Welcome Guest. Sign in or Signup

1 Answers

RNAV and RNP

Asked by: 5099 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.

Ace Any FAA Written Test!
Actual FAA Questions / Free Lifetime Updates
The best explanations in the business
Fast, efficient study.
Pass Your Checkride With Confidence!
FAA Practical Test prep that reflects actual checkrides.
Any checkride: Airplane, Helicopter, Glider, etc.
Written and maintained by actual pilot examiners and master CFIs.
The World's Most Trusted eLogbook
Be Organized, Current, Professional, and Safe.
Highly customizable - for student pilots through pros.
Free Transition Service for users of other eLogs.
Our sincere thanks to pilots such as yourself who support AskACFI while helping themselves by using the awesome PC, Mac, iPhone/iPad, and Android aviation apps of our sponsors.

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.

    +1 Votes Thumb up 1 Votes Thumb down 0 Votes


Answer Question

Our sincere thanks to all who contribute constructively to this forum in answering flight training questions. If you are a flight instructor or represent a flight school / FBO offering flight instruction, you are welcome to include links to your site and related contact information as it pertains to offering local flight instruction in a specific geographic area. Additionally, direct links to FAA and related official government sources of information are welcome. However we thank you for your understanding that links to other sites or text that may be construed as explicit or implicit advertising of other business, sites, or goods/services are not permitted even if such links nominally are relevant to the question asked.