Nav aids in Aus to be shut down?

[18-Wheeler]

From another forum, a mate of mine in the Aus Navy wrote -

In case people are interested, all ground-based navigations aids in Australia are going to be switched off in the near future. Aircraft will have to rely on performance based navigation like GPS.

I haven't worked since 2009 but this is pretty big news, I've never heard anything about it.
How true is it?

[Capn Bloggs]

a mate of mine in the Aus Navy wrote
He should stick to sailing boats. :ok:

Or, ask him what the definition of "near future" is. Perhaps it is the same timeframe for getting all 6 Collins class tubs up to speed and fully operational!

[60 & below]

I believe mainly enroute navaids will go with a reduction of aids at airdromes. E.G IRS/GPS Enroute + Approach with ILS or VOR depending on the usage at that Airdrome as a backup. With all NDB's phased out.
This will probably mean the end of circling approaches.

Have Fun
I Do
:)

[CaptainMidnight]

all ground-based navigations aids in Australia are going to be switched off in the near future.Incorrect.

Most navaids are part of an essential network for air traffic management by ATC, and those have been (or will be) upgraded or replaced when they reach end of life. Others not essential to the network have either been offered to local aerodrome owners or operators to take over, or been decommissioned if the aerodrome owner or operators have said they do not require them, or are currently being maintained until someone makes a decision.

Your mate should join an aviation industry association such as RAAA AOPA or participate in local RAPAC.

[alphacentauri]

As someone who works for the organisation in question....I can tell you that they plan to decomission 170 navaids Australia wide within the next 3 yrs, and this does include navaids at major/international aerodromes. For example I am pretty sure that the VOR's at SY and ML are on the list.

Those NAVAIDS that are to be kept in the backup infrastructure are currently being replaced. If a navaid near you is not scheduled to be replaced then there is a good chance it is being decomissioned.

So to answer all the "negative" comments

Incorrect.

Most navaids are part of an essential network for air traffic management by ATC, and those have been (or will be) upgraded or replaced when they reach end of life. Others not essential to the network have either been offered to local aerodrome owners or operators to take over, or been decommissioned if the aerodrome owner or operators have said they do not require them, or are currently being maintained until someone makes a decision.Quite incorrect, navaids are no longer an essential network for traffic management. It is cheaper and easier to replace a navaid with a waypoint. The only organisation/s in the country that is permitted to operate navaids is AsA and RAAF. So they are not being offered to aerodromes or private consortiums because they don't have the approvals to operate them.

Not all NDB's phased out, some of them are part of the backup navaid network and are currently being replaced/upgraded. If you do find the list, you will quite surprised as to which navaids are on it

I would say that in 3-5 years ground based navaids will be far and few between. Well thats the info they have provided to us for approach planning requirements.

Alpha

[alphacentauri]

Also forgot to add....

The reason the Navy know about this is because they can/do use some of the coastal NDB's for navigation. All of the coastal NDB's are published on the nautical charts and they use them as a cross check for navigation....well they did when I worked for them.

[18-Wheeler]

Thanks AlphaC.
I can see how for modern airliners it's not a problem but for blokes out in the bush it'd be a heck of a change.

[Jabawocky]

NDB's mainly are the species being culled.

[Ex FSO GRIFFO]

This 'process' has been going on for over 20 years or so now.

For example, how long is it since the 'non-essential' Perth NDB at Pt Waylen, Attadale / Alfred Cove, was decommissioned due to it being deemed 'uneconomic' / 'non-essential'..?

This NDB had a 'terrific' range out over the Indian Ocean, with some of the 'Springbok' and Qantas crews reporting it at a 'looong waaay' out, at times...
No GPS then......

Anybody remember it? Used to use it??

There must be many more such examples.

Similarly, there used to be a Marine NDB at Cape Leeuwin, which some pilots who knew about it, used to......

Dems were de days.....:}

The loss of 'domestic' NDB's will be sad loss for the G/A guys, especially at 'remote locations' in de middle of de night....:eek:

[dl_88]

would this mean a huge change in all the navigation syllabuses? Since the PPL & CPL navigations have a huge focus on the nav-aids.

[Tinstaafl]

Yeah. CASA will probably update the exams to include LORAN. :E

[QFF]

Where does that leave TSO-C129 (non-WAAS) GPS's which require an alternate with a ground based aid ?

A ploy to have everyone change over to WAAS GPS's which are unable to receive the WAAS signals here is Oz, just to not need an alternate without a ground based aid?

[CaptainMidnight]

Perhaps you should talk to your ATS systems people alphacentauri because the information to Industry comes from them. They also indicated that some navaids are required for air traffic management outside surveillance coverage, due not all aircraft being equipped with GPS-based navigation systems.

ASA and Defence are not the only two "permited" to operate NAVAIDS. Quite a number of NDBs are privately operated - Renmark and Shepparton are just two that come to mind - and they have been offered to aerodrome operators for some time.

The last we heard about the SY VOR was it was to be shut down for a period while new hangars are being built, and after to be reinstated.

[LeadSled]

Quite a number of NDBs are privately operated
Folks,
Not limited to NDB, there is at least one, probably one more ILS "privately" owned and operated, there is no law that prevents an "interested party" owning and operating navaids, provided compliance witha bleeding thick book of standards is shown.
In a similar vein, there are quite a few "privately owned" approach and departure procedures that are not published and available for other users.
Tootle pip!!

[chimbu warrior]

Interestingly this may have ramifications for some of the smaller operators of medium jets (early A320's and 737 Classics), as most of those are not GPS-equipped, and (I'm told) are not a simple process to retrofit. Admittedly this is only a small number of aircraft, but would limit a few operators.

The Norfolk NDB is one of the strongest I know, and at night can be received with a strong ident and bearing from west of Coffs Harbour.

[Robbovic]

Anyone wishing to find the list of backup network naiads, look on the CASA website and find reference to a NPRM1105AS for aircraft equipage. Annex G gives a list of the navaids which will be kept after the mandate date of Feb 2016.
This list was put together by ASTRA. Look this up too; it is a consultative body made up of various members of the aviation fraternity, including QANTAS, Virgin, AOPA, RAAA etc. This body reports to the APG which is basically a coffee club of the CEO's of AsA, CASA, DoIT and Defence. APG recommends to the Ministers of Defence and Transport.
The list was formulated in 2005 and has been accepted by all these bodies. The reasoning behind the list: it is a backup in case of GPS failure and is supposed to provide guidance to the nearest suitable aerodrome - note most suitable and not preferred aerodrome. Currently there are approximately 410 non precision aids (NDB, VOR, DME). There are about 220 on the backup list. The declared position of both CASA and Airservices is that there will be a reduction to the backup network after the mandate kicks in in Feb 2016. This is easily determined by looking at published 5 and 10 year plans on the various websites.
AsA has been decommissioning aids since the 1990's on a site by site determined basis. There are a large number of aids which were commissioned in the 60's and 70's which have either outlived their original purpose or have become difficult to maintain - spares, structures, electronics, suppliers, any number of reasons. This will continue to occur. There are sites under scrutiny now as anyone who has attended a recent RAPAC can attest.
The bare facts are that it costs around 600K to replace an NDB and around 1.2mill to replace a VOR. A DME not so much because the antenna and electronic setups are simpler. The big players in aviation are not prepared to pay for this replacement in the long run when they are equipping to run GNSS nav system. ASTRA was told in 2005 that to replace the ground based nav system outside of the backup network would cost between 140 and 200 million dollars. You can do the sums for the current cost.

[Robbovic]

Leadsled

Not quite. Airservices is the only holder of a civil CASR Part 171 certificate in Australia. All privately owned aids are maintained under contract by Airservices staff. Privately owned aids are installed and commissioned under that 171 certificate.

[alphacentauri]

CaptainMidnight

ASA and Defence are not the only two "permited" to operate NAVAIDS. Quite a number of NDBs are privately operated - Renmark and Shepparton are just two that come to mind - and they have been offered to aerodrome operators for some time.

As the only holder of the CASR 171 certificate, AsA is the only civilian organisation permitted to operate navaids. They can be owned by anybody, but they can only be operated under the 171 certificate. The aerodromes can buy them, but the only way they can be operated is under contract with AsA....which is going to cost the aerodromes more money.

As far as I know the SY VOR is scheduled to be decommissioned. I have not heard of any plans to re-instate it...but that doesn't mean it won't happen.

Alpha

[4Greens]

GPS is run and controlled by the US military. It can be downgraded or even switched off. It can remain on but coded for military use only.

Removing ground based aids before there is a back up system is a recipe for trouble.

[Kooim00]

So for those of us that work in non-radar towers doing procedural approach, does that mean we'll finally get decent lat sep drawings based on real GPS tolerences and actually be able to use GPS/RNAV equipped aircraft properly?

[Oriana]

Yeah. CASA will probably update the exams to include LORAN
:D:D:D:D:):):D:D:D

[fixa24]

Disregard.....

[fixa24]

So for those of us that work in non-radar towers doing procedural approach, does that mean we'll finally get decent lat sep drawings based on real GPS tolerences and actually be able to use GPS/RNAV equipped aircraft properly?
They are on their way. I've seen the drafts. Useable, but VOR tolerances are much better..

[training wheels]

would this mean a huge change in all the navigation syllabuses?

They're still using the 727 for ATPL flight planning and performance and loading exams! LOL!

BTW, I thought some modern airliners use enroute Nav Aids to update their FMS position? Or can they do without these enroute updates?

[morno]

TrainingWheels,
The way I understand it (disclaimer, I operate an aircraft with an FMS, however other FMS's could be different), is that the FMS updates its position mainly using the inbuilt GPS, and then uses VOR and DME in the event that the GPS stops working. However, there is also a way to tell the FMS which one you want it to update exclusively by (ie. if for some reason you want it to stop using the GPS, then just select VOR and DME).

I think I just confused myself writing that, so might be back to the book to update myself on exactly how it works, but that's basically the gist of it.

morno

[training wheels]

Ok, thanks morno ... I remember reading about this for ATPL systems but that was years ago.

[ReverseFlight]

Hi, training wheels. This is an excerpt from a typical FMS setup for a modern airliner:
WITHOUT GPS PRIMARY
The FMS position is computed from the three IRS positions, that are combined to provide a MIXIRS position. The radio position is also combined, if two DMEs, a VOR/DME or a GPS supplemental are available. The GPS supplemental is considered to be an additional form of NAVAID, and can be accepted, if it falls within the radio position or the MIXIRS position.
WITH GPS PRIMARY
The GPS interfaces directly with the IRS that outputs a GPIRS position. When a GPIRS position is available, it overrides the RADIO position, if available. Therefore,the FMS position tends toward the GPIRS position.GPS is Primary if GPS is used as the primary source of navigation by the FMS. This happens on long oceanic flights where ground navaids are not available. If GPS is unavailable for whatever reason, the FMS will display a GPS downgrade message and you will have to rely on available navaid signals to quantify the position error of the FMS. In this case you should not rely on the FMS data for an approach and you would probably seek vectors and fly raw data based on ground navaids for greater navigation accuracy.

[training wheels]

Thanks RF for the info .. it's a alot more sophisticated than than the UNS 1K FMS we use in our aircraft ..

[Nautilus Blue]

Quite incorrect, navaids are no longer an essential network for traffic management.

They are not essential, but some of the are very very useful. Under the separation standards we use NDB's are more accurate than GPS under some circumstances. Also passing over a VOR/DME allows us the "reset" the nav tolerances of aircraft with IRS.

Interestingly this may have ramifications for some of the smaller operators of medium jets (early A320's and 737 Classics), as most of those are not GPS-equipped,

Wouldn't they have IRS? Admittedly that only covers en-route, but people flew non navaid routes long before GPS.

ReverseFlight thats interesting. The way I read that, GPS Primary averages three IRS and the GPS position and ignores navaids. Without GPS Primary, it averages three IRS positions and a radio fix, and adds GPS only if the GPS position agrees. The difference seems to be the trust in the GPS position. Is GPS Primary selected by the crew or the FMS?

[Clearedtoreenter]

Have ASA spoken to CASA about getting rid of VORs and NDBs?

To quote CAAP 179a

'4. If a TSO-C129 or C129a receiver is used at any time, or a C145a or C146 receiver is used during a period when FDE is not predicted to be available, an alternate visual approach or instrument approach based on NDB or VOR must be planned.'

Looks like the end of 129's for IFR use and very bad luck if you arrive with a 146 needing an approach when there is a RAiM outage.

There seems to be a lot more 146 fault detection outages than for 129's. Then a 146 becomes a 129 anyway.

Also,

'Automation Induced Complacency
The highly automated nature of navigational calculations using GNSS provides significant benefits including increased reliability, accuracy, proficiency and system monitoring ability. However, it can be difficult to stay alert and detect gross errors when monitoring automatic equipment. The operators’ continuing experience of highly accurate positioning information from GNSS can lead to the assumption of infallibility promoting a complacent attitude resulting in decreased crosschecking of the system.'

Well, that's alright now then... Let's just get rid of VORs and NDBs because we dont now need anything to crosscheck against anyway.... :ugh:

[Robbovic]

I refer you again to NPRM 1105AS, a CASA document.
This is the driver behind any decommissioning.

[Up-into-the-air]

From the NPRM:

Civil Aviation Safety Authority - NPRM 1105AS (http://www.casa.gov.au/scripts/nc.dll?WCMS:STANDARD::pc=PC_100829)


Existing Private and AWK aircraft (those placed on the Australian Civil Aircraft Register before 06 February 2014
1 x TSO-C145 or -C146 or -C196 (or later versions) GNSS
OR
1 x TSO- C129 GNSS + ADF or VOR (See Note 1)
Note: TSO-C129 Navigator is unlikely to support ADS-B requirement/functionality.

By: 04 February 2016and:

New Private and AWK aircraft (those first placed on the Australian Civil Aircraft Register after 06 February 2014)
1 x TSO-C145 or -C146 or -C196 (or later versions) GNSS

BY: 06 February 2014
and the big metal:

Existing aircraft used in public transport services (those placed on the Australian Civil Aircraft Register before 06 February 2014)
2 x TSO-C145 or -C146 or -C196 (or later versions) GNSS
OR
RNP capable aircraft as approved by CASA
OR
1 x TSO-C129, TSO-C145 or -C146 or –C196 GNSS + ADF or VOR (See Note 1)

BY: 04 February 2016and:

New aircraft used in public transport services (those first placed on the Australian Civil Aircraft Register on or after 06 February 2014), or new GNSS installations in aircraft placed on the Register before 06 February 2014
2 x TSO-C145 or -C146 or -C196 (or later versions) GNSS
OR
RNP capable aircraft as approved by CASA
OR
1 x TSO-C145 or -C146 or -C196 GNSS + ADF or VOR (See Notes 1 and 2)
BY: 06 February 2014How's that for creating more confusion between OZ and ICAO requirements - Bring on the next audit!!

[ReverseFlight]

Is GPS Primary selected by the crew or the FMS? Not by the crew. If the aircraft has GPS primary, the FMS will confirm it has GPS primary if specific RNP tolerances are maintained. If all GPS receivers fail, the RNP tolerances can still be satisfied by IRS ONLY navigation for a specified number of hours.

[QFF]

On a related note, if NDBs were to be decommissioned, would GPS be allowed to be used in-lieu of NDBs?

I am in a situation where I am unable to do the SID out of YPJT due to not having an ADF, and have been told that GPS was in the pipeline to be approved in lieu of, then subsequently told that was not going to happen.

Given what I have heard/read, GPS is probably more accurate than NDB anyway?

I'd looked into getting an ADF a few years ago and was advised not to bother as NDBs were going the way of the dodo, that was back then...

Same with getting an HF - same mob suggested an installed satphone was the way of the future...

[alphacentauri]

QFF, in short....no. GPS won't be allowed in lieu of NDB as a blanket change. The protection areas are too different. In order for that to happen the ndb procedure will have to be re assessed using GPS protection areas.

It's more than GPS being more accurate. It may be more accurate, but how do you know when you are getting that accuracy? It's for this reason the protection areas are a little larger than those for ndb.

Alpha

[Capn Bloggs]

or a C145a or C146 receiver is used during a period when FDE is not predicted to be available....

....very bad luck if you arrive with a 146 needing an approach when there is a RAiM outage.
Check your RAIM prediction before flight. I suspect (only theorising here) that CASA is happy provided RAIM is predicted to be available. Perhaps, after that, if one sat then falls over, RAIM will still be available?

It may be more accurate, but how do you know when you are getting that accuracy?
Because it's a TSOed system. Apart from the alternate requirement, the same GPS that could easily navigate QFF on the Mantl 1 would be used to take him to within 400ft of the ground, sight unseen, out in the boondocks (assuming it's a GPS NPA kit).

[alphacentauri]

The system being TSO'd only means it will perform within certain accuracy limits as specified in the TSO. There is know way to know how the system is performing within those limits, like RNP can. So basic GPS protection areas have to cater for the worst performing TSO'd system.

A system being TSO'd has nothing to do with accuracy alone, more to do with accuracy vs performance

Yes I agree that QFF could navigate the Mantl 1 with the same perceived accuracy. And 90% of the time that might be the case. But protection areas are based on 3SD containment (99.7%) and on paper the figures reveal a wider protection area is required.

[Tinstaafl]

Admittedly, USA uses TERPS, not PANS-OPS, but they didn't seem to have a problem with GPS overlay approaches. GPS guidance was essentially used to track an NDB or VOR approach.

[alphacentauri]

Different concept. I don't believe you can fly a GPS overlay approach without monitoring the navaid for the approach. Eg you can fly an ndb approach using GPS overlay, provided the navaid is tuned, identified and monitored for the approach. At least that's how I'm led to believe it is done. What QFF wants is to be able to fly the ndb procedure using only GPS in lieu of the ndb when the ndb gets switched off.

Without work done to re assess the approach, this won't happen.

[QFF]

Alphacentauri - thanks for your replies - that makes sense.

So I guess in the wider scheme of things, shutting down navaids would save money in the longer term but those savings might be diminished by having to have procedures re-surveyed/re-designed to different standards...

It may be cheaper to keep the damn things going...

[Up-into-the-air]

Yes QFF

It may be cheaper to keep the damn things going... and:

ASA/ AirServices made a 100 MILLION dollar profit last year

There is plenty of money to keep these and keep us all safe.

[FlightPathOBN]

I know some of the ones being retired in AUS were on military bases that are being closed down. This is causing some grief with local airports that used them for nav as well.

It is not all that simple, the navaids are getting very expensive to maintain, and development around the airports causes too much interference. Many just have to be retired because they just cant tune out the interference anymore...
Air traffic is increasing, and with a tight queue, the surface navaids get disrupted as well.

GPS overlays are just that, and overlay of the existing ILS or ndb procedure, that provides waypoints for navigation. They do not require a navaid.

http://operationsbasednavigation.com/wordpress/wp-content/uploads/2012/06/SC-08-e1339435128149.jpg


Overlays are a great way to get a procedure approved through environment, as technically, the procedure and corridor are already approved. I know that 'T' configurations were designed for all runway ends at YMML, but in operation, the tracks were too varied, and there were a lot of noise complaints, so on 16 and 27, they went back to straight in RNAV GPS from the NDB location. (the private RNP procedures have waypoints on the ndb location)
The RNP AR tracks for 16 and 27 are still on operation by Qantas.

The cost to maintain and calibrate a VOR or NDB is about $50K/year for each runway end.
A GBAS system is around $2 million to install for an entire airport with up to 26 runway ends....

[Clearedtoreenter]

The cost to maintain and calibrate a VOR or NDB is about $50K/year for each runway end.

Hummm... VORs look like they might be a tad complicated to maintain but NDBs? Mostly just a shed and a washing line! Is that not why the useful VORs went at MQD and MSO but the crappy NDBs were retained?

[FlightPathOBN]

Everything in Aviation is expensive!

The NDB system is no different, the electronics, keeping signal in spec, and mostly the location, and annual maintenance.

While the airport would love to own the property, that is frequently not the case.
Set up a building, especially one of the glass ones, and it all goes to hell on you real quick.

Not sure about MQD or MSO ....

[kalavo]

And those costs won't disappear with GBAS. Not a single GLS system in the world providing ILS-like minima, and plenty of obstacles to overcome before it gets there. Won't be suprised if it goes the way of MLS. But we can be the expensive guinea pigs and provide a different solution to the rest of the world so Airservices can charge for the ground equipment.

We could have had WAAS providing coverage for the entire country at a fraction of the cost to provide the same with GBAS but Airservices kept pointing to the first version of WAAS in the states "look how much it went overbudget" well duh, they spent a lot of money figuring out how to make it work. But guess what? Now they've figured it out, it works and easy to reproduce! In 2008 there were over 1333 WAAS approaches in the US, with a plan to add another 500 a year. Try doing that with GBAS on the same budget. The more recent systems have been much closer to on time and on budget with the exception of one failed satellite launch.

But no, we'll install GBAS at the capital cities so we can cover "97% of RPT passengers", which could have (and probably will be) covered at zero cost and zero return to Airservices with Baro-VNAV instead, while the 3% that would have been covered with WAAS and won't ever get Baro-VNAV capability miss out completely (not many Baro-VNAV capable 404s around the place!)

A real shame, if we'd tacked WAAS on to the NBN satellites, it would have cost less than one GBAS install.

[FlightPathOBN]

Kalavo,

I have RNP transitions to CAT 3 Autoland with GBAS....

You tout the WAAS procedures numbers, like you are with the FAA, but in reality, there are NO or very, very few, WAAS procedure plates. The only ones I know of are helo ops in the Gulf.
I would love to hear from anyone who has a commercial AC is certified to use WAAS, has used WAAS IFR, or even, where in the hell they used it in the US!

Obviously, you have NO idea what it takes to certify an AC for WAAS. It is a different antennae system, different MMR, and different requirement for crew training.

I will certainly agree with you WAAS, SBAS, LAAS, etc, are a waste of money...

Do you understand that WAAS is an augmentation system, that it just broadcasts a correction factor through a sat? GBAS does exactly the same thing, just through a ground based receiver, at the airport you are flying to?
Why spent the $2 billion floating a sat for WAAS, when you can spend $2 million for a GBAS, and have better accuracy?

I also suppose you also werent aware that ASA is a 50% owner of the GBAS system....

[OZBUSDRIVER]

FlightPathOBN...tell the whole story!

GBAS is a separate PROPRIATORY VHF transmission system. WAAS or the augmentation thereof is solely within the SBAS system at NO EXTRA CHARGE.

GBAS does give CAT III approach capability EDIT with the addition of ground transmission infrastructures etc...but...at a penny or three.

A very big part of the reason Australia does not buy in to provide the ground based monitoring system to provide the augmentation signal for the WAAS aleady available from the Japanese MTSAT....user pays!

[OZBUSDRIVER]

AC 20-138C (http://www.faa.gov/documentLibrary/media/Advisory_Circular/AC%2020-138C.pdf)

Lot of reading..but...basic TSO146c class Delta euipment with Barro and you are well on your way in the US to LPV approaches

A telling quote
Although GPS/SBAS does not have an equipment limitation for other navigation systems onboard the aircraft, the receiver manufacturer’s operating instructions should encourage operators to retain back-up navigation systems to guard against outages or interference events.

5Hz update rate...

To date there are 100 LPV and 55 LP published approaches in the US. Considering the FAA's business model calls for 8300 LP/LPV approaches, lots of work ahead!

[FlightPathOBN]

OZ,

The GBAS signal is proprietary? That is not correct, both GBAS, WAAS and other systems are based on the standard ARINC 424.

WAAS will still have the same limitations as GPS or GBAS because it is still based from a sat. Its just a correction factor of the GPS sat signals, its just, sat based, where GBAS is ground based.

WAAS certified aircraft system is completely different than the GPS system.
It is different receivers, different antennae, and, same as GPS, must have at least 2 systems for certification.

WAAS needs quite the infrastructure to operate. Currently in the US, there are about 25 ground reference stations positioned across the United States that monitor GPS satellite data. Two master stations, located on either coast, collect data from the reference stations and create a GPS correction message. This correction accounts for GPS satellite orbit and clock drift plus signal delays caused by the atmosphere and ionosphere. The corrected differential message is then broadcast through one of two geostationary satellites, or satellites with a fixed position over the equator. So its not free by any means. AUS would have to set up similar system around the Country if they wanted the same accuracy results.

Virtually no commercial aircraft have been WAAS certified. While there are WAAS certified stand alone units, a WAAS coupled unit requires the certification of the aircraft, including flight test. Manufacturers or the airlines, do not want to switch to the system.
Currently, there are 2 WAAS sats for the US, so even one partially degraded, puts the whole system down. Like GBAS, the WAAS aircraft must have the WAAS artificial horizon for guidance.
You must still check RAIM, and monitor RAIM inflight.

So all that, and there are how many procedures available to use?

The GBAS signal broadcasts the approach procedure, That is why it is far better, as WAAS just giving a corrected GPS algorithm. The GBAS is broadcasting the same correction factor, its just ground based, AT the airport you are going to.
Here is an example of the GBAS signal, which the aircraft will use, just like the ILS beam, for approach. But, unlike the ILS beam, the GBAS is a signal which isnt interrupted by infrastructure or other aircraft.
As you can see, there is some great features, such as broadcast of multiple GPA, from which the pilot can select, and currently curved approach procedures are being tested:

"RX_WEEK";"RX_TOM";"GBAS_ID";"FAS_VAL";"FAS_LAL";"OPTYP";"SBAS_ID";"AIRPORT_ID";"RW_NO";"RW
_LTR";"APP_DESIG";"ROUTE_IND";"RPDS";"RPID";"LTP_LAT";"LTP_LON";"LTP_H";"DFPAP_LAT";"DFPAP
_LON";"TCH";"GPA";"C_WIDTH";"RW_LEN_OFFSET";"CRC_OK"
1634;303799.437500;"TATM";10.000000;40.000000;0;0;"EDVE";26;0;1;"Z";21;"G26A";52.31964167;
10.56400556;131.300000;-0.00098056;-0.01751667;15.240000;3.000000;80.000000;0;1

1634;303800.437500;"TATM";10.000000;40.000000;0;0;"EDVE";26;0;1;"Y";22;"G26B";52.31964167;
10.56400556;131.300000;-0.00098056;-0.01751667;15.240000;3.200000;80.000000;0;1

As far as AUS buying in, ASA is a 50% business owner of SmartPath. SmartPath is already CAT I certified, and CAT III autoland is being certified, but already in use in some countries by their military aircraft.

[OZBUSDRIVER]

Looks like you need some learning! Why do you think the 50% business owner cannot get a purchase within their own country?

[OZBUSDRIVER]

Actually, to be more precise. Do you think AirServices will pay for all the infrastructure at all our major aerodromes so the airlines can get CAT III for free? Do not forget, GBAS still requires a network of reference stations to calculate the correction to be transmitted to SUBSCRIBER aircraft. The device may be ARINC and TSO but it still requires access...controlled by discrete codes or whatever. It will not be free!

[OZBUSDRIVER]

I'm still too harsh. A GBAS system installed will be way too expensive to be of benefit to any aviation outside heavy iron or mil ops.

If it was my say so on provision of GPS infrastructure, I would take the same view as the US. GPS is an enabler of commerce, that is to say it returns far more to the economy than what it costs to run. Considering the expensive bit is already up there with the capability already operational, all that is required are the monitoring stations linked up to the reference uplink already in Canberra and we have WAAS over the entire continent via the MTSAT. Considering there is already 28 surveyed in ADS-B sites evenly distributed across the country...already talking to mummy...makes you just wonder about the possibilities for the nation in general. Considering the landing accidents over the years from non precision approaches in marginal wx, what cost is a life?

This argument has already been had. The Feds take a narrow view of cost recovery. We are never likely to see any government of any colour do such a thing ever again in this country.

[FlightPathOBN]

OZ,

That is not correct, the GBAS system has the 3 to 4 ref antennae at the airport. , which gather the sat GPS signal, and correct algorithm for the actual location. That correction, along with the final approach path, is sent to the aircraft. GBAS can also be used for dpartures, and a runway can be used for arrival and departures from the same end. Cant do that with ILS or VOR.

All WAAS does is correct the GPS signal. While the claim is lower minima, to 200', I doubt if you will ever see anything less than 250' in use, as that glass basement is the FAA mantra. You may see it on the charts, but permission to use...well.

As far as costs, if you have more than 2 runway ends, the GBAS cost is even with the VOR. More than that, and the $2 million to put in the GBAS is amortized very quickly.
For the airlines, the equipment on the both Boeing and Airbus new aircraft are GBAS capable, and doesnt cost anymore for you to tell them to flip that switch.
I have not seen a WAAS certified commercial system avilable or installed on a commercial aircraft.

As far as I know, there are aircraft using the GBAS at Sydney, with no extra cost.

I just dont see very much in the way of advantages of WAAS, its just a more accurate GPS system, with all of the same issues as GPS.

[Capn Bloggs]

I'm siding with OZBusdriver: WAAS would be better because it would support low minimums over the whole country. Wouldn't that be of benefit to non-RNP capable aircraft (given the heavy iron can already go to ~250ft without GBAS using RNP-AR)?

[FlightPathOBN]

Well, I look at it this way, all new Boeing and Airbus aircraft are GBAS enabled, with the Dreamliner touting full GBAS certification.

The FAA is basically providing WAAS, so they can get rid of the VOR and NDB's.

Currently, the WAAS program is kinda screwed here in the US. We have the 2 WAAS sats, CRW and CRE, basically west and east. CRW is failing. The single sat over Japan POR, will be repositioned and will be able to cover about 1/3 of the west coast of the US. How this will effect the signal on the East Coast of the US is still being worked on.

Current coverage: Note lack of WAAS coverage in AUS
http://operationsbasednavigation.com/wordpress/wp-content/uploads/2012/06/SC-16-e1339600913236.jpg
Here is what the colors on the map relate to:
http://operationsbasednavigation.com/wordpress/wp-content/uploads/2012/06/SC-20-e1339601246715.jpg


The POR sat is a single, and provides somewhat of a signal over the northern half of AUS. Due to signal strength, and lack of a second sat, I doubt if you will really ever see WAAS in AUS (unless you want to spent a few Billion to float another sat!)
Here is what the WAAS coverage the US will have with the failure of CRW and adding POR and AMR (new, not yet launched) update AMR launch has happened and POR has moved, restoring coverage to AK)

http://operationsbasednavigation.com/wordpress/wp-content/uploads/2012/06/SC-191-e1339601380676.jpg

[FlightPathOBN]

WAAS certified AC. Looks like a very specific target audience. Given there are 60 approach procedures at airports in Alaska with WAAS LPV, that figures the 737-200 with gravel kits...

http://operationsbasednavigation.com/wordpress/wp-content/uploads/2012/06/SC-17-e1339602328417.jpg

http://www.faa.gov/about/office_org/headquarters_offices/ato/service_units/techops/navservices/gnss/approaches/media/lpvlocationsAlaska02_09_12.jpg

[OZBUSDRIVER]

FlightPathOBN, POR was moved to the West Coast around 2007. If you look at your map there is a little green dot that covers Japan and as we know, WAAS is transmitted from a Geosynchronous orbiting satellite. The Japanese Ministery of Transport MTSAT! Australia only has to put in the monitoring infrastructure.

I am looking at the benefit of the entire continent. WAAS is more suited than GBAS, you have to admit that. If you are purely talking Autoland capability then by all means GBAS is a far better proposal than a purely ground based CAT III system....as long as someone is willing to pay for it.

As for your list? Not many B58s or PA31s running Proline is there?

[FlightPathOBN]

Well, they just got the WAAS coverage to Alaska in Dec 2011, so I dont know when it moved. This was dated Sep2010, and the move was just proposed. Unless you have 2 sats, you are not going to get LPV anyways...
I suppose all of the ground monitoring stations, coupled with 2 data centers would be free?
Note that in the US, it costs over $50 million dollars a year to operate, plus $50,000 PER procedure....Startup costs? well, you can just imagine...Wide Area Augmentation System - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Wide_Area_Augmentation_System)
WAAS Localizer Performance with Vertical guidance (LPV) approaches with 200-foot minimums will not be published for airports without medium intensity lighting, precision runway markings and a parallel taxiway. Smaller airports, which currently may not have these features, would have to upgrade their facilities or require pilots to use higher minimums.

Well, I am not going to agree that WAAS is better, perhaps for GA aircraft, but for commercial, it is a step backwards. What a commercial aircraft would have to do to be certified to fly WAAS, just isnt worth the time or effort. As you can see from the FAA's list, very few aircraft are certified to fly the WAAS, even after all of these years.

In reality, WAAS is only meant to replace CAT I ILS in areas where the government didnt want to keep paying for the navaid, so that is all one can hope from it.

[Flying Binghi]

.


...and still yer gotta wonder about those who base a bussiness around something they dont own or control or have any garantee of continued 'free' use..:hmm: ...at least withNDB/VOR we own and control the system.


There will be other 'backup' GPS out there some say... I see the US airforce covered shooting down Galileo satellites if the europeans wont turn them off when required..:ooh:


What we got now... about 40 odd terrorist groups tinkering with UAV/UAS... once they work out how to use a cheap GPS based targeting system we will lose civvy GPS.....








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[notaplanegeek]

Don't think so... do you know how easy it is to jam GPS signals? Have a look at what North Korea has been up to.

[FatMouse]

https://www.newscientist.com/article/dn20202-gps-chaos-how-a-30-box-can-jam-your-life/