BAF LOC 23

Paul Tomblin wrote:

I'm trying to figure out the BAF ILS 23 localizer approach. The normal
LOC 23 approach has a MDA of 900, and the LOC 23/DME approach has a MDA of
700 feet. After the FAF, there is a step down fix at 2.7 DME with a
_1160_ before it. So does this mean that if you don't have DME, you can
descend to 900 immediately after the FAF, but if you do have DME you can
only descend to 1160 until 2.7 DME? Why is it safe to descend to 900 in
one case, but only 1160 in the other?

--
Paul Tomblin http://xcski.com/blogs/pt/
My family's values included "Always state your assumptions and your evidence",
"first find out what the problem is, then fix it", and "feed your horse before
yourself". But you don't see people legislating those... -- Zeebee

That procedure is screwed up.

(Paul Tomblin) wrote
I'm trying to figure out the BAF ILS 23 localizer approach. The normal
LOC 23 approach has a MDA of 900, and the LOC 23/DME approach has a MDA of
700 feet. After the FAF, there is a step down fix at 2.7 DME with a
_1160_ before it. So does this mean that if you don't have DME, you can
descend to 900 immediately after the FAF, but if you do have DME you can
only descend to 1160 until 2.7 DME? Why is it safe to descend to 900 in
one case, but only 1160 in the other?

Every time we've had this kind of confusion here about an approach, it
turned out to be a charting error. I'm betting this is too.

There's no way to make sense out of this - it's just wrong.

Michael

It may not be a charting error, but a discrepancy, duly noted by the mention :

"VGSI and descent gradient not coincident".

See the TERPS manual :

http://av-info.faa.gov/terps/Policies1/TIL99014att.PDF

Michael wrote:

Every time we've had this kind of confusion here about an approach, it
turned out to be a charting error. I'm betting this is too.

Picking at nits: an error in the procedure, not the folks who make the charts.



There's no way to make sense out of this - it's just wrong.

Exactly.



Michael

On Mon, 11 Oct 2004 16:27:23 +0000 (UTC), (G
Farris) wrote:

It may not be a charting error, but a discrepancy, duly noted by the mention :

"VGSI and descent gradient not coincident".

See the TERPS manual :

http://av-info.faa.gov/terps/Policies1/TIL99014att.PDF


VGSI?? Visual Glide Slope Indicator?? What would one of these be, a
VASI?

TCH?? Threshold Crossing Height??

Acronym finder didn't find them and it would really help understand
what the article is about if I understood the acronyms. This may be
our answer.

Thanks for the link and clarification if you can.

z

TCH means Threshold Crossing Height. I added it to
http://www.acronymsearch.com/
It's also in the AIM.

Jose

--
(for Email, make the obvious changes in my address)

On Mon, 11 Oct 2004 16:27:23 +0000 (UTC), (G
Farris) wrote:

It may not be a charting error, but a discrepancy, duly noted by the mention :

"VGSI and descent gradient not coincident".

See the TERPS manual :

http://av-info.faa.gov/terps/Policies1/TIL99014att.PDF


In reviewing the ILS-23 approach plate, I did not see the above
phrase. Where is it located?

Thanks.
z

On 12 Oct 2004 02:17:39 GMT, (Teacherjh)
wrote:

Threshold Crossing Height

Thanks.

That one I though I remembered correctly. VGSI however I'm still not
sure of.

z

Visual Glide Slope Indicator; generic term for PAPIs and VASIs. It's in
the AIM.

zatatime wrote:

On 12 Oct 2004 02:17:39 GMT, (Teacherjh)
wrote:

Threshold Crossing Height

Thanks.

That one I though I remembered correctly. VGSI however I'm still not
sure of.

z

If you have the NACO chart note at the top center that this is a USAF developed
procedure, not an FAA procedure.

No doubt it is all screwed up, but getting it fixed is another matter.

Paul Tomblin wrote:

I'm trying to figure out the BAF ILS 23 localizer approach. The normal
LOC 23 approach has a MDA of 900, and the LOC 23/DME approach has a MDA of
700 feet. After the FAF, there is a step down fix at 2.7 DME with a
_1160_ before it. So does this mean that if you don't have DME, you can
descend to 900 immediately after the FAF, but if you do have DME you can
only descend to 1160 until 2.7 DME? Why is it safe to descend to 900 in
one case, but only 1160 in the other?

--
Paul Tomblin http://xcski.com/blogs/pt/
My family's values included "Always state your assumptions and your evidence",
"first find out what the problem is, then fix it", and "feed your horse before
yourself". But you don't see people legislating those... -- Zeebee