RNP in GA?

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Richard Palm
Am I correct in thinking that a typical general aviation GPS receiver (such as a GNS 430W or a GTN 650) does not have RNP capability?
 
all gps do. its just not a nomeclature typically associated with ga applications. lpv guidance tolerances are rnp of .3 ,which all waas navigators are theoretically capable of attaining (aka ANP actual navigation performance).
 
AIM 1-2-2 discusses RNP.

1-2-2 d. discusses aircraft and airborne equipment eligibility for RNP operations. Pretty much says that it will be listed in the AFM.
 
AIM 1-2-2 discusses RNP.

1-2-2 d. discusses aircraft and airborne equipment eligibility for RNP operations. Pretty much says that it will be listed in the AFM.
Thanks. I started reading that AIM section before posting my question, but it was pretty thick going, and I gave up before I got to the end.

Unfortunately, the first opportunity I will have to read the AFM for the airplane I'm flying tomorrow morning will be during the preflight.
 
The GTNs with software 6.11 or newer can fly RNP AR approaches with RF legs. To be able to see and select them requires going into the system settings and enabling this feature.
 
all gps do. its just not a nomeclature typically associated with ga applications. lpv guidance tolerances are rnp of .3 ,which all waas navigators are theoretically capable of attaining (aka ANP actual navigation performance).
LNAV is RNP 0.30 in the final approach segment. LPV is not. It uses the ILS model. LP uses the localizer approach model.
 
The GTNs with software 6.11 or newer can fly RNP AR approaches with RF legs. To be able to see and select them requires going into the system settings and enabling this feature.
Not exactly. It can fly RF legs in RNP-1 procedures, such as KRNO RF-to ILS, (ILS or LOC X Runway 16R) and such as the KCRQ RNAV X Runway 24. It cannot fly RNP AR approaches, RF legs or not.
 
Not exactly. It can fly RF legs in RNP-1 procedures, such as KRNO RF-to ILS, and such as the KCRQ RNAV X Runway. It cannot fly RNP AR approaches, RF legs or not.

My bad—that’s what I trying to say but used the wrong verbiage. Garmin has a table somewhere which shows which of their systems are approved to do what.
 
I'm not sure about the Garmin stuff, but the FMSs that are capable of, for example, the RNAV (RNP) Z 10R (which is AUTHORIZATION REQUIRED) at KSFO http://155.178.201.160/d-tpp/1805/00375RRZ10R.PDF require a different database.
Aha! I overlooked the fact that the approach I was looking at also says authorization required, so it's a moot point. As the FAA page I looked at says, "Authorization Required (AR) procedures may only be conducted by aircrews meeting special training requirements...."
 

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Aha! I overlooked the fact that the approach I was looking at also says authorization required, so it's a moot point. As the FAA page I looked at says, "Authorization Required (AR) procedures may only be conducted by aircrews meeting special training requirements...."
Rule 1 for approach charts...read the title of the chart.

Rule 2 for approach charts...read the notes.
 
To clarify:

RNP is a generic term meaning "Required Navigation Performance" - basically the level of technical specifications your avionics and airplane meet.
GPS is just one type of RNP system.
The vast majority of light GA airplanes with an IFR-approved GPS can fly the RNAV (GPS) procedures that we are used to.
Some business jets, some airliners, and others, can fly RNAV (RNP) procedures. If you are eligible to fly these procedures, you will know it, because you will have received specialized training, and your aircraft will have to meet certain equipment requirements far above the average light GA airplane. AC 90-101A has the specifics.
 
Rule 1 for approach charts...read the title of the chart.

Rule 2 for approach charts...read the notes.
The title of the chart doesn't say anything about its being an "authorization required" procedure. However, I have no excuse for missing the all-caps large-font notation on the bottom!
 
The title of the chart doesn't say anything about its being an "authorization required" procedure. However, I have no excuse for missing the all-caps large-font notation on the bottom!
I'm just sayin' rule 2 is important, but you can't skip rule 1 on the way. ;)
 
My bad—that’s what I trying to say but used the wrong verbiage. Garmin has a table somewhere which shows which of their systems are approved to do what.
And, with RNP AR although you have the chart, the procedures aren't in your database.
 
Not exactly. It can fly RF legs in RNP-1 procedures, such as KRNO RF-to ILS, (ILS or LOC X Runway 16R)

RF means Radius to Fix, IE curved path, doesn't it? I see no such thing on that plate. What am I missing?

Sure is an interesting approach, though. Too bad it requires 230 knots at the IAF, I can't fly it!

Poking around, though, I'm guessing you meant the ILS Z 16R. That one has curves.

and such as the KCRQ RNAV X Runway 24. It cannot fly RNP AR approaches, RF legs or not.

Man, I wish we had some more approaches like this nearby so that I could try them out. How can I find the nearest one?

As it is, I decided to do a flight planning exercise from KCRQ to KRNO and plug it into the GTN simulator. That was kinda fun. Ended up with KCRQ CWARD2.SLI V8 PDZ J60 HEC JEDNA Q158 MYCAL Q162 KENNO.KENNO2 KLOCK and then the ILS Z 16R into KRNO as the route. /geek
 
Man, I wish we had some more approaches like this nearby so that I could try them out. How can I find the nearest one?
GYY and MDW aren't too far from you. They both have curved RNP's. Only ever seen 737's and bigger corporate jets do them though :)
 

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GYY and MDW aren't too far from you. They both have curved RNP's. Only ever seen 737's and bigger corporate jets do them though :)

"Procedure NA for wingspans greater than 136 feet." That's one I haven't seen before.

How does one fly an approach like this without using autopilot with GPSS? "Twist 10, turn 10" doesn't really work any more... And I'm pretty sure my non-GPSS KFC150 would end up outside the arc if I just sat there and dialed the HSI to the DTK of the moment.

Maybe following the magenta line would be OK in this instance? :D
 
"Procedure NA for wingspans greater than 136 feet." That's one I haven't seen before.

How does one fly an approach like this without using autopilot with GPSS? "Twist 10, turn 10" doesn't really work any more... And I'm pretty sure my non-GPSS KFC150 would end up outside the arc if I just sat there and dialed the HSI to the DTK of the moment.

Maybe following the magenta line would be OK in this instance? :D
Where it says on the plate authorization required, my understanding is your plane has to be appropriately equipped (whatever that is) and the autopilot is required to fly the approach. Twisting and turning not allowed. According to SWA and NBAA (I believe) the pilots have to have some sort of training/sign off for them as well. If you find out something definitive, let us know.
 
Where it says on the plate authorization required, my understanding is your plane has to be appropriately equipped (whatever that is) and the autopilot is required to fly the approach. Twisting and turning not allowed. According to SWA and NBAA (I believe) the pilots have to have some sort of training/sign off for them as well. If you find out something definitive, let us know.
That is correct...it takes about two years to get through the FAA authorization process from what I'm hearing, during which time the training program is implemented, etc.
 
That is correct...it takes about two years to get through the FAA authorization process from what I'm hearing, during which time the training program is implemented, etc.
Lots of training, assuming qualified airplane. With lots of money, perhaps as little as one year...perhaps.
 
We do the occasional RNP approach in the 737. It’s quite entertaining watching the autopilot/auto throttles descend and weave around the mountains in Medellin, Columbia. Sporty, too, if there’s convective weather.
 
I've flown a couple of RNP ARs, and yes I've taken the training and fly appropriately equipped aircraft for it. This is not coming to piston aviation anytime soon. It requires a highly automated aircraft, special crew training and a lot more. They are pretty cool to "fly," although really what you're doing is monitoring rather than flying, as the approaches must be flown on autopilot. What's really interesting to me are the "exotic" missed approach procedures. My favorite is the "alt hold" missed. If you have have to go missed early, you simply press alt hold and wait. That's it.
 
We do the occasional RNP approach in the 737. It’s quite entertaining watching the autopilot/auto throttles descend and weave around the mountains in Medellin, Columbia. Sporty, too, if there’s convective weather.
Yep. Once on the procedure deviation is not an option. That negates the concept of RNP and could be hazardous.
 
This is one of the more interesting RNP AR IAPs:
 

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