(Giwi) wrote
I've heard that some pilots have the authority to descend to CAT
II minimums (RA100) on CAT I intstrument approaches. If this is
true, then how is the CAT I approach altered? Is the DH simply
lowered? Seems like this would result in steeper approach angles
to make it work out right. Alternately it seems possible that
the DH is lowered farther along the inbound course...but
wouldn't this make it more difficult to transition out of the
cockppit and land?

Yes, the decision height is simply lowered. There is no
difference in the glideslope angle and touchdown point in
any of the ILS approaches for the same runway.
Part 121 aircarriers have a somewhat different definition
for CAT I approaches than the standard 200-1/2 that most
pilots understand CAT I to mean. This is spelled-out in
the aircarrier's FAA OPSPECS and usually limits the CAT I
pilots to 250-3/4 unless specific training requirements are
meet. These training requirements include handflying an ILS
to what ammounts to CAT II minimums (100-1/4). This flying
an ILS to CAT II minimums inorder to achieve CAT I approval
may be the source of the original question.

Bob Moore
ATP B-727 B-707
PanAm (retired 1991)