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pwm2txlhopper
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Question about RNAV Approaches and who uses them.

Wed Jun 06, 2018 2:01 pm

When I learned to fly during the late 1990's, GPS navigation and glass cockpits were for a lucky few. Therefore, my knowledge of GPS navigation is not very advanced, as I haven't flown in almost two decades.

My question is about RNAV Approaches. How common are these used today? Also, while searching YouTube videos of RNAV Approaches being perforformed, I'm coming across almost no videos of commercial airlines sized jets doing RNAV landings. It's mostly small G.A. planes.0

Is RNAV something the big boys don't use? Or at least during IMC landings? I don't think I've ever heard my local Tower clear a commercial airline flight for an RNAV approach.

Also, do modern day airliners still actually tune to VOR's VHF signals? Or, does the GPS just display the VOR as a digital navigation fix on the screen?
 
LH707330
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Re: Question about RNAV Approaches and who uses them.

Wed Jun 06, 2018 2:16 pm

Most major fields already have an ILS, so there's not as much need to use an RNAV approach instead, whereas the smaller GA fields that I fly to mostly don't have an ILS, so we use RNAV approaches. Furthermore, most RNAV approaches that I've flown have higher minima than ILS, so in actual IMC you're better off sticking with the ILS.

One downside to RNAV approaches is that the planes fly the same track instead of being vectored to final over a wider area, which concentrates the noise. Google "RNAV noise complaints" and you'll get a few hits. One simple fix for this would be to add a variety of different IAFs to popular RNAV routes to spread them out again.
 
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Starlionblue
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Re: Question about RNAV Approaches and who uses them.

Wed Jun 06, 2018 2:24 pm

If there is an ILS we normally use that but we use RNAV approaches reasonably often. Some places don't have ILS at all (e.g. Cebu-Mactan), or only an ILS on some runways. Melbourne, for example, has ILS on 16 and 27, but for performance reasons we often require 34, so we'll do the RNAV.

One of the differences is no autoland so hand flying is mandatory below minima, but in the not too distant future it is likely non-ILS approaches will be autoland-able. ILS is an expensive piece of kit to maintain and RNAV allows the airport big savings since there's no ground equipment that needs maintenance and periodic calibration. On the other hand, a place like CDG needs ILS due to frequently poor visibility. Whether you can do away with an ILS very much depends on prevailing weather conditions.

It's really no big deal in modern airliners. Even on the 330, which is a 25 year old design, you get vertical guidance if there's a published VNAV profile.

On the 350, you get "ILS-like" guidance with the "xLS" concept. Looks and feels pretty much like an ILS except the vertical and horizontal deviation scale have double diamonds while an ILS has single diamonds. (For that matter, the 350 gives "ILS-like" guidance in both lateral and vertical on VOR and LOC approaches as well). We can also use RNP-AR approaches, which is like RNAV but with requirements for onboard monitoring and alerting. However, I've only seen those in the sim as yet.

Here's a good presentation from Airbus on the xLS concept implemented in the 350. http://www.ae-expo.eu/wp-content/uploads/2016/04/Frederic-Belloir-Airbus-xLS-concept.pdf

Airliners still tune VORs. This is done automatically by the FM, with DME and VOR signals used to update position.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
BoeingGuy
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Re: Question about RNAV Approaches and who uses them.

Wed Jun 06, 2018 4:39 pm

Starlionblue wrote:
If there is an ILS we normally use that but we use RNAV approaches reasonably often. Some places don't have ILS at all (e.g. Cebu-Mactan), or only an ILS on some runways. Melbourne, for example, has ILS on 16 and 27, but for performance reasons we often require 34, so we'll do the RNAV.

One of the differences is no autoland so hand flying is mandatory below minima, but in the not too distant future it is likely non-ILS approaches will be autoland-able. ILS is an expensive piece of kit to maintain and RNAV allows the airport big savings since there's no ground equipment that needs maintenance and periodic calibration. On the other hand, a place like CDG needs ILS due to frequently poor visibility. Whether you can do away with an ILS very much depends on prevailing weather conditions.

It's really no big deal in modern airliners. Even on the 330, which is a 25 year old design, you get vertical guidance if there's a published VNAV profile.

On the 350, you get "ILS-like" guidance with the "xLS" concept. Looks and feels pretty much like an ILS except the vertical and horizontal deviation scale have double diamonds while an ILS has single diamonds. (For that matter, the 350 gives "ILS-like" guidance in both lateral and vertical on VOR and LOC approaches as well). We can also use RNP-AR approaches, which is like RNAV but with requirements for onboard monitoring and alerting. However, I've only seen those in the sim as yet.

Here's a good presentation from Airbus on the xLS concept implemented in the 350. http://www.ae-expo.eu/wp-content/uploads/2016/04/Frederic-Belloir-Airbus-xLS-concept.pdf

Airliners still tune VORs. This is done automatically by the FM, with DME and VOR signals used to update position.


Boeing airplanes have had the same feature for many years that you describe as being on the A350. It's called IAN or Integrated Approach Navigation. The FMC builds an internal ILS-like profile. It looks like an ILS approach to the crew, except the deviations on the PFD are shows as triangles rather than diamonds for ILS. Very similar to what you describe for the A350.

It flies just like ILS, except the roll mode is annunciated as FAC (final approach course) rather than LOC; the pitch mode is annunciated as G/P (Glidepath) rather than G/S.

As Starlionblue indicated, you are not legal to Autoland with IAN, nor am I aware of any future plans to do so. Depending upon model, it's not legal to have the autopilot engaged below about 100-200 feet. If you violate that, you get a NO AUTOLAND annunciation at 100 feet.

The 737NG, 737MAX, KC-46, 747-8, 787, and 777X have IAN thus far.

To my understanding, IAN (RNAV) approaches are used a lot. Boeing uses them at BFI and PAE sometimes. I believe they are used commercially too. SEA has them for each runway. Most major airports have them available in the FMC Database.
 
Redbellyguppy
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Re: Question about RNAV Approaches and who uses them.

Wed Jun 06, 2018 4:49 pm

I use rnav rnp reasonably often in certain places. San, DEN, BOI, GEG, ABQ come to mind quickly. The curved transitions are really nice.
 
Woodreau
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Re: Question about RNAV Approaches and who uses them.

Wed Jun 06, 2018 4:58 pm

Most airports that the larger airliners fly into have ILSs and RNAV approaches, so the RNAV is redundant.

I know Alaska has a lot of proprietary RNAV approaches into airports in Alaska..

About the only airport I use RNAV to is San Diego RNAV 27, Las Vegas - RNAV visual to 19R/7L, Orlando RNAV to 36L. Washington Reagan - RNAV Visual 19 - our box has an RNAV Visual to 31 in LaGuardia, but it's much more fun to fly the Expressway Visual to 31. The RNAV Visual 31 doesn't exactly follow the charted Expressway Visual.

Everything else is covered by an ILS.

While on the Airbus 320 the avionics does tune VORs and DMEs in the background - it's a backup to the GPS signals. There is no way to follow a VOR or NDB raw data with the autopilot. You can manually track the VOR course with heading mode. Or plug in an inbound course on the FMS to have the autopilot to follow what it calculates is the inbound course to a nav database waypoint that happens to coincide with a VOR or NDB station.
Bonus animus sit, ab experientia. Quod salvatum fuerit de malis usu venit judicium.
 
BravoOne
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Re: Question about RNAV Approaches and who uses them.

Wed Jun 06, 2018 5:11 pm

Twenty years from now the ILS approach will be rendered to the dust bowl and NEXTGEN or in Europe, LINK 2000 will be the mainstay of ATC, assuming we don't run out of money before then. NEXTGEN is years behind and millions in the red but it's still coming. In 1993 getting CPDLC/FANS 1A off the ground seemed impossible but it's hear today in full force. So yes, RNAV RNP or RNAV GPS approaches will be the norm soon enough. Cheaper & safer. Just sayn.
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BravoOne
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Re: Question about RNAV Approaches and who uses them.

Wed Jun 06, 2018 5:52 pm

here today, not hear today, Sorry
 
flybaurlax
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Re: Question about RNAV Approaches and who uses them.

Wed Jun 06, 2018 8:22 pm

Alaska uses RNAV all the time.

Woodreau is right, Alaska has many proprietary RNP approach and departure procedures. Most airports in Alaska don't have reliable ILS, as it can take 2 weeks to get a mechanic out to fix equipment. RNP became essential within the state of Alaska, as it allowed the plane to continue to lower minimums not available before. RNP is essentially RNAV with strict aircraft and crew requirements, and it ensures accuracy of the system is within, well, "Required Navigation Performance."

SEA and many other large airports in the US use RNAV/RNP, however the overall ATC system doesn't really support utilizing it to its maximum potential. The dive and drive step descents are still a thing.

https://newsroom.alaskaair.com/2005-12- ... al-Airport

https://blog.alaskaair.com/tag/rnp/

http://www.boeing.com/commercial/aeroma ... laska.html

https://www.ainonline.com/aviation-news ... investment

https://www.youtube.com/watch?v=EhrzGOKDNLs

There's more on Google, too.
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Starlionblue
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Re: Question about RNAV Approaches and who uses them.

Thu Jun 07, 2018 1:36 am

Thanks for the info on Alaska. The RNAV (RNP) RWY33 to Anchorage has this fun spiral. Can't do that with an ILS!

http://155.178.201.160/d-tpp/1806/01500RR33.PDF
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
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Starlionblue
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Re: Question about RNAV Approaches and who uses them.

Thu Jun 07, 2018 1:56 am

BoeingGuy wrote:
Starlionblue wrote:
If there is an ILS we normally use that but we use RNAV approaches reasonably often. Some places don't have ILS at all (e.g. Cebu-Mactan), or only an ILS on some runways. Melbourne, for example, has ILS on 16 and 27, but for performance reasons we often require 34, so we'll do the RNAV.

One of the differences is no autoland so hand flying is mandatory below minima, but in the not too distant future it is likely non-ILS approaches will be autoland-able. ILS is an expensive piece of kit to maintain and RNAV allows the airport big savings since there's no ground equipment that needs maintenance and periodic calibration. On the other hand, a place like CDG needs ILS due to frequently poor visibility. Whether you can do away with an ILS very much depends on prevailing weather conditions.

It's really no big deal in modern airliners. Even on the 330, which is a 25 year old design, you get vertical guidance if there's a published VNAV profile.

On the 350, you get "ILS-like" guidance with the "xLS" concept. Looks and feels pretty much like an ILS except the vertical and horizontal deviation scale have double diamonds while an ILS has single diamonds. (For that matter, the 350 gives "ILS-like" guidance in both lateral and vertical on VOR and LOC approaches as well). We can also use RNP-AR approaches, which is like RNAV but with requirements for onboard monitoring and alerting. However, I've only seen those in the sim as yet.

Here's a good presentation from Airbus on the xLS concept implemented in the 350. http://www.ae-expo.eu/wp-content/uploads/2016/04/Frederic-Belloir-Airbus-xLS-concept.pdf

Airliners still tune VORs. This is done automatically by the FM, with DME and VOR signals used to update position.


Boeing airplanes have had the same feature for many years that you describe as being on the A350. It's called IAN or Integrated Approach Navigation. The FMC builds an internal ILS-like profile. It looks like an ILS approach to the crew, except the deviations on the PFD are shows as triangles rather than diamonds for ILS. Very similar to what you describe for the A350.

It flies just like ILS, except the roll mode is annunciated as FAC (final approach course) rather than LOC; the pitch mode is annunciated as G/P (Glidepath) rather than G/S.

As Starlionblue indicated, you are not legal to Autoland with IAN, nor am I aware of any future plans to do so. Depending upon model, it's not legal to have the autopilot engaged below about 100-200 feet. If you violate that, you get a NO AUTOLAND annunciation at 100 feet.

The 737NG, 737MAX, KC-46, 747-8, 787, and 777X have IAN thus far.

To my understanding, IAN (RNAV) approaches are used a lot. Boeing uses them at BFI and PAE sometimes. I believe they are used commercially too. SEA has them for each runway. Most major airports have them available in the FMC Database.


Great info. Thanks!

As mentioned above you get NPA guidance on the Airbus 320 and 330. (Side note: I wonder when that was implemented.) However, the presentation differs sharply compared to the 350 and 380.

- On the 330, lateral mode APP NAV and vertical mode APP NAV, followed by the integrated mode FINAL APP. The vertical deviation indication is a "brick".
- On the 350, the FM generates an ILS-like display, with lateral mode F-LOC and vertical mode F-G/S. Deviation scales are double diamonds.

On most 330s, the autopilot automatically disconnects at 50 feet below minima. On our newer 330s, and on the 350 you get a flashing "DISCONNECT AP FOR LDG" message instead
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
BoeingGuy
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Re: Question about RNAV Approaches and who uses them.

Thu Jun 07, 2018 2:45 am

Starlionblue wrote:
BoeingGuy wrote:
Starlionblue wrote:
If there is an ILS we normally use that but we use RNAV approaches reasonably often. Some places don't have ILS at all (e.g. Cebu-Mactan), or only an ILS on some runways. Melbourne, for example, has ILS on 16 and 27, but for performance reasons we often require 34, so we'll do the RNAV.

One of the differences is no autoland so hand flying is mandatory below minima, but in the not too distant future it is likely non-ILS approaches will be autoland-able. ILS is an expensive piece of kit to maintain and RNAV allows the airport big savings since there's no ground equipment that needs maintenance and periodic calibration. On the other hand, a place like CDG needs ILS due to frequently poor visibility. Whether you can do away with an ILS very much depends on prevailing weather conditions.

It's really no big deal in modern airliners. Even on the 330, which is a 25 year old design, you get vertical guidance if there's a published VNAV profile.

On the 350, you get "ILS-like" guidance with the "xLS" concept. Looks and feels pretty much like an ILS except the vertical and horizontal deviation scale have double diamonds while an ILS has single diamonds. (For that matter, the 350 gives "ILS-like" guidance in both lateral and vertical on VOR and LOC approaches as well). We can also use RNP-AR approaches, which is like RNAV but with requirements for onboard monitoring and alerting. However, I've only seen those in the sim as yet.

Here's a good presentation from Airbus on the xLS concept implemented in the 350. http://www.ae-expo.eu/wp-content/uploads/2016/04/Frederic-Belloir-Airbus-xLS-concept.pdf

Airliners still tune VORs. This is done automatically by the FM, with DME and VOR signals used to update position.


Boeing airplanes have had the same feature for many years that you describe as being on the A350. It's called IAN or Integrated Approach Navigation. The FMC builds an internal ILS-like profile. It looks like an ILS approach to the crew, except the deviations on the PFD are shows as triangles rather than diamonds for ILS. Very similar to what you describe for the A350.

It flies just like ILS, except the roll mode is annunciated as FAC (final approach course) rather than LOC; the pitch mode is annunciated as G/P (Glidepath) rather than G/S.

As Starlionblue indicated, you are not legal to Autoland with IAN, nor am I aware of any future plans to do so. Depending upon model, it's not legal to have the autopilot engaged below about 100-200 feet. If you violate that, you get a NO AUTOLAND annunciation at 100 feet.

The 737NG, 737MAX, KC-46, 747-8, 787, and 777X have IAN thus far.

To my understanding, IAN (RNAV) approaches are used a lot. Boeing uses them at BFI and PAE sometimes. I believe they are used commercially too. SEA has them for each runway. Most major airports have them available in the FMC Database.


Great info. Thanks!

As mentioned above you get NPA guidance on the Airbus 320 and 330. (Side note: I wonder when that was implemented.) However, the presentation differs sharply compared to the 350 and 380.

- On the 330, lateral mode APP NAV and vertical mode APP NAV, followed by the integrated mode FINAL APP. The vertical deviation indication is a "brick".
- On the 350, the FM generates an ILS-like display, with lateral mode F-LOC and vertical mode F-G/S. Deviation scales are double diamonds.

On most 330s, the autopilot automatically disconnects at 50 feet below minima. On our newer 330s, and on the 350 you get a flashing "DISCONNECT AP FOR LDG" message instead


Boeing airplanes will disconnect the autopilot at touch down if you attempt to land during an IAN approach. There is no rollout guidance. All Boeing airplanes have a “safety flare” that will do a flare if you are foolish enough to attempt to auto land in an incorrect mode (e.g. not ILS or GLS).

Also, EICAS airplanes will mode fail FAC and G/P and annunciate the AUTOPILOT Caution alert at 50 feet if the autopilot is still engaged during an IAN approach. 737s give an “AUTOPILOT” aural alert.

The NPA scales are probably similar to the NPS scales (Nav Performance Scales).
 
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Starlionblue
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Re: Question about RNAV Approaches and who uses them.

Thu Jun 07, 2018 3:15 am

"Safety flare". Love it. :D
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
tealnz
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Re: Question about RNAV Approaches and who uses them.

Thu Jun 07, 2018 12:36 pm

 
N47
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Re: Question about RNAV Approaches and who uses them.

Thu Jun 07, 2018 3:24 pm

Realistically ILS will not go away within the next 40-50 years. The Ground Based Augmentation System or GBAS (GLS approaches) is a GPS based system that was supposed to render ILS useless, however that came with it own issues like multipath interference of the ground reference antennas. While the system was being tested at EWR they ran into huge problems caused by truckers using GPS spoofing devices so their employers would not be able to track them, those spoofing devices also affected the GBAS reference antennas. There was a campaign afterwards which involved using RF localizing equipment to identify these truckers pull them over and confiscate their spoofing devices. Currently GLS is authorized to provide CAT I guidance with CAT II and III being currently worked on.

In the US, an RNAV navigation solution is reliant on the Wide Area Augmentation System (WAAS) which is basically GPS positioning corrected at various locations around the US. RNAV approaches are used very often on runways that don't have ILS or have curved approaches (e.g. EWR Runway 29, and JFK Runway 13L), or when the ILS is out of maintenance. RNAV arrivals on the other hand are used on a daily basis. If the winds are right you can tune to Live ATC and listen to NY approach and hear as they assign them. There are plans to get these approaches to be CAT I capable, however, that is in the future.
 
N47
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Re: Question about RNAV Approaches and who uses them.

Thu Jun 07, 2018 3:45 pm

After some digging around it I may have misstated some information. Not all RNAV approaches are WAAS, as some can be solely GPS such as this one (http://155.178.201.160/d-tpp/1806/00285RRY29.PDF) where the minima are determined by how accurate you can determine your position measure by the RNP. There are also WAAS GPS approaches which are able to get CAT I-like guidance down to 200 ft. they are Localizer Performance with Vertical guidance or LPV approaches such as the one here (http://155.178.201.160/d-tpp/1806/00583R4L.PDF), but these require WAAS-capable GPS devices.
 
N47
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Re: Question about RNAV Approaches and who uses them.

Thu Jun 07, 2018 3:51 pm

Here are the sites that explain the difference between RNAV (RNP) and RNAV (GPS) here in the US

RNAV (RNP)
https://www.faa.gov/about/office_org/he ... /rnav_rnp/

RNAV (GPS)
https://www.faa.gov/about/office_org/he ... /rnav_gps/

And here it of the same runway (4R at EWR) for both RNAV (GPS) and RNAV (RNP)

RNAV (GPS)
http://155.178.201.160/d-tpp/1806/00285RY4R.PDF

RNAV (RNP)
http://155.178.201.160/d-tpp/1806/00285RRZ4R.PDF
 
BravoOne
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Re: Question about RNAV Approaches and who uses them.

Thu Jun 07, 2018 4:17 pm

Not sure about your 40 to 50 year numbers, but knowing the FAA I guess anything is possible. Also..are you a pilot who use the airway system on a regular basis? If so, you must be witnessing the dramatic evolution of RNAV procedures that are popping up monthly both in enroute and terminal airspace, FWIW, the FAA staff that I work says no more ILS in training, just RNAV GPS and RNP/AR approaches from now on. Of course still has to be basic ILS but you get their drift. There is pushback, especially regarding the RNP (AR), but it;s still coming to an airport near you soon.
 
N47
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Re: Question about RNAV Approaches and who uses them.

Thu Jun 07, 2018 7:46 pm

The talk of removing ILS systems went on 40 years ago and its still going on now. I am a big proponent of RNAV procedures and their benefits are immense, overall GPS is the best thing that happened to navigation since flying started, however, GPS is not available 100% of the time and is not available 100% of the time with the accuracy thats needed to land an aircraft so there needs to be a redundancy to make sure that aircraft can land safely in those types of conditions. That redundancy is and will likely be ILS. Now, there are ways to get RNAV solutions from ground based infrastructure (namely DMEs), and that is currently being worked on (NextGen DME: https://www.faa.gov/about/office_org/he ... xtgen_dme/). However DMEs are currently not accurate enough to provide guidence with LPV minima.
 
jetmatt777
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Re: Question about RNAV Approaches and who uses them.

Fri Jun 08, 2018 12:26 am

N47 wrote:
The talk of removing ILS systems went on 40 years ago and its still going on now. I am a big proponent of RNAV procedures and their benefits are immense, overall GPS is the best thing that happened to navigation since flying started, however, GPS is not available 100% of the time and is not available 100% of the time with the accuracy thats needed to land an aircraft so there needs to be a redundancy to make sure that aircraft can land safely in those types of conditions. That redundancy is and will likely be ILS. Now, there are ways to get RNAV solutions from ground based infrastructure (namely DMEs), and that is currently being worked on (NextGen DME: https://www.faa.gov/about/office_org/he ... xtgen_dme/). However DMEs are currently not accurate enough to provide guidence with LPV minima.


I remember recently there was a GPS outage over Arizona and New Mexico as the military was running an exercise for GPS jamming signals.
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Starlionblue
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Re: Question about RNAV Approaches and who uses them.

Fri Jun 08, 2018 1:41 am

ICAO is working to harmonise the standards and naming. As I understand it, the plan is for RNAV and RNP to be the main categories. Approaches named GPS only will presumably disappear.

This document from Airbus gives a good overview of developments. https://www.icao.int/MID/Documents/2015 ... ective.pdf

Approaches called RNAV (GPS) in the US will often be called RNAV (GNSS) internationally. GNSS is the umbrella term for a satellite-based navigation system, meaning any of GPS, GLONASS, Galileo and so on. Essentially the approach designer doesn't care which system your aircraft is using as long as it knows where it is. ;)
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
N47
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Re: Question about RNAV Approaches and who uses them.

Fri Jun 08, 2018 1:37 pm

jetmatt777 wrote:
N47 wrote:
The talk of removing ILS systems went on 40 years ago and its still going on now. I am a big proponent of RNAV procedures and their benefits are immense, overall GPS is the best thing that happened to navigation since flying started, however, GPS is not available 100% of the time and is not available 100% of the time with the accuracy thats needed to land an aircraft so there needs to be a redundancy to make sure that aircraft can land safely in those types of conditions. That redundancy is and will likely be ILS. Now, there are ways to get RNAV solutions from ground based infrastructure (namely DMEs), and that is currently being worked on (NextGen DME: https://www.faa.gov/about/office_org/he ... xtgen_dme/). However DMEs are currently not accurate enough to provide guidence with LPV minima.


I remember recently there was a GPS outage over Arizona and New Mexico as the military was running an exercise for GPS jamming signals.


Yes this is actually very frequent. The military does a lot of GPS jamming and spoofing around Andrews AFB. NOTAMs are published to advise pilots on the outages.

The FAA monitors GPS outages on this website: http://www.nstb.tc.faa.gov/24Hr_WaasLPV200.htm

And does a quarterly report Performance Analysis Report, here is the latest: http://www.nstb.tc.faa.gov/reports/PAN101_0518.pdf

If you go to pages 44-50 they show some plots of where GPS outages were observed for that quarter. Page 49 and 50 shows that region you are referring to.
 
Adispatcher
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Re: Question about RNAV Approaches and who uses them.

Fri Jun 08, 2018 9:48 pm

N47 wrote:

Yes this is actually very frequent. The military does a lot of GPS jamming and spoofing around Andrews AFB. NOTAMs are published to advise pilots on the outages.

The FAA monitors GPS outages on this website: http://www.nstb.tc.faa.gov/24Hr_WaasLPV200.htm

And does a quarterly report Performance Analysis Report, here is the latest: http://www.nstb.tc.faa.gov/reports/PAN101_0518.pdf

If you go to pages 44-50 they show some plots of where GPS outages were observed for that quarter. Page 49 and 50 shows that region you are referring to.


Center NOTAMs, what a blast to read.

Interesting NTSB link. It is cool to see graphically. I see blocks of time where there may be outages depending on if RNP .3, .1, etc. That led me to another NTSB link graphically showing RAIM coverage. Thanks.
 
IAHFLYR
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Re: Question about RNAV Approaches and who uses them.

Sat Jun 09, 2018 1:18 pm

Continental Airlines was flying RNAV approaches to IAH as Special Procedures back in the mid 1990's with their early B733, B735 and B752's. They sure helped the arrival rates when an ILS went down being able to use an RNAV approach for those CO aircraft. IAH ATC also had a waiver to the 7110.65 that allowed simultaneous to the 8/26 and 9/27 complex's that was later expanded to allow for the Triple Simuls once the north runway opened in 2003. Those approaches eventually made their way to become public procedures and the .65 was also changed the wording to allow dual/trip independent ops using RNAV or ILS procedures.

As was mentioned previously though, quite a few of the ATC folks did not use the RNAV's unless they were the only approach to that runway while a few others would just assign the RNAV to the CO capable aircraft. They worked flawlessly without any issues.
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BoeingGuy
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Re: Question about RNAV Approaches and who uses them.

Sat Jun 09, 2018 10:23 pm

IAHFLYR wrote:
Continental Airlines was flying RNAV approaches to IAH as Special Procedures back in the mid 1990's with their early B733, B735 and B752's. They sure helped the arrival rates when an ILS went down being able to use an RNAV approach for those CO aircraft. IAH ATC also had a waiver to the 7110.65 that allowed simultaneous to the 8/26 and 9/27 complex's that was later expanded to allow for the Triple Simuls once the north runway opened in 2003. Those approaches eventually made their way to become public procedures and the .65 was also changed the wording to allow dual/trip independent ops using RNAV or ILS procedures.

As was mentioned previously though, quite a few of the ATC folks did not use the RNAV's unless they were the only approach to that runway while a few others would just assign the RNAV to the CO capable aircraft. They worked flawlessly without any issues.


I’m assuming they flew it in LNAV and VNAV. IAN didn’t exist back then.
 
IAHFLYR
Posts: 3973
Joined: Sat Jun 25, 2005 12:56 am

Re: Question about RNAV Approaches and who uses them.

Sun Jun 10, 2018 3:55 am

BoeingGuy wrote:
I’m assuming they flew it in LNAV and VNAV. IAN didn’t exist back then.


I was a controller so not sure, but I believe it was LNAV/VNAV that the flew. The IAN sounds similar to what CO was working with GLS (GBAS) approach procedures when the merger came along. The GLS pretty much gave the crew ILS information on the PDF. I was lucky enough to fly a couple of GLS approaches in the B738 sims and it was so much like flying an ILS to my limited knowledge that I thought that was what I was flying. If I'm correct in remembering IAH and EWR had GBAS ground stations built, but I retired before I actually saw them flying the approaches on revenue flights.

https://aerospace.honeywell.com/en/~/me ... nes-cs.pdf
Any views shared are strictly my own and do not a represent those of any former employer.
 
BoeingGuy
Posts: 4982
Joined: Fri Dec 10, 2010 6:01 pm

Re: Question about RNAV Approaches and who uses them.

Sun Jun 10, 2018 8:33 pm

IAHFLYR wrote:
BoeingGuy wrote:
I’m assuming they flew it in LNAV and VNAV. IAN didn’t exist back then.


I was a controller so not sure, but I believe it was LNAV/VNAV that the flew. The IAN sounds similar to what CO was working with GLS (GBAS) approach procedures when the merger came along. The GLS pretty much gave the crew ILS information on the PDF. I was lucky enough to fly a couple of GLS approaches in the B738 sims and it was so much like flying an ILS to my limited knowledge that I thought that was what I was flying. If I'm correct in remembering IAH and EWR had GBAS ground stations built, but I retired before I actually saw them flying the approaches on revenue flights.

https://aerospace.honeywell.com/en/~/me ... nes-cs.pdf


IAN is something different. I described it earlier. GLS modes and deviations are identical to ILS.

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