Peter R. wrote:
On 2/28/2007 10:38:03 AM, "Gordy" wrote:


FAA-H-8261-1
page 5-18

DA is currently used on RNAV approach charts with vertical descent guidance.
DA will replace DH for Category I precision IAPs. MDA and DA are referenced
to MSL and measured with a barometric altimeter. CAT II and III approach DHs
are referenced to AGL and measured with a radio altimeter.


Hmmm, I just looked at the online Instrument Procedures Handbook at page 5-18
and don't see that quote the

http://www.faa.gov/library/manuals/a...ures_handbook/

I even searched the entire chapter for a string from your quote and didn't
run across it. What am I missing? Are you quoting from a paper copy? If so,
is it one to a few years older?



It is the

MINIMUM DESCENT ALTITUDE,DECISION ALTITUDE,AND DECISION HEIGHTDAis
currently used on RNAV approach chart swith vertical descent guidance.
DAwill replace DHfor Category I precision IAPs. MDAand DA are referenced
to MSL and measured with a barometric altimeter. CATII and III approach
DHs are referenced to AGL and measured with a radio altimeter.

And, it is just plain wrong as to CAT III. It is misleading as to CAT
II because CAT II DA/DH is expressed in both MSL (Da/DA) and AGL for RA
(at RA site).