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Michael Moe

Some Questions regarding Charts and procedures

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Hi,

 

Lately i have come by some new procedures that i am not so familar with. Can anyone light up these for me ?

 

Thanks in advance

 

1. RNAV (GPS) and RNAV (RNP) The last one i have tried a couple of times in the T7 and in the NGX (Precision Approach)

2. GLS (For instance GLS RWY09 in KIAH) what is this ?

3. VGSI and RNAV GP not coincident on Approach charts

 

:-) :huh:

 

Thanks

 

Michael

 

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1. RNAV (GPS) and RNAV (RNP) The last one i have tried a couple of times in the T7 and in the NGX (Precision Approach)

 

RNAV GPS uses GPS as a form of RNAV (aRea NAV - basically, the ability to go from any location, directly to another)

RNAV RNP uses multiple forms of RNAV )any combination of: GPS, DME/DME, IRU/INS/IRS)

 

Since you didn't quite phrase it as a question, I'm not sure what you want to know here...

 

 

 


2. GLS (For instance GLS RWY09 in KIAH) what is this ?

 

Google is your friend, but, GLS means GPS-based ILS.  In other words, a GPS approach (using ground-based augmentation, like WAAS), that has positive vertical and horizontal deviation (and a narrowing approach corridor, like a LOC and GS do), offering an ILS-like set of minimums.

 

http://www.faa.gov/about/office_org/headquarters_offices/ato/service_units/techops/navservices/gnss/faq/laas/?print=go

 

 

 


3. VGSI and RNAV GP not coincident on Approach charts

 

Again, Google would've answered this rather quickly, but to save you having to search for it yourself:

 

VGSI - Visual Glide Slope Indicator

RNAV GP - RNAV Glide Path

"Not coincident" - not overlapping

 

...in other words, the PAPI/VASI/etc will indicate you're higher or lower than you should be when you follow the RNAV GP, so you will have to make a small path correction when you transition from instruments to visual references.

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Don't be embarrassed to ask basic questions. A good place to start is the AIM Airman Information Manual free from the FAA here: http://www.faa.gov/air_traffic/publications/http://www.faa.gov/air_traffic/publications/ and also from the FAA is the Instrument Flying Handbook at http://www.faa.gov/regulations_policies/handbooks_manuals/aviation/ all of which are free. Wikipedia is a pretty good source to for a lot of topics. I refer you to the FAA pilot manuals because they have been around a long time and are comprehensive.

 

Basics: You have visual and instrument approaches, each with their own set of rules. Instrument approaches are either precision or non-precision and by current definitions only the ILS is a precision approach because it provides a radio beam for verticle navigation. The GLS is a new type of GPS-based approach that provides minimums equivalent to Cat 1 ILS but is still a non-precision approach. RNP is also a type of GPS-based approach that is more stringent than the RNAV GPS-based approach because of crew training and equipment requirements.  When off-airway navigation first got started, it was done with on board computers that used existing VOR stations to created pseudo locations and the term RNAV was coined. Today, all RNAV is based on GPS and I guess that is part of the answer to #3 but I'd have to guess. I'll stop here before too much of my ignorance shows.

 

Hit the books, a ground school of several weeks is normally required before solo flight.

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Thanks for the answers.

 

I dont think i have any aircraft in my hangar for the GLS not that i need it. Still strange to me as a new none precision.

 

Edit. Great links with answers including which aircraft and the sls4000 precision system.

 

Now where do i find a GLS video? hmm YouTube maybe.....

 

 

Michael

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I dont think i have any aircraft in my hangar for the GLS not that i need it.

 

NGX uses IAN, which is good enough for GLS, I think...provided it's a GLS approach in the sim (the sim doesn't have WAAS, but the sim's GPS is "perfect" anyway, so WAAS isn't necessary i the sim).

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Thanks. I guess Navigraph also plays a role if they supports GLS. Will have a look at KIAH with the latest 07 build.

 

Michael

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Sorry to hijack the thread momentarily but I´ve had this question for a number of years now. I´ve been using IAN a lot when given Rnav approaches whilst flying online in Europe and USA. IAN is simply a great idea in my opinion, by making the transition from ILS to Rnav approaches that much easier and intuitive. At least to me, by simulating the ILS needles IAN keeps things simple and comfortable. I´d imagine most rw drivers out there so used to flying the ILS needles would feel the same way.

 

But how common is it, really? When given RNAV approaches do pilots use IAN in 737s that have this option installed? Do they need special training and/or authorization to use this "approach mode?"

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Sorry to hijack the thread momentarily but I´ve had this question for a number of years now. I´ve been using IAN a lot when given Rnav approaches whilst flying online in Europe and USA. IAN is simply a great idea in my opinion, by making the transition from ILS to Rnav approaches that much easier and intuitive. At least to me, by simulating the ILS needles IAN keeps things simple and comfortable. I´d imagine most rw drivers out there so used to flying the ILS needles would feel the same way.

 

But how common is it, really? When given RNAV approaches do pilots use IAN in 737s that have this option installed? Do they need special training and/or authorization to use this "approach mode?"

 

Put RNP (LNAV/VNAV) in these common questions as well.

 

Maybe USA is using it more than europe ?

 

Michael

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But how common is it, really? When given RNAV approaches do pilots use IAN in 737s that have this option installed? Do they need special training and/or authorization to use this "approach mode?"

 

[FAA-land]

Not very common, currently.  It's part of the reason for the BEBS concept I was working on at my last job.  Basically, there aren't enough aircraft in the fleet mix to justify moving from ILS to RNAV-based approaches, so they just don't issue them that often.

[/FAA-land]

 

...as for the rest of the questions, I have no idea.

 

 

 


Put RNP (LNAV/VNAV) in these common questions as well.
 
Maybe USA is using it more than europe ?

 

We might be using it more, or we might be using it less, but we're sure as heck not using it that often.

 

The FAA is actually still looking into an idea called Best Equipped - Best Served, where those with RNAV RNP capability would be allowed to jump ahead of people in the arrival stream to land, essentially.  Using RNAV RNP would greatly help the airspace issues we have in New York, and Chicago.  Additionally, it would help to allow higher throughput at PHL and SFO (utilizing offset RNP approaches alongside ILS approaches).

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Using RNAV RNP would greatly help the airspace issues we have in New York, and Chicago.

 

In the non-131 environment such as corporate aviation, RNAV terminal procedures are the preferred choice as long as they meet minimums. These procedures generally mean a lot less instructions (intrusion) from ATC and less time in queue - except at the primary dozen or so commercial hubs. As for the NY and Chicago messes and with all due respect to my collegue who is closer to ATC than I ever will be (ignoring that I one of my wives was a controller), when I comprare the progress made at Dallas and Houston I can't help but wondering if the problems is the turf battle between competing FAA facilities especially in NY. Look at Dallas for example, KDFW and KDAL as close as JFK and LGA and throw in a busy Navy base with two very busy non-131 airports and yet it works pretty smoothly on most days. Granted, DFW has lots of runway and even little Love is bigger that LGA.

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Hi,

 

I jumped inti this thread instead of opening another topic on the same matter, sorry.

 

I flew to Porto LPPR yesterday and noticed something I don't really understand.

 

There are a DVOR 35 and Locator 35 approach at this airport. Looking at the OCA for the straight-in approach, I noticed that the OCA of the DVOR (600ft) is lower than the one of the Locator (950ft).

 

What is the difference between both. I know that I tend to confuse Locator with Localizer as the frequency is in the same range but I guess there are different? What is the difference between the localizer wich is one part of the ILS and the locator?

 

Could somebody bring me a clear view of the three different kind of aid (DVOR, Locator, LLZ)?

Thanks

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LOC approach uses one of two components of the ILS system, which is the Localizer and it consists of two VHF beams projected from an antenna nearly as wide or wider than the runway located at the far end of your approach. This beam is very accurate. A locator, we have one in the USA at KDCA, is a beam projected from a single antenna that looks more like a NDB than Localizer, and I am not sure of it's accuracy but it is only good enough to get you to the right end of the airfield. The VOR (or DVOR, includes DME) is a completely different beast and its required navigational accuracy is +/- 6 degrees, which is a far cry from the azimuth accuracy obtained from a localizer but it is better than a locator; however, the DME does provide a very accurate distance measurement and the designers of this approach must have found that to be an advantage is computing the approach minimum.

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In the non-131 environment such as corporate aviation, RNAV terminal procedures are the preferred choice as long as they meet minimums. These procedures generally mean a lot less instructions (intrusion) from ATC and less time in queue - except at the primary dozen or so commercial hubs. As for the NY and Chicago messes and with all due respect to my collegue who is closer to ATC than I ever will be (ignoring that I one of my wives was a controller), when I comprare the progress made at Dallas and Houston I can't help but wondering if the problems is the turf battle between competing FAA facilities especially in NY. Look at Dallas for example, KDFW and KDAL as close as JFK and LGA and throw in a busy Navy base with two very busy non-131 airports and yet it works pretty smoothly on most days. Granted, DFW has lots of runway and even little Love is bigger that LGA.

 

I definitely agree with corporate preferring the RNAV stuff, but corporate traffic doesn't usually cause too much of an issue because they're usually using reliever airports, and fleet mix isn't usually an issue there (with the exception of TEB, perhaps).  Controllers and pilots alike usually have a lot less work to do to clear/fly the approach, so there's a distinct advantage.  The issue is that you really don't want to run multiple procedures to the same runways, and most all of the aircraft out there are at least ILS-equipped (into the fields where you have enough constant traffic for it to matter).  As such, the ILS is what gets assigned the vast majority of the time (into those fields).

 

Not sure what your friend does, but I was referencing work that I, personally, did with the FAA HQ and ATCSCC to address the issues, with N90, ZNY, and C90 representation in there (along with other facility TMU people simply as SMEs).  I don't recall DAL/DFW ever coming up, but looking at their facilities, it kinda makes sense.  If the ceiling drops, DFW can shift to their 13s to allow DAL to run the ILS to their 13s.  That's not an advantage N90 has.  If JFK goes 13s, then LGA is forced into 13 ops, which then puts EWR and TEB in a spot (because EWR can't reasonably use 11 for the fleet mix to the field, EWR has to share airspace with TEB to get aircraft in and out).  As far as military facilities go, those departures are managed as they come up, and down there, they all have runways in the same general direction without too much overlap.

 

 

 

 

 

 

EDIT:

Earlier, I wrote GPS-based ILS approach.  It's GBASS Landing System.  I'm really hoping I was distracted when I wrote that, because GPS-based ILS approach is probably one of the worst ways to describe it. (Thanks to Ryan for noticing that.)

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Hi Dan,

 

Thanks for that quick and clear answer! It clears up my misconception about the locator which I stupidly found closer to the localizer than the VOR because of its frequency range.

 

Now I understand the reason for the minima.

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For testing my primitive skills (still only a hobby pilot here :-) ) i desided to go for a RNAV17L in KDEN Denver.

 

First with Chart RNAV ( RNP) in LNAV/VNAV Path 0.30 DH377 and then a second try with Course related IAN (173) and FAC G/P. Worked like a charme.

 

Only Q remain is the 2 different RNAV Procedures. RNAV GPS and RNAV (RNP) for KDEN 17L. Both Procedures makes use of LNAV/VNAV.

 

I thought the RNAV"GPS"  procedures was for smaller planes without LNAV/VNAV.?

 

That leads to the Q. Is both procedures "acceptable" in the B737+B777 ?

 

 

Thanks

Michael :-)

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