Menu Sign In Contact FAQ
Banner
Welcome to our forums

LeSving wrote:

The first certified GPS precision approach (operational) was done in Norway in 2007. It is called SCAT-1 (GLS) and is now in operation on most/all? of Avinor’s smaller airports. I think GBAS has superseded SCAT-1.

Yes, very good….but I didn’t say precision approach….Australia had GPS RNAV approaches many, many years before anyone in Europe. The shame is that they don’t have precision GPS approaches (LPV) other than GBAS because they do not have SBAS…

YPJT, United Arab Emirates

Isn’t this (New Zealand) a GPS based RNP approach?

(doesn’t play for me in Firefox anymore; works in Chrome)

Administrator
Shoreham EGKA, United Kingdom

RF legs may require an SBAS capable navigator bit that doesn’t mean it needs to receive a SBAS signal…lateral Nav only….if you look at the plates in the Queenstown example you will see there is no DA…only an MDA((H) and the accompanying MAPt….

Correction: I believe that approach used LNAV/VNAV with Baro-correction…. Still no SBAS…

Last Edited by AnthonyQ at 14 Feb 08:16
YPJT, United Arab Emirates

This article has popped up. They are playing with GBAS in Germany.

Interesting that the 0.5 to 1.5db improvement makes any difference. Most people won’t detect that.

That’s not a lot!

Administrator
Shoreham EGKA, United Kingdom

Peter wrote:

That’s not a lot!

It would be different if Frankfurt had more GA traffic with latest Garmin glass cockpits… Airlines and airliners are very conservative regarding new technologies. At my home base, the ILS of the main landing runway 25 is on maintenance for many months to come with frequent outages. On the ATIS, they say “state on first contact which kind of approach you request – VOR or RNP (= GPS for most of us)”. 80% of the airline traffic requests the VOR approach while 80% of GA traffic (including all the flying school planes which have GNS 430 units) ask for the RNP. It will take many more years until that will change.

EDDS - Stuttgart

I don’t think there is much in GA avionics supporting GBAS – if any – that’s more for Cat II and III.

GA avionics tend to do SBAS = Satellite-Based Augmentation System = WAAS (US) or EGNOS (Europe)

Last Edited by Cobalt at 23 Apr 22:46
Biggin Hill

From here

Mooney_Driver wrote:

It may also become a capacity problem: Airports tend to have massive capacity reductions while under LVP and the last thing they would need in such a case is a 70 kts approach speed airplane between the 150 kts airliners in a CAT II/III setting.

How about approving Cat2 operations outside places without Cat2 ILS, problem solved?

Anyone who keeps hand flying LPV guidance bellow 200ft would notice it works fine down to 50ft, even better with SVT, however, it will result in load of crashes if the runway does not have Cat2 physical data (60m wide & 4km long with lights)

It’s a very narrow scope: Cat2 LPV private operations in Cat2 RWY without serviceable Cat2 ILS antenna

Last Edited by Ibra at 09 Feb 11:57
Paris/Essex, France/UK, United Kingdom

I don’t think there is CAT 2 LPV but @lbra you may be saying it in jest :)

Even with differentiated SBAS signals am not sure I want to trust GPS below 200 feet system minima – ionospheric and temperature corrections etc

Oxford (EGTK), United Kingdom

RobertL18C wrote:

I don’t think there is CAT 2 LPV but @lbra you may be saying it in jest :)

That’s not quite what he said. He said continued flight using LPV guidance below 200 ft, which is perfectly legal if you have the runway environment in sight.

Even with differentiated SBAS signals am not sure I want to trust GPS below 200 feet system minima – ionospheric and temperature corrections etc

Isn’t GBAS is supposed to be useable (eventually) for Cat III autoland?

ESKC (Uppsala/Sundbro), Sweden

RobertL18C wrote:

I am not sure I want to trust GPS below 200 feet system minima

I do the glance at runway at DA (+200ft), decide to continue before reverting back to keep flying LPV guidance, it just magically works, I don’t ever recall a single time when it has gone bad or I get something off center-line? I even done it few times with low pass along the whole runway dead on center-line level at 50ft all the way for 3km to the opposite runway end, as long as you refrain from pressing SUSP: the signal is dead in middle and smooth as silk at any height and at any point of the runway, even when it switches between angular & lateral after TDZ…pretty serious stuff, I would say

Do I trust it absolutely YES, can I legally use it absolutely NO !

Yes there are zillion of error sources in GPS-W (including errors from Sunyaev–Zeldovich effect) but I have yet to see more that 5m error from the center-line…

Last Edited by Ibra at 09 Feb 13:51
Paris/Essex, France/UK, United Kingdom
Sign in to add your message

Back to Top