RNAV Approach or RNP Approach how to read Chart?

[Michael Moe 495]

Can you give me an example? Perhaps you're confusing the ILS with the LOC information (which are usually provided on the same chart).

 

 

 

 

Sorry - again my bad. Looks like it is related to LOC+DME and GP inop on the ILS chart. Thanks Kyle  :rolleyes:

 

Michael Moe

[A_Pilot 5]

Wow this got nuts, and I'm finding that all the relevant information is here but is all tossed out and about! Couple things I found in here though that I didn't see fully addressed:

 

"RNP AR APCH this requires aditional aeroplane certification and pilot training. They may have lower RNP values than the standard RNP APCH value of 0.3, limitations of use should be published in your aircraft manual and training manual. "  

 

- the "AR" in there is Approval Required, and you typically find these in the restricted section of the hogwarts library your country's approach plates. Yes they do require aircraft certification, pilot training, and most importantly, legal approval. Just doing the training means nothing if your company doesn't have the legal thumbs up to do it. (Referred to in some countries as an Operations Specification - OPS SPEC)

 

The other thing I noticed is the bit of conversation about Non-precision and Precision-like nature of approaches. Now, I'm not 100% sure about what all the various nations consider precision or non-precision, but there's the important distinction about the behaviour of the gauge:

 

LNAV - deviation measured in (constant) distance. Proximity to the next waypoint on final doesn't affect sensitivity of the gauge. Full deflection means you're 0.3 (or as specified) off course at whatever point you're off-course.

 

LNAV/VNAV - same LNAV as above, but adding either a barometric based glideslope (Baro-VNAV) or satallite based  glideslope (WAAS in North America)

 

LP & LPV - "Precision-like" - deviation measured in degrees - the closer you get to the runway the more sensitive the gauge is, like an ILS. This doesn't mean it is a precision approach in all countries, it just behaves like one. Mins will be in the 250' or lower AGL range, like an ILS. Full deflection means you're however many degrees off-course as your gauge is capable of telling you. 

[Driver170 42]

Nice reply luc

 

Can you explain why certain RNAV app in the EU have only LNAV minima? And is it correct you need to temp correct these minima below 0c ?

 

As for LNAV/VNAV you are allowed to fly this app aslong as the temp is above whats on the chart ie NA TEMP BELOW -15c

[A_Pilot 5]

Nice reply luc

 

Can you explain why certain RNAV app in the EU have only LNAV minima? And is it correct you need to temp correct these minima below 0c ?

 

As for LNAV/VNAV you are allowed to fly this app aslong as the temp is above whats on the chart ie NA TEMP BELOW -15c

 

LNAV is the "easiest" to certify because the final approach segment altitude is the highest of all the GPS approaches.

 

An approach will have only the minima that have been certified for the airport. It costs money to have an approach designed and certified. The lower the mins, the more complex the design process in certain areas. Operational need decides what airports get what treatment. Finally, some airports just can't handle the lower minima for approaches because of obstacle clearance requirements (Alps, North American Rockies, the entirety of Nepal).

 

Based on what's been assessed, you may find temperature restrictions due to the limitations of the certification process for the country. I'm also guessing that a -15 limit on your approach might remove the need for a cold weather correction (the approach may be guaranteed obstacle clearance down to that limit), but that will be explicitly listed on the plate or in the general section of your country's documentation.

 

However, in Canada with our Rocky Mountains you find no such temperature limitations because cold weather is par for the course here, and all operators are expected to know how to fly

 

 

Cold weather corrections are right up my Canadian alley! Yes, below 0 you're required to add a cold weather correction to all your altitudes (some countries anything higher than 3000 AGL is exempt): DH, MDA, FAF, Procedure turn,MSA 25, 100nm safe, etc) If it's on the plate, correct it. This makes for charts with a lot of pencil scratches on them at first, and every northern Canadian pilot has the correction table taped to their clipboard it's used so often. Vector altitudes are already corrected for you.

 

The Canadian cold weather correction chart gives up after -50. This relates nicely with the -40 limit on many engines as a starting temperature because your oil is too thick and you'll break the starter. 

 

If you've never experienced -40 before, don't try it. It hurts to exist at that temperature

[Driver170 42]

Yeh very true not only Boeing and airbuses use those airports you'll have a variety of acft so not all can use LNAV/VNAV mins.

 

And like you say, all depends on the airport !

[scandinavian13 5,192]

 

 

- the "AR" in there is Approval Required, and you typically find these in the restricted section of the hogwarts library your country's approach plates. Yes they do require aircraft certification, pilot training, and most importantly, legal approval. Just doing the training means nothing if your company doesn't have the legal thumbs up to do it. (Referred to in some countries as an Operations Specification - OPS SPEC)

 

I mentioned this in post #2, though I didn't go into as much detail. We also don't cordon them off in a different section. We put them logically with the rest of the charts for that airport.

 

 

 

LNAV - deviation measured in (constant) distance. Proximity to the next waypoint on final doesn't affect sensitivity of the gauge. Full deflection means you're 0.3 (or as specified) off course at whatever point you're off-course.
 
LNAV/VNAV - same LNAV as above, but adding either a barometric based glideslope (Baro-VNAV) or satallite based  glideslope (WAAS in North America)
 
LP & LPV - "Precision-like" - deviation measured in degrees - the closer you get to the runway the more sensitive the gauge is, like an ILS. This doesn't mean it is a precision approach in all countries, it just behaves like one. Mins will be in the 250' or lower AGL range, like an ILS. Full deflection means you're however many degrees off-course as your gauge is capable of telling you. 

 

This is a good explanation of it all.

 

Side note: LP is not precision-like. I'm sure you were just going for explaining the narrowing course concept, but LP is simply LOC-like, and LOC is definitely not precision. Just wanted to make sure that's clear for others coming through here.

 

 

 

LNAV is the "easiest" to certify because the final approach segment altitude is the highest of all the GPS approaches.
 
An approach will have only the minima that have been certified for the airport. It costs money to have an approach designed and certified. The lower the mins, the more complex the design process in certain areas.

 

This isn't always the case, but to discuss that would be to dive pretty deep into the whole process, and wouldn't really help the discussion here, so I'll just mention that there are exceptions.

 

 

 

Yeh very true not only Boeing and airbuses use those airports you'll have a variety of acft so not all can use LNAV/VNAV mins.

 

You can fly an LNAV/VNAV approach in a Spam Can equipped with a Garmin 530, actually. Heck, the Spam Can I flew into PHL a few months ago had WAAS, so I could've flown an LPV if I needed to. In fact, the plane makes everything so easy that I specifically avoided it when doing any training. I went from that (a 172S with a loaded G1000) to a 172M a few weeks ago and fumbled around a bit with an iPad since all the frequencies were not readily available on a flat screen display right in front of me.

 

Don't get hung up on the fact that there are MCP buttons labeled LNAV/VNAV in Boeing/Airbus, and not in other planes. The LNAV/VNAV really boils down to the concept that there is calculated guidance being provided.

[Driver170 42]

Found this but think its FAA! Does it matter

 

 

http://www.askacfi.com/1585/differences-between-lnavvnav-and-lnav-minima-on-a-gps-instrument-approach.htm

Great photo kyle

[scandinavian13 5,192]

 

 

Found this but think its FAA! Does it matter

 

Not really. It just goes about explaining what's already been discussed here, but in a less clear way.

 

 

 

Great photo kyle

 

Thanks. Really wish I took it with my real camera. My phone gets (understandably) grainy in low light. I actually dumped a bunch of my flight bag (to include my SLR) back into my car when I saw how much extra stuff the ladies I was flying up to PHL had with them. Then again, it was a fashion show, so some of it was to be expected...

[Driver170 42]

 

 

 
Thanks. Really wish I took it with my real camera. My phone gets (understandably) grainy in low light. I actually dumped a bunch of my flight bag (to include my SLR) back into my car when I saw how much extra stuff the ladies I was flying up to PHL had with them. Then again, it was a fashion show, so some of it was to be expected...

 

surely you will have alot of hours ? go for your commercial 

[scandinavian13 5,192]

surely you will have alot of hours ? go for your commercial 

 

Interestingly enough...looking at my log book, all I need to do is kill some time in a complex aircraft and I'm pretty much good to go on the commercial pilot cert.

 

I'll definitely do it, but I will probably never fly for the airlines. I make a lot more doing what I do for the FAA, and I don't have to deal with a bunch of pilots around me with shiny jet syndrome, or depressed outlooks on the future of aviation.

[Driver170 42]

Well atleast you have flown! So whats all doom and gloom with the aviation for the future?

 

I know i make more than the JNRs with certain airlines at the UK! But that doesn't mean i wouldn't switch over lol

[A_Pilot 5]

 

 

Side note: LP is not precision-like. I'm sure you were just going for explaining the narrowing course concept, but LP is simply LOC-like, and LOC is definitely not precision. Just wanted to make sure that's clear for others coming through here.

 

Good clarification, I meant "precision-like" in that is gets more sensitive the closer you get to it. But by all means the LP is the GPS equivalent of a LOC

 

 

I don't have to deal with a bunch of pilots around me with shiny jet syndrome, or depressed outlooks on the future of aviation.

 

The double-whammy I'm finding out about as a guy trying to get into the industry with no connections and no insider knowledge. 

[scandinavian13 5,192]

 

 

Good clarification, I meant "precision-like" in that is gets more sensitive the closer you get to it. But by all means the LP is the GPS equivalent of a LOC

 

Yeah. I figured that's what you were getting at. Just wanted to be sure.

 

 

 

The double-whammy I'm finding out about as a guy trying to get into the industry with no connections and no insider knowledge. 

 

Rough, isn't it? I remember when I was still at Virginia Tech looking at graduating and going to a pilot academy. The people I came across in aviation forums were just so negative, and not very supportive. I learned to ignore most of them. In many ways, they're not here for the right reasons. For me, all I could think is "if you hate it so much then get out of my way..."

[A_Pilot 5]

 

 

if you hate it so much then get out of my way...

 

Should make that my life slogan. 

 

Well, that's why I have this flightsim of mine. At least for now I have access to good full-cockpit sims at the company I work for, and regular company-sponsored Multi-IFR training (in the sims, but it works) Keeps me ready for that phonecall

[Akila 39]

out of all this

RNAV (GNSS) with LNAV only (not LNAV/VNAV) on a chart (ICAO Airports/charts - outside the US)  is considured RNP or not?