Hey fellow simmers, I flew the infamous RNAV approach into KPSP. (http://aeronav.faa.gov/d-tpp/1108/00545RRY13R.PDF) So everything went perfectly until I all of a sudden got an impossible descent warning on my FMC almost right before I turned final (around 3700 feet). The message wasn't there anytime before the flight. I've also set my flaps down in time and made sure that I was on speed. I double checked the FMC with the chart before the flight and everything matched. I also made sure that I set the RNP value to .30 before the T/D. It's frustrating because I absolutely loved the approach but was unsuccessful at the end. Any help would be greatly appreciated.

Did you read prior threads (before 737NGX release)? It was clearly stated that RNP approaches will not be supported in the first release. You can go and find Robert Randazzo's precise statement on the subject.

Did you read prior threads (before 737NGX release)? It was clearly stated that RNP approaches will not be supported in the first release. You can go and find Robert Randazzo's precise statement on the subject.

My apologies. I read a conflicting thread just a few hours back and I thought it was indeed modeled.

Understood.

I double checked the FMC with the chart before the flight and everything matched.

Well, this should tell you right away it would not work. No approach is ever "keyed-in" waypoint by waypoint from the keyboard. You load the whole approach from available list of approaches. Otherwise FMC treats it simply as collection of enroute waypoints. You do not get approach this way. But it must have looked very weird to your FMC - strange route.

Understood. Well, this should tell you right away it would not work. No approach is ever "keyed-in" from the keyboard. You load the whole approach from available list of approaches. Otherwise FMC treats it simply as collection of enroute waypoints. You do not get approach this way. But it looked no doubt very weird to your FMC - strange route.

That's what I did. It actually shows the RNAV approach can be selected. I didn't end up keying anything actually.

Hmm, I was under the impression that RNP approaches were functioning EXCEPT those which require a radius to fix (RF) which are being planned for the service pack.. Correct me if I'm wrong?

That's what I did. It actually shows the RNAV approach can be selected. I didn't end up keying anything actually.

Sorry, I thought you keyed it in.But FMC still must have additional 'RNP software' to be able to execute it.

Hmm, I was under the impression that RNP approaches were functioning EXCEPT those which require a radius to fix (RF) which are being planned for the service pack.. Correct me if I'm wrong?

You could it be right. Try one.

Hmm, I was under the impression that RNP approaches were functioning EXCEPT those which require a radius to fix (RF) which are being planned for the service pack.. Correct me if I'm wrong?

Yup. That approach did need an RF.Also, Ryan stated that RNP approaches will be covered in the later tutorial in Tutorial 1.

Hmm, I was under the impression that RNP approaches were functioning EXCEPT those which require a radius to fix (RF) which are being planned for the service pack.. Correct me if I'm wrong?

This is correct.

RNP is modeled as per the features on the purchase page. But yes the procedure must be loaded as if you where loading a SID/STAR

Yes and it seems to be RNP 0.3 only, I flew one into FLL without issue, very nice simulation watching the RNP required ratcheting down from 2 to 0.3. And if you didn't already know this you can do an LNAV/VNAV or fly a LNAV/LPV you will see FAC and GP arm on the flight mode annunciators, really cool. VRTodd

If it was RF capable, how would I set up the radial to fix point?

If it was RF capable, how would I set up the radial to fix point?

You wouldn't have to set up any radials at your end. The flight software would handle all this stuff. I presume if you looked at the data representation for this approach all the info about radials is there and software knows how to parse it and use it.