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RNAV and RNP

Asked by: 5815 views , , ,
FAA Regulations, General Aviation, Instrument Rating, Student Pilot

I have been trying to go over RNP with the various ACs and supplements on RNP and I am still confused and have questions that someone may be able to clear up. 

First, what I think I know about RNP, RNP is a section off of PBN. As is RNAV, RNAV is a less accurate source for navigation than RNP. Basically RNP enhances the accuracy of your course during a flight to be more precise on centerline of your course. 

That's what I think I know about it, I'm not sure if that is correct at all.

Now the questions,

How does WAAS help with RNP, I know it helps with RNAV by improving accuracy up to 10ft precision, but what does it do with RNP?

I read something that said RNP had integrity monitory while GPS didn't have to have that. Is this where RAIM comes into play? 

So there are different levels of RNP service? RNP 0.3 (approach) RNP 1.0 (Terminal, arrival/departure), RNP 2.0 (en-route). Now these 0.3, 1.0, and 2.0 are the guaranteed distances to be from the centerline (left or right) of your course (during that stage of flight) 95% of the time?

If so... 

On the AOPA course GPS for IFR operations it says for Terminal mode the course width is 2nm, Enroute mode it says course width is 10nm and Approach mode is 0.3 (which makes sense based off of the RNP 0.3 above). My question now being, why is the enroute mode 10nm if the RNP is 2.0 nm of center line and Terminal mode 1.0, if the course width above is 2nm? 

Any insight would be greatly appreciated.

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1 Answers



  1. John D Collins on Jan 12, 2017

    Here is what the FAA states:

    Required Navigation Performance (RNP) is similar to Area Navigation (RNAV); but, RNP requires on-board navigation performance monitoring and alerting capability to ensure that the aircraft stays within a specific containment area.

    In other words, there is no accuracy difference between RNAV and RNP specifications of the same value, RNAV 1.0 and RNP 1.0 are equally accurate. The difference is that with the RNP navigation specification, on-board navigation performance monitoring and alerting capability is required.

    RNAV 2 is essentially the same as what is used for airways, T, and Q routes. The primary protected airspace is two times the RNAV value, so +/- 4 NM.The pilot is supposed to remain within the RNAV specification 95% of the time and if their deviation is outside of the specification, they must immediately begin a correction to the center line of the course.

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