Context Anchor
Seen in instrument procedure design and obstacle clearance discussions, especially when explaining how much protected airspace is built around an instrument route.
Why Pilots Care
Lower receiver accuracy requires larger obstacle clearance areas to maintain safety margins.
Analogy
A bathroom scale may be a pound or two off even when it works normally. Receiver accuracy is the navigation version of that allowed small error.
Intuition Check
Do not read accuracy here as meaning “perfect.” In this context, receiver accuracy means the known amount of possible error allowed for the aircraft’s navigation receiver.
Example Sentence 1
The width of the RNAV obstacle clearance area is calculated using receiver accuracy, signal-in-space error, and flight technical error combined.
Example Sentence 2
If receiver accuracy degrades, the pilot must fly a route with wider protected airspace.