Rob, have you been in LOWI lately? Sim or RL? Anyway section 2.19 of textual Austrian AIP - LOWI Unfortunately I don't have at hand a video where it can be clearly seen, only when references can be heard from cockpit chatter, but unfortunately it is in Slovak... Now I don't want to sound unnecessarily harsh, but should I probably send the CAA people who approved that procedure to go read that link?

Real life is more than 12 years ago (B737). Sim about 2 months (EDIT:pmdgB737NGX). I have no idea what you are talking a out. What does is say in the AIP?

 

 

What CAA procedure are you talking about?

 

Are you a real world pilot?

If so, ok lets discuss this politely (so far we are ok,but....).

If not, then thrust me, I know what I am talking about.

That does not mean I am never wrong....but I know what LOCDME means!

 

On a side note...due to some construction they have a special TEMPO eeeh NDB I think. Saw it in the NOTAMS recently. Will look at it myself cause anything new into LOWI is bound to be interesting.

Now I don't want to sound unnecessarily harsh, but should I probably send the CAA people who approved that procedure to go read that link?

 

Er, why? If a VOR approach is all that's published then that's what you have to follow regardless of how awesome your ANP may be.

 

 

Check out the position error!! If the Shuttle's inertial nav systems were not good enough...

 

That's a really, really poor analogy.  The space shuttle first flew in 1981.  RNP and associated ANP weren't even implemented at that point, but you'd see that ANP was pretty poor in that video's situation if it had been.

 

I'm no expert on the Shuttle, but I think its only reference was 3 IMUs.  Given your average position drift for those type of units, and the average length of shuttle missions (which means it picked up several days worth of drift), that's actually pretty good accuracy for IMU alone.

 

Yes, IMU - Inertial Measurement Units.

 

Now, when I first heard about GPS and all that taking over and VORs/NDBs eventually dying off, I had similar opinions to your own until I actually sat down and thought about it.  Most modern aircraft utilizing RNP approaches incorporate several different systems to coordinate a single position.  The 777, as an example, gets position data from IRUs, GPS sensors and ground station updating.  It's taking the original position-by-ground-station concept and making it stronger and more precise by evaluating those positions against other computed locations (IRU and GPS).

 

It's actually very highly accurate, despite not being directly "tied to the ground," which seems to be your main argument against it.  As an example, here's the ILS into LGA versus the RNAV RNP into JFK:

(Source FAA.gov - public domain)

 

Granted, a lot of the "fuzz" on the LGA approaches is vectors up to the point of the ILS intercept, but you can see several overshoots and other anomalies that are not present on the RNP tracks.  There also isn't much variation in those tracks, either.  While the concept might seem somewhat unnerving, without a specific "tie" to a ground based navaid, provided the system maintains adequate ANP, you're just fine.  For what it's worth, adequate ANP for an approach is often down to 0.3nm (1800').  In other cases, where it's very important, that's dropped to 0.1 (600').  Remember that those are max tolerances, too.  That kind of lateral precision really isn't available using VORs and NDBs.

 

 

 

Innsbruck LOC/DME has [vertical guidance]. Of course this is a special case.

 

This is true, but you've already mentioned it: it's a special case.  The generally accepted definition of a non-precision approach is one without vertical guidance.  Just about all syllabi define it as such.

 

 

 

Come on now....a LOC/DME per definition has no Glide Slope = no vertical guidance. Not in LOWI either.
If it had a GS it would be called an ILS!

 

It actually has vertical guidance.  Check the chart out.

 

The reason it's not listed as an ILS is that it doesn't meet the design and obstacle-free requirements of one.  Honestly, a different name would be better, like LDA/GS or something like that.  We use a few of those in my area (DCA and ROA, notably).

 

 

 

Our 777s are certified Lnav/Vnav (ofcourse) and we SHALL cross check when we use Lnav/Vnav to fly a VOR/VORDME/LOC/LOCDME etc.

An Approach needs to be designed as an RNAV approach or an RNPRNAV approach to not have to cross check with needles.
That is why I said read the link....I explained it before.

 

 

Now I don't want to sound unnecessarily harsh, but should I probably send the CAA people who approved that procedure to go read that link?

 

Looks like people are getting into a little greyviation (yes, I invented a term, and if it catches, I'm expecting this timestamped post helps pin it back to me B) ) here.  A good amount of regulation is in greyviation.  If an airline's approved ops allows for the use of LNAV/VNAV without monitoring because they satisfied the regulatory agency's requirements, then they don't need to crosscheck with raw data.  Similarly, if you look at EFBs, they need to be compliant and specifically listed in the airline's approved ops for use.

 

There's some contradicting of the base regulations that can be done in approved airline ops, provided the FSDO allows it.

 

Stepping back to black and white aviation, though, the stance is a little more clearer.  Here's the FAA stance:

Q. I have heard about flying an “overlay” approach, and that it is basically flying a VOR or other approach, but using the GPS instead of the VOR or ADF. Can I just use the GPS instead of the VOR?

A. No. Overlay approaches can use GPS instead of the primary designated navigational aid, but the approach must be designated for GPS and be in the current aircraft database. For example, it must say “VOR or GPS RWY 16.” You cannot just use GPS in lieu of VOR, Automatic Direction Finder (ADF) or other navigational source naming the approach. You can, however, use GPS to determine waypoints during the approach.

 

So, in certain terms you're both right, but at the base level of regs you need to display the raw data if the approach just states "VOR" or "NDB" with no mention of GPS in the title.

If an airline's approved ops allows for the use of LNAV/VNAV without monitoring because they satisfied the regulatory agency's requirements, then they don't need to crosscheck with raw data.  

Very good point and very good post Kyle! Great info :-)

Our SOP make us crosscheck.

 

 

It actually has vertical guidance.  Check the chart out.

 

The reason it's not listed as an ILS is that it doesn't meet the design and obstacle-free requirements of one.  Honestly, a different name would be better, like LDA/GS or something like that.  We use a few of those in my area (DCA and ROA, notably).

 

Shoot you guys are right....small print...but it has a 4 degrees GS.

I could not remember from more than 12 years ago and missed the small print.

Ok pretty embarassing :-(

 

Hey FABO you still there?

I apologize.

 

 No. Overlay approaches can use GPS instead of the primary designated navigational aid, but the approach must be designated for GPS and be in the current aircraft database. For example, it must say “VOR or GPS RWY 16.” You cannot just use GPS in lieu of VOR, Automatic Direction Finder (ADF) or other navigational source naming the approach. You can, however, use GPS to determine waypoints during the approach.[/size][/font][/color]

 

So, in certain terms you're both right, but at the base level of regs you need to display the raw data if the approach just states "VOR" or "NDB" with no mention of GPS in the title.

And that was the kind of approach I am talking about when I meant cross checking is required.

 

 

Ok pretty embarassing :-(

 

haha - Not too bad.  How about claiming something is a navdata issue and having the developer of said navdata chime in and put you in your place because you were too lazy to read the actual issue?

 

Yep...

http://forum.avsim.net/topic/423828-possible-fmc-bug/

 

:blush2: oops...

 

It happens.

haha - Not too bad.  How about claiming something is a navdata issue and having the developer of said navdata chime in and put you in your place because you were too lazy to read the actual issue?

 

Yep...

http://forum.avsim.net/topic/423828-possible-fmc-bug/

 

:blush2: oops...

 

It happens.

Looked at that thread, ok I feel better now, thx :-) lol

 

 

What does is say in the AIP?

 

It's actually the position, frequency and identification of the GP antenna. I see you found a reference somewhere, so this can be closed.

 

 

What CAA procedure are you talking about?

IIRC it was included a part of RNP package. The airline in question was a pioneer in introducing RNP to Europe. 

 

 

If so, ok lets discuss this politely (so far we are ok,but....).
If not, then thrust me, I know what I am talking about.
That does not mean I am never wrong....but I know what LOCDME means!

 

The trouble with aviation is the variation... Past your own airline, one can never be sure of some things...

Though I feel it is good that this is shown. I have heard my share of "But over at Seagle..."

 

 

This is true, but you've already mentioned it: it's a special case.  The generally accepted definition of a non-precision approach is one without vertical guidance.  Just about all syllabi define it as such.

 

I do think it is time the syllabi were changed... I have seen some materials gradually changing. The definition I am working with is something along of "A precision approach is an approach that will bring the airplane to a position such as no other changes in horizontal or vertical track are required to land on the runway".

 

Ultimately, it boils down to what they want you to circle on a test :(

 

 

Honestly, a different name would be better, like LDA/GS or something like that.  We use a few of those in my area (DCA and ROA, notably).

 

I suppose that is true.

 

 

Looks like people are getting into a little greyviation (yes, I invented a term, and if it catches, I'm expecting this timestamped post helps pin it back to me  )

 

That is a nice word. I will endeavour to use it

 

 

So, in certain terms you're both right, but at the base level of regs you need to display the raw data if the approach just states "VOR" or "NDB" with no mention of GPS in the title.

 

Base regs, yes - that is why I said from the beginning that you would need certification to run such approaches without crosscheck. Fortunately it is way easier to get in flightsim

 

 

Hey FABO you still there?
I apologize.

 

No problem. One can only remember or know so much... no shame in admitting you let go of something to make room for something else.

Ultimately, it boils down to what they want you to circle on a test :(

 

Ain't that the truth; and sometimes the one they want isn't even technically correct.

 

 

I do think it is time the syllabi were changed... I have seen some materials gradually changing. The definition I am working with is something along of "A precision approach is an approach that will bring the airplane to a position such as no other changes in horizontal or vertical track are required to land on the runway".
 
Ultimately, it boils down to what they want you to circle on a test

 

haha - yeah, exactly.  Heck, I think we finally killed references to LORAN on PPL written tests.  Granted, I flew a plane with LORAN when I was first doing my PPL training, but it being dropped in favor of more emphasis on GPS is somewhat promising.

 

...and you're definitely right.  It's time the syllabi changed, in addition to the agency handling of the approach precision.  RNAV approaches with vertical guidance seem to be in greyviation, too, in terms of how the agency treats them.  Currently, they're semi-precision.  They're not non-precision, but they're not precision, and the only time you get CAT I - like minimums is when it's LPV.

 

 

 

That is a nice word. I will endeavour to use it

 

Hooray for support!

...or is it huzzah?

 

 

 

Base regs, yes - that is why I said from the beginning that you would need certification to run such approaches without crosscheck. Fortunately it is way easier to get in flightsim

 

haha - yep.  Just like my clearance into the FRZ to land a Cessna at DCA and live to talk about it.

Not to digress too much, but whilst the Shuttle was on orbit, she used both ground based (yes, you read correctly) stations in the form of TACAN, and a star tracking system pioneered on the SR-71. The star tracker system alone is mind-blowing in terms of the accuracy achievable.

 

Best regards,

Robin.