GPS approaches with VNAV vertical guidance

Another issue is that right now only airlines can really make use of this
stuff anyway, since relatively few people are flying behind v2 GNS-480s.
This is why Jane Garvey said in her AOPA speech that it's important for
pilots to go out and get new equipment that can make use of this. Of course,
I'd like to see her agency help by making it easier to certify and install
such equipment. There's no reason it should cost $15,000 to do so.



Jane Garvey? ;-)

The airlines are NOT making use of WAAS. They have basically told the FAA to
take WAAS and shove it. Almost no airline aircraft have WAAS. In fact, all the
aircraft produced prior to the early 1990s don't even have GPS unless they have
been upgraded (a very expensive upgrade for that type of aircraft certification
process).

The airlines are in the financial fight of their corporate lives. They couldn't
care less about WAAS and LPV.

wrote in message ...


The airlines are NOT making use of WAAS. They have basically told the FAA
to
take WAAS and shove it. Almost no airline aircraft have WAAS. In fact,
all the
aircraft produced prior to the early 1990s don't even have GPS unless they
have
been upgraded (a very expensive upgrade for that type of aircraft
certification
process).


No, but they do use LNAV/VNAV with FMS-derived VNAV. Northwest and a few
others got approval for this a few years back IIRC and that's why those new
descent profiles started popping up on Jepp plates. It's also why the new
approaches are all called RNAV and not GPS.

-cwk.

C Kingsbury wrote:

wrote in message ...


The airlines are NOT making use of WAAS. They have basically told the FAA
to
take WAAS and shove it. Almost no airline aircraft have WAAS. In fact,
all the
aircraft produced prior to the early 1990s don't even have GPS unless they
have
been upgraded (a very expensive upgrade for that type of aircraft
certification
process).


No, but they do use LNAV/VNAV with FMS-derived VNAV. Northwest and a few
others got approval for this a few years back IIRC and that's why those new
descent profiles started popping up on Jepp plates. It's also why the new
approaches are all called RNAV and not GPS.

No doubt about it. Most of them use their GPS-equipped aircraft for LNAV/VNAV
as an ILS backup at major airports and as primary IAPs at a few airports. But,
that has everything to do with GPS and nothing to do with WAAS.

wrote:



Another issue is that right now only airlines can really make use of this
stuff anyway, since relatively few people are flying behind v2 GNS-480s.
This is why Jane Garvey said in her AOPA speech that it's important for
pilots to go out and get new equipment that can make use of this. Of course,
I'd like to see her agency help by making it easier to certify and install
such equipment. There's no reason it should cost $15,000 to do so.




Jane Garvey? ;-)

The airlines are NOT making use of WAAS. They have basically told the FAA to
take WAAS and shove it. Almost no airline aircraft have WAAS. In fact, all the
aircraft produced prior to the early 1990s don't even have GPS unless they have
been upgraded (a very expensive upgrade for that type of aircraft certification
process).

True, they want LAAS at just the airports that they use.


Matt

Matt Whiting wrote:



True, they want LAAS at just the airports that they use.

Correct, LAAS, not WAAS.

"Roy Smith" wrote in message
...
In article ,
(Doug) wrote:

What's a little silly is that there's also an ILS-16 which gets you the
standard 200 & 1/2, so except as a contingency against the ILS being
OTS, having the LNAV/VNAV approach doesn't buy you anything. The big
payoff is still in the future, when the FAA starts publishing LNAV/VNAV
approaches to runway ends (and airports) which aren't already served by
ILS or other ground-based approaches.


Our local "big" airport has four ILS's to 200 ft DH, and various VOR, GPS,
and NDB approaches. There are four new RNAV(GPS) approaches: for each
runway (36L and 36R), there are two of these approaches (Y and Z). In each
case, Z has LNAV and LNAV/VNAV minima, and Y has LNAV only. The Y and Z
approaches have the same IAFs, IF, FAFs, and MAPs. The Z LNAV MDA is 545
ATDZE, the Z LNAV/VNAV MDA is 325 ATDZE, a 220 ft advantage. But on the Y
approach, the LNAV MDA is 325 ATDZE. The only difference between the
approaches is that Y has a stepdown fix after the FAF, which is apparently
avoided by VNAV. Heck, with a 325 ft ATDZE MDA with LNAV alone, I sure
don't need VNAV, if it just gets me to the same DA. And 325 is pretty darn
good.

It's curious to me that two approach plates were published for Y & Z, rather
then combining them and noting the stepdown fix as applicable to LNAV only.
Maybe it made for too much chart clutter.

I hope we get the corresponding approaches for 18L and 18R.

For a while, LNAV procedures with a stepdown were not allowed to be
combined with a LNAV/VNAV. If you wanted a stepdown to get lower LNAV
MDA, you had to create a separate procedure. That rule has since been
rescinded, so you'll see future combined LNAV/VNAV and LNAV with a
stepdown if appropriate. In the meantime, the "X" and "Y" procedures
will remain as they are until amended, but amending them is not a priority.

JPH

Stan Prevost wrote:
"Roy Smith" wrote in message
...


Our local "big" airport has four ILS's to 200 ft DH, and various VOR, GPS,
and NDB approaches. There are four new RNAV(GPS) approaches: for each
runway (36L and 36R), there are two of these approaches (Y and Z). In each
case, Z has LNAV and LNAV/VNAV minima, and Y has LNAV only. The Y and Z
approaches have the same IAFs, IF, FAFs, and MAPs. The Z LNAV MDA is 545
ATDZE, the Z LNAV/VNAV MDA is 325 ATDZE, a 220 ft advantage. But on the Y
approach, the LNAV MDA is 325 ATDZE. The only difference between the
approaches is that Y has a stepdown fix after the FAF, which is apparently
avoided by VNAV. Heck, with a 325 ft ATDZE MDA with LNAV alone, I sure
don't need VNAV, if it just gets me to the same DA. And 325 is pretty darn
good.

It's curious to me that two approach plates were published for Y & Z, rather
then combining them and noting the stepdown fix as applicable to LNAV only.
Maybe it made for too much chart clutter.

I hope we get the corresponding approaches for 18L and 18R.

Thanks.

"J Haggerty" wrote in message
news:fjBhd.93062$tU4.67667@okepread06...
For a while, LNAV procedures with a stepdown were not allowed to be
combined with a LNAV/VNAV. If you wanted a stepdown to get lower LNAV MDA,
you had to create a separate procedure. That rule has since been
rescinded, so you'll see future combined LNAV/VNAV and LNAV with a
stepdown if appropriate. In the meantime, the "X" and "Y" procedures will
remain as they are until amended, but amending them is not a priority.

JPH

Stan Prevost wrote:
"Roy Smith" wrote in message
...


Our local "big" airport has four ILS's to 200 ft DH, and various VOR,
GPS, and NDB approaches. There are four new RNAV(GPS) approaches: for
each runway (36L and 36R), there are two of these approaches (Y and Z).
In each case, Z has LNAV and LNAV/VNAV minima, and Y has LNAV only. The
Y and Z approaches have the same IAFs, IF, FAFs, and MAPs. The Z LNAV
MDA is 545 ATDZE, the Z LNAV/VNAV MDA is 325 ATDZE, a 220 ft advantage.
But on the Y approach, the LNAV MDA is 325 ATDZE. The only difference
between the approaches is that Y has a stepdown fix after the FAF, which
is apparently avoided by VNAV. Heck, with a 325 ft ATDZE MDA with LNAV
alone, I sure don't need VNAV, if it just gets me to the same DA. And
325 is pretty darn good.

It's curious to me that two approach plates were published for Y & Z,
rather then combining them and noting the stepdown fix as applicable to
LNAV only. Maybe it made for too much chart clutter.

I hope we get the corresponding approaches for 18L and 18R.

(Doug) wrote in message om...
With all the talk about the GNS80 and the Garmin 430 having VNAV and
LAAS capability, I would like to know something. Are there any actual
approaches in use that one can fly, today, that use these features? Do
you get vertical guidance from GPS derived altitude or is it vertical
guidance from altimeter derived altitude? Where are these approaches?

Doug,

I assume you meant WAAS, not LAAS. I'm showing 261 WAAS VNAV
approaches as of August 5th update cycle. 237 are LNAV/VNAV minima and
24 are LPV minima. AVN's Website has good info:

http://www.avn.faa.gov/index.asp?xml=index

Regards,
Jon