Originally Posted by
galaxy flyer
Rickair7777
I'm talking about real CANPA, not a "that looks bout right" guess what angle goes from the FAF to the MAP. There ISN'T an angle printed on the KSMX chart to any LOC-based chart. It is not possible for an FMS to calculate a Baro-VNAV glide path on a LOC approach. You can't mix FMS approaches and LOC ones.
Exactly, what vertical guidance is displayed in your cockpit, sir?
Denver
Circling, under Cat D, provides 550' HAA and 300' obstacle clearance MINIMUM, might be more depending on airfield.
GF
I was referring to the SMX BC approach and I am in a Cat C aircraft. So CAT C mins show 839' HAA. So to calculate a 3 degree slope out from the TDZ would be approximately 2.4 nm final for runway 30. The circling limitation for Cat C is 1.7nm. So for a night circle in low visibility and to assure yourself of 300 feet of obstruction clearance AND staying w/n circling radii until capturing the VASI on final you would be almost as high just doing a strait in and following the profile. What I was trying to say is that you could descend early on base but you had better know where all the rock piles with your name on them are.
This is why I do not perform circling approaches at night to unfamiliar airports. With that said even doing a strait in on a dark night and not being familiar with the area and trying to be stabilized 3.0 degrees would lead to a similar scenario with a geared piston engine aircraft. Kind of a catch 22 if you have never been there before. Now in an airplane that you can perform a steeper descent in and still be stabilized it is a non issue.