The current rules allow for one turn to final under APCH...so it doesnt have to be the AR cost to the airline.
Or, pretty simple, put in the 'T', let the ac make the turn. No harm , no foul

ICAO missed kills ya though

However I don't think you can do that at 3-4 miles from the threshold at a few hundred feet which is what is required here.

But the minima would be nowhere near an -AR or ILS, would it?

You would have to look at the approach/missed to see where the obstacles are. Public RNP AR/APCH is 0.3 RNP. RNP 0.1 do pretty well, but that is more expensive for the airline.

Couple of key factors for the turn location:
1. FROP at 500 feet
2. 30 seconds of stabilized flight before minima
3. Min 250 HAT for minima.

Theoretically, you can have a 2nm short final. (Ask WJ in Canada!) That close in, with FAS, the turns can be pretty tight, 2nm radius for 737. Perhaps only a quarter delta turn could get you in there nicely. That may get you around that tower(s) on final to RW14, not sure about RW34.

With the public RNP, you could have a 15 degree angle point at 2 miles. Up to 15 degrees is not considered a turn. I see they have a 12 degree angle, so its a tight one. That may also get you past those towers. or, move the towers!

I beleive the cost for an ILS is about $2Million per runway end.

If the locals dont want an airport, why not just close it, flog the vacant real estate to the chinese, hell they would probably buy the lot when property prices collapse and unemployment goes through the roof.

Just some info, to add depth to the discussion.

1. Gold Coast are not putting in hial for 14 approaches. They don't have the real estate for it. Unfortunately, this doesn't help. As has been stated the problem at Goldy is vis more than cloud base.

2. The current Naverus rnp approaches for Qantas have a roll out point at 2 mm from threshold, with rd turn before it. The icao ones coming later in the yr will be same.

3. There have been rwy aligned rnavs already designed for 14. Final at 5nm with 10-15° turn. The designs have been floating around for 3yrs, but can't be implemented due noise issues. If ils gets approved, then new rnavs will come.

4. Thankfully the terrain environment to the south will not have a bad impact on rnp-at missed approach.

5. Generally rnp minima is about 100-150ft higher than ils, and about 100ft lower than rnav. The difference at Goldy will be Currumbin hill and how accurate survey data we can get.

6. I didn't say it wasn't going to happen. But there is a long journey still to go, as technology develops there might not be a need for one. Gbas is about to go live at yssy. Gbas would allow us to solve a lot of problems at the Gold Coast.


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Excuse my typing, I'm on an iPhone and autocorrect doesnt come with an aviation acronym dictionary


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It spelt "Android" correctly! :D :}

Do you mean RF turn? I'm havung trouble keeping up with the designer language you and underfire are using.

Yes that is what he means, an RF turn to a short final.
If I remember the design correctly, the Naverus criteria goes down to 0.10/0.15 RNP AR. The FAF is at the beginning of the turn, not the end.
Not sure how ICAO would look at that, but an exemption is always possible for the National Carriers, difficult for international carriers.

FROP-final rollout point, end of the turn, tangent to final.

RNP APCH the 'T' configs you see. (now one coded turn allowed)

ILS min 200' HAT (height above threshold)

RNP min 250' HAT

That will always be the sticking point. Air Asia doing RNP-ARs? Since the national carrier is about to become extinct :}, I think the overseas market/carriers will be the driver for what goes in...

Well, thats not exactly the point. It is somewhat convoluted.

Exemptions to the standards are easy for CASA to grant within their area of pervue. ASA and CASA have control over the National Carriers.
When International Carriers get involved, per the Chicago Convention, the airport and procedures must meet ICAO standards. Exemptions to these standards are not as easy, as the ICAO stds are, well, lets say, crazy talk anways!

AUS tried to argue the RNP missed to stay the same RNP level as the approach, ie 0.3 RNP approach = 0.3 RNP missed containment areas. (ie ICAO containment assumes the world falls apart when you go missed, and the RNP containment goes from 2x 0.3 RNP or 0.6nm, to 2RNP or 2nm wide.)
Probably still hear the screams....(poor Dirk)

Surely there is enough room there to put some sort of lighting in. You have the runway and some open space there at the end. Without that it makes the whole thing a bit pointless as the you will be in the situation where the DA is low enough but the rain puts the viz is below the minima.

I suggested earlier on in this thread as to why they can't do a RNAV STAR that leads you right into an abbreviated ILS at 5 miles?

That will get you away from the houses and the hills and will be available for all.

They need 450m at least for hial, this will help vis minima. Max benefit is obtained by putting in standard 900m. As I said, gold coast doesn't have the room. There are no plans for it's installation.

We looked at an rnav star to late ils option. It isn't ideal for 2 main reasons. a) I need to provide at least 2nm on loc before gp intercept. This pushes intercept out to 7nm. For a 5nm join, you wouldn't intercept gp until 3nm. Initial airline feedback was that it would be too close. b) There needs to be a nav mode change from rnav to loc at only 5nm out. Again this was argued to be too close. I think it would work, but it would involve an amount of training and trial.....with gbas though....it's a lot more possible


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Yes, 5nm is too close. Only a minor hiccup capturing the LLZ will prevent GS capture and the whole approach rapidly turns to worms. Besides, you can't descend below the local MSA (at least 1500ft? coming in over the water towards terrain) until you've captured the LLZ; you'd be above the GS by then.

GBAS could be more feasible. The cost to put in GBAS is about equal to an ILS for each runway end, so cost would be a wash.

I would like to see the GBAS approach procedures (and departures) re-thought in the criteria.

First off, there is no reason it should not be CAT III at this point in the game.

CAT I, and 250 HAT, following ILS criteria is not where GBAS should be at this point in time.

RNP transition from the STAR to GBAS 0.1 CAT III final is where this should be at. ASA as 50% owner of SmartPath should have the system at every airport in AUS, and should be dictating the criteria to ICAO.

That's strange... I've been told GBAS is orders of magnitude cheaper than ILS.

GBAS system costs about the same as 2 ILS runway ends.

You get 26 ends with the GBAS system.

With each ILS, its about $50K/year for maintenence. GBAS is little to nothing per year.

There must be room for HIALS on 32. The displaced threshold is about 600m!

Do you need an ILS on 32?

Well it sounds like there aren't many options available. :(

Airservicess' website says that the GBAS is the ILS replacement, yet it doesn't seem to be catching on anywhere. People are building replacement ILS's not GBAS systems.

After reading this it sounds like yet another aviation infrastructure project that will meander on forever with no decisions being made because it's all to hard.

Guess the RNP is the best of a bad choice.