GPS Approach - Bronnoysund ENBN

[malabo]

Anybody got the GPS LPV Approach Plate for Bronnoysund, Norway. ENBN. I hear some of the commercial carriers are using it with their DHC-8. Somewhat progressive.

malabo

[BestGlide]

I guess the approach plate for the GLS-approach (or SCAT-1 if you want) will be found here after a while: http://www.ippc.no/norway_aip/current/AIP/AD/ENBN/enbn.html

If I remember correct, there will be installed equipment at 6 more airports in Norway in 2008, necessary to fly GLS-approaches.

[TuckUnder77]

No, it won't appear on IPPC or in AIP Norwegen.

The SCAT-1 approaches are not for public use.

[malabo]

Thanks BestGlide,

It wasn't there yet, but I found it as an AIP SUP at <https://www.ippc.no/ippc/display_pdf_or_url_servlet?origfilename=EN_Sup_2007_009_en.p df>

Interesting approach compared to the similar LPV approaches in the US. Variable DH dependent on glideslope angle? Also the missed dependent on VOR DME instead of keeping the autopilot coupled to GPS looks a little odd, but in reality I suppose any good FMS will just chug along in GPS anyway. In the US and Canada they use WAAS, but it looks like Norway got tired of waiting for the EGNOS satellites fiasco to resolve itself and simply got the technology for a localized precision addition to the GPS. That innovation has huge implications worldwide.

I see in the US there are now quite a few LPV approaches going down to full Cat 1 ILS limits of 200' DH.

Hey Tuck, the world only spins one way. SCAT-1 will be like any other improved instrument approach instrument procedure - restricted initially, then public. But it will have to be coded into everyone's FMS database, certainly all the Universals, and cleared for the approach gives you the airspace. Don't forget the accident using conventional approach aids that led to this experiment. Nobody is going back to LF range approaches either. And when was the last time any of you guys hand-flew an NDB approach from a bearing pointer - considered an emergency situation these days.

malabo

[Vso]

The SCAT 1 system, is a joint venture between Avinor and Wideroes. The system might be good, bur it will only be used by Wideroes, and maybe some other operators with Universal FMS'es.

The "ground" box has to be made by Honeywell.

So, if You have a Honeywell box on the ground, and Universal FMS in the air it might be used.

They should never locked themselves to use only theese brands.

They should have requested an capasity instead:

-FMS shall recieve and use differential GPS information.
-FMS shall be able to compute vertical navigation.
-FMS shall have a database with relevant GLS approaches etc. etc.

I think this Norwegian system is a failure, the international community will never accept to be dependant on single manufacturers. (I hope)
The government and WF have used more than 100 millions on this...

What is Your view?

[sega]

Variable DH dependent on glideslope angle?

Minima varies depending on the angle of the missed app.

[malabo]

The AIM magazine I am reading says there are 25 more airports in Norway getting this kind of approach. You are correct that there are some unusual aspects to this particular approach design that will cause some unnecessary limitations. Perhaps the Norway regulators are trying this as an experiment and (like the 400' DH limitation) are keeping some additional restrictions on it until they are satisfied it is safe.



There are more LPV and LAAS (SCAT-1) or WAAS capable FMS/GPS equipment available that everyone here is now installing. In fact, you can no longer even buy a non-WAAS Garmin 530, only the newer LPV capable 530W. The old stuff ends up on eBay for whatever you can get for it.


malabo

Sega, just saw your note on missed approach angle and the approach makes more sense now. I see that missed approach minimum climb gradient is referred to as OCA(H). Never seen this before being Jepp guy myself. Standard on this side of the Atlantic is 1:40 OCS for airplanes and 1:20 OCS for helicopter. So a 3 degree OCA (1:20 OCS) is about 300' per nm climb, and the 4 degree is 400' per nm. Your typical 120 knot aircraft would need an OEI climb rate of 800fpm to meet the 4 degree requirement and be able to use the lower limits once the 400' DH restriction is lifted.

[Pov]

https://www.ippc.no/ippc/display_pdf_or_url_servlet?origfilename=EN_Sup_2007_009_en.p df

[Icenor]

Im somewhat confused by this new system. On one side Im reading that Norway is the first country in the world to use this system and on the other side I'm watching instructinal videos of GPS approaches with LPV done in the US.

Is it two different systems? As far as I know the US system is open to the public, but does anyone know if the same goes for the norwegian version? And if not, why?

[Guttn]

Icenor, it`s not that confusing. GPS and GLS/SCAT-1 approaches are both based upon satellite navigation :ok:. Some of the differences are, if memory serves correct, that GLS/SCAT-1 approaches have more preciscion than the normal GPS approach. Mainly due to a required ground station at the field, in addition to the required GPS satellites. And due to the higher presiscion, the DH can be lower:D, all the way down to 200`, which is standard ILS CAT-1 minima. The S in SCAT-1 means Special:ok:. So you can call it a GPS based ILS if you want:}

[Icenor]

Yeah I get that. But my confusion comes from hearing about GLS for instance in the article in Flynytt called "GLS innført i Norge - først i verden":
http://0o2471.net//3489.jpg


Then reading about WAAS on wikipedia were it states:

"On July 10, 2003, the WAAS signal was activated for general aviation, covering 95% of the United States, and portions of Alaska offering 350 ft minimums."

It seems to be the same system only different manufactures and as far as I know the US, EU, Japan, etc are all developing their own system based on their own satellites. And thats ok, I get that, but my questions are:

1. Why are they calling the GLS at Brønnøy the first in the world, is it that much different and better?
2. Why wont the Norwegian system be open to GA like in the US?
3. When they expand the system in Norway, and if its open to the public, will you be able to use it with a GNS 430W?

[Vso]

WAAS is WIDE Area Augmentation System, systems on the ground checks the reported gps pos against the excactly known pos, and sends a correction signal back to the satelites. The satelites broadcast an correction factor, augmentation in a wide area. The signal is like: Correct 27 meters 320 deg, in a wide area.

LAAS is LOCAL Area Augmentation System, a gps reciever at or close to the airport checks the reported gps pos against the excact known pos, and sends an omnidirectional correction signal to airplanes with LAAS capable recievers. The signal is like: Correct 25 meters 280 deg, in this area.

With WAAS and LAAS it is possible to fly ILS like GPS approaches. The GPS/FMS unit creates a computed glideslope.

With WAAS and LAAS, all equipment that are approved to the correct specifications can be used. Many brands, like Garmin, Bendix King etc. (Competition)

With SCAT-1, the Norwegian Government and Wideroes have agreed upon creating a system like LAAS, but it is locked to certain brands, like Honeywell for ground stations, and Universal Avionics in the aircraft. (No competition for avionis manufacturer or Wideroes.)

That is it basically. I doubt that the system will be implemented by other operators, due to the limited avionics that can be used. To bad actually, since the LAAS/Open SCAT systems is the future.

[Crossunder]

Icenor:

SCAT-1 includes a glide path, standalone GPS only has the lateral element plus maybe some sort og barometric VNAV if your FMS is capable of it. Hence, SCAT-1 is a precision aproach (Special CAT-1), offering a potential DH of 200ft. GPS approaches are non-precision app. with a higher minimum DH.

GPS aproaches are widely in use around the world, but SCAT-1 is, for now, unique to Norway. G/A aircraft can also make use of these approaches, but you´d have to invest a stupid amount of money in new NAV equipment...

The main advantage is not necessarily, in my opinion, the lower DH, but the Glide Slope guidance on a steep approach. This will, perhaps, minimise the risks involved in dive-and-drive steep-angle NPAs.

[Icenor]

Yeah I get that, but if you check out WAAS it also provides vertical navigation for precision approaches and as far as I know its been around for some time and already in use by general aviation in the US.

But Vso did a desent job in explaining it. Same but different :ok:
I can't really see the wisdom of the way it's being done here in Norway though, except if your goal is to maintain the advantage that Widerøe would have over other operators. And it kinda screws us in GA too if the system becomes open to the public.

[Guttn]

It is really just a question of getting the correct avionics (dual fms of a certain brand), doing the training and then putting it into use:ok:. Of course this isn`t free. If it was made specifically so that WF would have a great advantage when time comes to applying to the government to fly the given routes should be no more than speculation as this process has taken some 10 years or so to complete:ugh:. It should be seen as a great improvement with regards to safety during approaches to these small airports, some of which still only have NDBs to specific runways :bored::eek:.

Icenor, why do you think a new type of approach will screw it up for the GA folks? BNN also has a LOC approach as well as a VOR approach (actually 2 - 1 from each direction N/S approx).

[malabo]

I also have to question the "all or nothing" approach of what is being done in Norway. If this approach was in the US, you would have several different limits depending on whether or not you had the vertical guidance, and the LAAS accuracy augmentation. In simple terms, this approach replicates an LPV approach, but makes no provision for either a VNAV or LNAV which are normally integrated into the approach design at the same time.

Further, since the missed approach must be done from the VOR, there is no additional economic benefit from removing the ground-based navaids. Add to that the apparent requirement for dual FMS and you've successfully priced it out of any GA application and many other commercial aircraft. Some aircraft are only equipped with a single FMS and a second install would be prohibitive, especially if it is the big specialized UNS box.

General aviation has more relaxed equipment standards that commercial carriers. In North America, a Cessna 182 with a single Garmin 530W can file IFR to a GPS-only destination and carry a GPS-only alternate - providing it has the WAAS capability and prediction. The reliability of the non-precision level GPS approach (which has lower limits that the current Bronnoysund approach), is well over 99% - better than the reliability of the navaids.

Anyway, I find it strange that simple "T" pattern GPS approaches don't already exist everywhere in Norway. You must love those NDB's there.

malabo

[Icenor]

Icenor, why do you think a new type of approach will screw it up for the GA folks?

You kind of answered your own question with this:

It is really just a question of getting the correct avionics (dual fms of a certain brand)...

Just compare the price/size of a dual FMS and a simple thing like the GNS 430W that is WAAS capable.

[Guttn]

Icenor, I was thinking GA = VFR, since that is usually the case in Norway due to icing conditions, climb grdients and so on, but of course you`re right - GA also use IFR:ok:.

Malabo, yup we sure love them NDBs :eek:! Personally I don`t understand why Norway didn`t go for the MLS system when it was first introduced:confused:. Curved approaches as preciscion missed approaches could have been the norm for about 2 decades now, but alas, we just cn`t seem to decommission the eloved NDBs yet. :ugh::{. And as we speak, we only have 3, maybe 4, GPS approaches available. Lots of politics involved in the deciscionmaking process, whereas flight safety to some extent may hve been compromised by economics :yuk::=. But we`re finally catching up, albeit at a very very slow pace:}