Hello I am trying to learn how to properly conduct an RNP approach. The approach I am using is the KMIA 12 RNP. Using LNAV and VNAV I get the pink triangle and seem to intercept properly at GLRIA. From there it goes down hill rapidly. I cannot get the aircraft to descend and properly track the glide path. Does this approach require hand flying only or can it be done using all of the technology? Crossing GLRIA at 3000 I keep waiting for VNAV to start the descent down to 2000. I have my altitude set to 2000. Any help would be appreciated. If someone flies this approach I would be interested in how it was done. ThanksDon

Make sure you still have the VNAV PATH indicated and that you have a Top of Descent on your map or V-Track indication on the PFD. If it won't descend, make sure you know why by looking at the Flight Mode Annunciator. It can be flown with the A/P.

Do you have a chart for this approach? Maybe posting a link to it will let you get help from more people who might not be familiar with the procedure otherwise.

With my nifty iPad software I found a public RNAV to 12, but no RNP. The procedures should be mostly the same for you, but is it the RNAV12 approach?

u can utilize the alt inv button

Here is the link to the KMIA RNP RWY 12 approach. I use AIRNAV.comhttp://204.108.4.16/d-tpp/1109/00257RRY12.PDF I also use RC4. I love this program and have used it for at least 3 years. At some point I leave the vectoring and tell RC4 I want the full approach.If I use LNAV and VNAV and cross the IAF at the correct altitude and have the MCP altitude set to a lower altitude I would think the aircraft would descend with the AT and AP engaged and fly the approach.I did look in the FCOM2 and did not see much about how to do these approaches. If there are RNP guru's out there I would appreciate your help. I do something similiar to this with the Mustang when doing a WAAS approach and it works great.

Don't know if this helps but I set up to use LNAV/VNAV (RNP) for a visual approach and it intercepted the course but it held to my IAF altitude of 3000 feet even though I had MDA of 500 set in ALT. When I pressed the ALT INV button everything immediately began operating correctly.

I will try this. KLAS KPSP RNP RNAV Y 13R. Thanks

If everything is set correctly and programmed by PMDG correctly, you shouldn't need to use alt intervention. Make sure you're in VNAV PATH before you start the procedure.

I did another KLAS KPSP flight doing the RNAV Y 13R approach. I have to say PMDG did an excellent job on these approaches. This approach worked perfectly. There are 2 things that helped me. One was to do an advanced search on "FAC" in FCOM2 . Make it case sensitive and whole word only. This will give you about 50 hits with good information. On one of the pages the procedure called for the "APP" button to be pressed. This is so important as it was the one item that allowed me to shoot the approach correctly. I flew the approach and the last 2-3 miles I hand flew but could have done a coupled approach all the way to touchdown. Hope this helps anyone who is interested in IAN or RNP. Don

I did another KLAS KPSP flight doing the RNAV Y 13R approach. I have to say PMDG did an excellent job on these approaches. This approach worked perfectly. There are 2 things that helped me. One was to do an advanced search on "FAC" in FCOM2 . Make it case sensitive and whole word only. This will give you about 50 hits with good information. On one of the pages the procedure called for the "APP" button to be pressed. This is so important as it was the one item that allowed me to shoot the approach correctly. I flew the approach and the last 2-3 miles I hand flew but could have done a coupled approach all the way to touchdown. Hope this helps anyone who is interested in IAN or RNP. Don

See this post... http://forum.avsim.net/topic/347337-successful-ian-approach/ DJ