Approach Plates Questions

[Guest]

I was looking at the approach plate for KCLE ILS RWY 24L and I have questions about the descent minimums. This is what I see on the chart:Catagory A B C DWhat does this refer to? I am flying the PSS A320, B747, B777 what catagory would these planes fall into?S-ILS 24L 1046/32 260(300-5/8)S-LOC 24L 1140/50 354(400-1)What do these numbers mean?If I am asking newbie questions then by all means point me to an FAQ. By the way, I read Rod Machado's Ground School lesson that came with FS 2002 but the chart he refers to looks different than the current ones I am seeing.The chart also mention sidestep and circling but I don't feel like writing those numbers because they are broken up into catagories and such. I am such a slacker!

[Guest groundpounder75]

I may be able to help you a little.Category A B C D E refers to aircraft approach categrories..Cat A - Speed 90 knots or lessCat B - 91 to 120 knotsCat C - 121 to 140 knotsCat D - 141 to 165 knotsCat E - 166 knots or greaterThese are used to see what the minimum descent altitude would be based on the speed the your plane will fly the approach at. S-ILS 24L 1046/32....... 1046' MSL is the MDA for this approach. Not sure what /32 is. Also, 300-5/8 would be the minimum in-flight visibility required to complete the approach. So 300' to 5/8 of a mile would be the required visibility. I know there is a lot more to this but I thought I would tell you what I can think of right now.

[Guest]

the catagories are right on...32 is 3200 used with respect to the RVR if the visibility isn't reported, or the RVR is the prefered method of determining visibility. one technical note though, ILS (and i do believe all precision approaches use the term DH or Descision Height... MDA is used for non-precision approaches and is the minimum descent altitude since there is no vertical guidancepp-asel-ia

[Guest paulri]

Category answer in another post is correct.S-ILS-- Straight in ILS Approach1046--Decision Height (DH) MSL--missed approach if runway not in sight32--RVR in 100s of feet260--height of DH above touchdown zone (HAT)(300-5/8)--- Ceiling in feet (AGL) and Prevailing visibility in statute miles. S-LOC--a straight in Localizer only approach procedure (non-precision approach)--aircraft is not equipped with a GS receiver OR the GS on the ILS is inop.1140 Minimum Decent Altitude (MDA) MSL50--RVR354--HAT for the MDA(400-1)--same as above24L--the runway numberSide step is where you make an approach to one runway--in this case 24L, then sidestep for landing on the parallel runway (24R) when you have the runway in sight.Circle to land means you make your approach, in this case to 24L, then when you have the field in sight, circle to land on some other runway. For example, on runway 6 due to winds. For a circling approach, the number in the position of 354 in the example would be would be Height Above Airport (HAA) Paul

[Guest Akflyin]

The Catagories are also there to reference airspeed based on Gross weight of your aircraft. So if your Computed Gross weight for your aircraft type computes to an approach speed of say 190 kts then you look to see what category 190 kias falls under ( say C) then you would fly the Category C approach.Dave

[Guest Martin]

CAT I ILS approaches use DA (Decision Altitude), an altitude in feet MSL.DH is a height AGL and is used for CAT II and III ILS approaches.Martin767 fetishistIt's a lot like life and that's what's appealing

[Guest paulri]

That depends on which reference source you are using and who the proponent is of that information. In the US, if you look at the approach plates published by the Dept of Transportation and FAA (US Terminal Procedures), the information in the front of the books show DH (Decision Height) as an MSL number used for ALL approaches. The information area does not differentiate between type of ILS Approach, nor does the altitude presentations on those plates. However, in the DOD FLIP set of publications (General Planning--Terms page 2-15, Note 1 to be exact), DH is somewhat as you describe for ICAO purposes (although Cat II and Cat III are not mentioned).Confusing, isn't it!!! :-) Since the specific numbers under discussion are obviously MSL as published on the plates I use, I really do not care what they are called, just as long as I know what they mean and how to use them. Which I do. :-)Paul

[Guest]

So let me get this straight, If I am performing an ILS approach in the PSS A320 I would enter 260 for the decision height into the FMC?