Hello PMDG people.I would like that somebody explain me please, what RNP and ANP in the navigation display mean. It is in the bottom of the ND.Thank you.Jorge Escobar.

Hi Jorge,ANP stands for "Actual Navigational Performance". It's a number that is calculated by the aircraft systems (and only the aircraft onboard systems - no ground nav aids are used for calculation) indicating how reliable the aircraft position is at the moment. RNP stands for "Required Navigational Performance". This number indicates the required reliability of the aircraft position. Both numbers change during the flight. RNP should always be < ANP. ANP/RNP are necessary parameters for flying RNAV approaches e.g.!Hope that help a bit.Frederik

Required and Actual Navigation Performance:http://forum.avsim.net/topic/327118-writeup-of-rnp/http://en.wikipedia.org/wiki/Required_Navigation_Performance

.... RNP should always be < ANP. ANP/RNP are necessary parameters for flying RNAV approaches e.g.!...

I'm sure its just a typo, but I'll mention it for clarity anyways. RNP should always be > than ANP. If its lower then the plane wouldnt be allowed to fly an RNP approach

Just wondering, how do RNP approaches fit in with WAAS approaches? I understand the former nav method is derived from IRS, the later from GPS, but are there seperate approach plates for each?

I'm sure its just a typo, but I'll mention it for clarity anyways. RNP should always be > than ANP. If its lower then the plane wouldnt be allowed to fly an RNP approach

You're right. Sorry 'bout that!Frederik

Thanks for your replays. Now I know what it means. If you know any video about any RNAV approach plese give me the link.

Pretty nice rnp approach.http://www.youtube.com/watch?v=AHF9rPWFXzw

Just wondering, how do RNP approaches fit in with WAAS approaches? I understand the former nav method is derived from IRS, the later from GPS, but are there seperate approach plates for each?

They don't fit at all. These are two separate worlds.First of all it is incorrect to say RNP is derived from IRS, RNP requires pretty advanced FMS with GPS capability. You can't really fly any RNP these days without GPS.The way it developed by historical and financial reasons - WAAS found its place in smaller aircraft, RNP is what big boys use if they need it.

It's a number that is calculated by the aircraft systems (and only the aircraft onboard systems - no ground nav aids are used for calculation)

It actually relates to cumulative error of the IRS (another way of measuring average IRS drift, remembering that the FMS position is an average of the positions reported by all two/three IRS units).

First of all it is incorrect to say RNP is derived from IRS, RNP requires pretty advanced FMS with GPS capability. You can't really fly any RNP these days without GPS.

You can fly RNAV without GPS (GPS/IRS combos are called GNS) - many airlines do it every day. RNP relates to the REQUIRED minimum accuracy of any given RNAV certified equipment that must be met in order to use it.Best regards,Robin.

Thanks for your replays. Now I know what it means. If you know any video about any RNAV approach plese give me the link.

Here is a video of a visual app to Townsville (YBTL) rwy 19, but following an RNP approach procedure, viewed through the HUDTB

Here is a video of a visual app to Townsville (YBTL) rwy 19, but following an RNP approach procedure, viewed through the HUDTB

sorry, here is the link

TB