Help understanding Aspen VOR/DME approach

SimGuy wrote:
The plate is here-

http://www.airnav.com/depart?http://.../05889VDGC.PDF

While trying to fly the approach in the sim I flew to the MAP with
relative ease but had trouble getting low enough to make the runway
without getting too hot. Looking at the plate it seems a drop of 2380'
must be made between MAFMU and the runway in a lateral distance of
1.4NM, this is a descent angle of 15 degrees!

Could someone please confirm this or help with my interpretation of
the chart. I am a PP beginning instrument training.

TIA

Having actually flow this approach in a real airplane, a T182RG. It is a
real SLAM DUNK. We ended up circling to get down. Spoilers would be a
huge help.

Michelle

Peter R. wrote:
Sam Spade wrote:

Most of the birds that can fly this approach when it is needed have LNAV
and moving maps. They don't tune the missed approach LOC.

Wouldn't it be a requirement that the missed approach LOC be tuned and used
as primary navigation by all pilots (serious question, as I am not at all
familiar with IFR regulations as they pertain to 135 or 121 operations).

No such requirement. Not even sure you need one of you've got GPS
(provided this isn't your alternate).

Peter R. wrote:
Sam Spade wrote:


Most of the birds that can fly this approach when it is needed have LNAV
and moving maps. They don't tune the missed approach LOC.


Wouldn't it be a requirement that the missed approach LOC be tuned and used
as primary navigation by all pilots (serious question, as I am not at all
familiar with IFR regulations as they pertain to 135 or 121 operations).


Because the LOC is not part of a final approach segment, the limitation
that RNAV (GPS) cannot be used to substitute for the LOC does not apply
in that sense. The standard practice would be to revert to LNAV for the
missed approach procedure, irrespective of underlying nav aids. In the
case of 121 or 135 the FAA *could* prohibit this at Aspen if they chose
to. I doubt they would, or have.

The protected airspace on each side of that missed approach back course
is much larger than the protected airspace for a LOC (front or back
course) final approach segment.

Using the Garmin 430 or 530 as an example, the workload during the
missed approach at Aspen would be very high to revert to the missed
approach back course LOC as opposed to using LNAV (RNAV/GPS).

A common misunderstanding I have seen from IFR students is the concept
that transition to visual begins at the MAP. MAP is where the missed
approach begins; it is not where the visual segment begins. You should
be in visual well prior to the MAP, otherwise a normal descent and
landing may not be possible. This is why some approaches designate a
VDP (Visual Descent Point), a point from where you can make a 3-deg
descent to the runway.

Aspen is not the only example. There are plenty of examples where the
MAP is on top of the runway (or even past the runway), so a straight-in
landing is clearly not possible from that point.



SimGuy wrote:
The plate is here-

http://www.airnav.com/depart?http://.../05889VDGC.PDF

While trying to fly the approach in the sim I flew to the MAP with
relative ease but had trouble getting low enough to make the runway
without getting too hot. Looking at the plate it seems a drop of 2380'
must be made between MAFMU and the runway in a lateral distance of
1.4NM, this is a descent angle of 15 degrees!

Could someone please confirm this or help with my interpretation of
the chart. I am a PP beginning instrument training.

TIA

SimGuy wrote:
The plate is here-

http://www.airnav.com/depart?http://.../05889VDGC.PDF

While trying to fly the approach in the sim I flew to the MAP with
relative ease but had trouble getting low enough to make the runway
without getting too hot. Looking at the plate it seems a drop of 2380'
must be made between MAFMU and the runway in a lateral distance of
1.4NM, this is a descent angle of 15 degrees!

Could someone please confirm this or help with my interpretation of
the chart. I am a PP beginning instrument training.

TIA

On 6 Aug 2006 09:08:33 -0700, "Andrew Sarangan"
wrote:

A common misunderstanding I have seen from IFR students is the concept
that transition to visual begins at the MAP. MAP is where the missed
approach begins; it is not where the visual segment begins. You should
be in visual well prior to the MAP, otherwise a normal descent and
landing may not be possible. This is why some approaches designate a
VDP (Visual Descent Point), a point from where you can make a 3-deg
descent to the runway.

Aspen is not the only example. There are plenty of examples where the
MAP is on top of the runway (or even past the runway), so a straight-in
landing is clearly not possible from that point.



I must admit this has confused me. Is it the case that once I have the
field in sight I can dip below the minimums on the chart?

Absolutely! Once the field is in sight, with enough flight visibility,
you can descend below the minimum (FAR 91.175). If you couldn't, many
nonprecision approaches would be simply unflyable.


SimGuy wrote:

SimGuy wrote:
The plate is here-

http://www.airnav.com/depart?http://.../05889VDGC.PDF

While trying to fly the approach in the sim I flew to the MAP with
relative ease but had trouble getting low enough to make the runway
without getting too hot. Looking at the plate it seems a drop of 2380'
must be made between MAFMU and the runway in a lateral distance of
1.4NM, this is a descent angle of 15 degrees!

Could someone please confirm this or help with my interpretation of
the chart. I am a PP beginning instrument training.

TIA

On 6 Aug 2006 09:08:33 -0700, "Andrew Sarangan"
wrote:

A common misunderstanding I have seen from IFR students is the concept
that transition to visual begins at the MAP. MAP is where the missed
approach begins; it is not where the visual segment begins. You should
be in visual well prior to the MAP, otherwise a normal descent and
landing may not be possible. This is why some approaches designate a
VDP (Visual Descent Point), a point from where you can make a 3-deg
descent to the runway.

Aspen is not the only example. There are plenty of examples where the
MAP is on top of the runway (or even past the runway), so a straight-in
landing is clearly not possible from that point.



I must admit this has confused me. Is it the case that once I have the
field in sight I can dip below the minimums on the chart?

When you come to Aspen, stop in Denver and pick up a CFII who
knows the approach to Aspen *really well*.

And yes, everything on the plate is real. As for circling minimum...
let me *strongly* suggest you get the Denver sectional or
take a look at the area on aeroplanner. Don't rely exclusively
on the IFR chart. If you do, you'll be unprepared.

In article kH9Bg.513$0F5.178@fed1read04, Sam Spade wrote:
At Aspen, circling around the airport is very risky business.

Unless you're at 20,000 ft. Ok, maybe 18K.

-----Original Message-----
From: Sam Spade ]
Posted At: Saturday, August 05, 2006 6:19 PM
Posted To: rec.aviation.ifr
Conversation: Help understanding Aspen VOR/DME approach
Subject: Help understanding Aspen VOR/DME approach

Paul Tomblin wrote:
In a previous article, said:

The plate is here-
http://www.airnav.com/depart?http://204.108.4.16/d-
tpp/0608/05889VDGC.PDF

While trying to fly the approach in the sim I flew to the MAP with
relative ease but had trouble getting low enough to make the runway
without getting too hot. Looking at the plate it seems a drop of
2380'
must be made between MAFMU and the runway in a lateral distance of
1.4NM, this is a descent angle of 15 degrees!


Well, yes, if you don't see the runway until the MAP and then want
to
land
on the runway ahead, you will have a very steep descent. But there
are
two factors mitigating that:
- you might see the runway earlier and
- it's a circling approach, so you can circle around airport to
descend
if
you need to.


At Aspen, circling around the airport is very risky business.

No kidding!! Isn't that why we all learned steep-turns-about-a-point?
Even the 360-overhead would be thrilling at Aspen.

-----Original Message-----

From: Blanche Cohen ]

Posted At: Sunday, August 06, 2006 7:25 PM

Posted To: rec.aviation.ifr

Conversation: Help understanding Aspen VOR/DME approach

Subject: Help understanding Aspen VOR/DME approach



. Don't rely exclusively

on the IFR chart. If you do, you'll be unprepared.



Going into FSM on Saturday, I overheard a Hawker also landing at FSM on
Razorback Approach:



Hawker: "Razorback, what's that river off our left wing?"



App: "Say again?"



Hawker: "Razorback, Hawker xyz, what's that river off our left wing
please?"



App: "ah, that's the Arkansas River"



Some other wag (not me I promise): "Yep, on my VFR chart too"



There's a case of relying on the enroutes and plates to tell you
everything you need to know...