To try and help, seems to be a little confusion between Min Decision Altitude and Min Decision Height. First of all an ILS is always landed manually after decision is made at MDA which is Baro pressure ALTITUDE on local QNH. ILS Cat II or Cat III (A,B or C) are Autoland modes with decision made at MDH from Radio Altimeter (Height above ground). Just to confuse the issue if an Autoland is to be carried out most carriers set the ILS MDA on the altimeter and the MDH on the Radio Altitude so if in the event of losing an A/P during approach the approach can be continued with the decision made at MDA, to land manually. Hope this clarifies a little.Cheers and Blue side up.

To try and help, seems to be a little confusion between Min Decision Altitude and Min Decision Height. First of all an ILS is always landed manually after decision is made at MDA which is Baro pressure ALTITUDE on local QNH. ILS Cat II or Cat III (A,B or C) are Autoland modes with decision made at MDH from Radio Altimeter (Height above ground). Just to confuse the issue if an Autoland is to be carried out most carriers set the ILS MDA on the altimeter and the MDH on the Radio Altitude so if in the event of losing an A/P during approach the approach can be continued with the decision made at MDA, to land manually. Hope this clarifies a little.Cheers and Blue side up.

Ok, thanks for this. So in the end, MDA and MDH is actually at the same point? For example EGKK 26L, MDH 100 equals MDA 296, correct?So when I'm landing with autoland (which is rare in my case), I should use the CAT II column on the chart. In this case, MDH 100 ft. And when doing ILS manually, I should use the ILS column on the chart, correct? in this case, MDA 400 ft (which equals MDH 200 ft). Btw, I thought that MDA also meant Minimum Descent Altitude?

To try and help, seems to be a little confusion between Min Decision Altitude and Min Decision Height. First of all an ILS is always landed manually after decision is made at MDA which is Baro pressure ALTITUDE on local QNH. ILS Cat II or Cat III (A,B or C) are Autoland modes with decision made at MDH from Radio Altimeter (Height above ground). Just to confuse the issue if an Autoland is to be carried out most carriers set the ILS MDA on the altimeter and the MDH on the Radio Altitude so if in the event of losing an A/P during approach the approach can be continued with the decision made at MDA, to land manually. Hope this clarifies a little.Cheers and Blue side up.

ILS have decision altitudes (heights), regardless of CAT1, 2, or 3. MDA(H) are for non-precision approaches. CAT1 is a precision approach.That EJKK chart isn't as user friendly as Jeppesen plates. The Jepps plates tell you RA for Radar Alt minimums if the approach is based on that or DA(H) if it's BARO.For CAT2, I guess I'd use the 72RA for the CATII CAT C approach.

Hey,please just to clear it up, the app minimums will be only at ILS app? if no, how can i know it for a visual app, and btw i checked the BNN arrival for london heathrow 27L and there was no plate that tells the decide altitude is that appears only at ILS charts? thanks again

Decision Altitude is for ILS cat 1. It is based on MSL, or referred to as BARO.Decision Height is AGSL, so you use the radio altimeter to determine that. CAT IIs will generally be 100. May be heigher, but certainly not lower. CAT IIIs can go down to DH 0.For a visual, you fly as low as you are cleared to. Fly using the visual cues, and when you see the runway, enter the pattern, and land.For non-precision (non glideslope), you got MDA. Treat it the same as a DA or a DH. Fly the approach, and when you hit the MDA, and you don't see the runway, go-around, no questions asked.Visual approaches do not have minimums. Other than of course you are in VFR conditions. I have seen plates with altitudes on them, but they are recommendations for certain way points. Don't recall seeing a visual plate with minimums like those found on ILS or non-precisions approaches.

Decision Altitude is for ILS cat 1. It is based on MSL, or referred to as BARO.Decision Height is AGSL, so you use the radio altimeter to determine that. CAT IIs will generally be 100. May be heigher, but certainly not lower. CAT IIIs can go down to DH 0.For a visual, you fly as low as you are cleared to. Fly using the visual cues, and when you see the runway, enter the pattern, and land.For non-precision (non glideslope), you got MDA. Treat it the same as a DA or a DH. Fly the approach, and when you hit the MDA, and you don't see the runway, go-around, no questions asked.Visual approaches do not have minimums. Other than of course you are in VFR conditions. I have seen plates with altitudes on them, but they are recommendations for certain way points. Don't recall seeing a visual plate with minimums like those found on ILS or non-precisions approaches.

thanks man, great!(:, one final question, how can i determinate either if its a cat1 or catII? and if its wrote in the charts on catII 255, is it BARO or radio i mean i need to set it to 255 baro or RADIO? thanks again!(:

It should say at the top of the Chart. If it just says ILS, bet that it is a CAT I. FAA charts for example say ILS (CAT II) on the title.Some charts have the different minimums for different CATS listed together.Most minimums for a CAT I will be written as such DA (DH) and DH is usually written in a smaller font , such as 400 (200). That would mean set your BARO minimums to 400, and that will coincide when your radio altimeter (what your GPWS calls go by) at 200.CAT IIs will list it the other way. It will read for example RA 101 100 DA 764. So set your radio altimeter to 101, for a decision height of 100, which corresponds to 764 on your baro altimeter. You see this type of writting, it is a CAT II.CAT IIIs will not have an RA, but will list minimums as RVR, which corresponds to how far forward you can see down the runway. You compare this information from your weather brief to determine which degree of CAT III to fly. If you are flying in no vis what so ever, you shoot a CAT IIIC, which is of such precision, you never need to see the runway at any point prior to landing.

It should say at the top of the Chart. If it just says ILS, bet that it is a CAT I. FAA charts for example say ILS (CAT II) on the title.Some charts have the different minimums for different CATS listed together.Most minimums for a CAT I will be written as such DA (DH) and DH is usually written in a smaller font , such as 400 (200). That would mean set your BARO minimums to 400, and that will coincide when your radio altimeter (what your GPWS calls go by) at 200.CAT IIs will list it the other way. It will read for example RA 101 100 DA 764. So set your radio altimeter to 101, for a decision height of 100, which corresponds to 764 on your baro altimeter. You see this type of writting, it is a CAT II.CAT IIIs will not have an RA, but will list minimums as RVR, which corresponds to how far forward you can see down the runway. You compare this information from your weather brief to determine which degree of CAT III to fly. If you are flying in no vis what so ever, you shoot a CAT IIIC, which is of such precision, you never need to see the runway at any point prior to landing.

thank you very much, i didn't really understand what's the difference between catII and catI and cat III I will look at google for it as for the RA i looked at my charts, and couldn't see any RA DH or something, i am using the gatwick 26L ILS approach charts, but thanks any way!(: BTW in the charts there is something like plate with CATII AND CATI and the numbers for class A, B, C ,D .

Class is for the specific plane. In short, 737 is class C.It may be that the chart you are using assumes you know which type it is, and thus does not label the minimums in the manner I mentioned. Can you post a link or a pic of the chart you are looking at, that way there is some common ground in the discussion?

chrome://print/ here it is, thanks again(:here, it isoh, i cant put, it up, i will work on it when i will back from school, sorry

On a related matter, Is there a fast way to change the baro minimums value? Setting it when flying into DEN for example (to 54xx ft), takes quite a lot of knob twiddling.* Orest

I am afraid there is some confusion and some misconceptions present.First, let's take a look at approach categories.All Boeing 737-600 and 700 planes will fall into category C.Most 800s will be D. Some 800 that have lowered MTOW and MLW will fall into category C. Thisis done by some airlines like Ryanair for the reason of lower landing fees. Most if not all 900s will be D.Approaches:Non precision approaches use MDA. It is not quite the same as DA(H) in precision approaches, as you don't need to immediately go around if you don't see the runway elements (incl. approach lights) when you reach it, instead, you might continue to Mapt, where you need to go around.ILS CAT I uses Decision Altitude. This should be set using BARO minimums, as RA guidance is not guaranteed.ILS CAT II and III use RA, and minimums (DH) should be set using RADIO setting. Those do not need to be AUTOLAND, almost always in CAT II and in some cases in CAT IIIa (for example, when using HUGS).

How many times within NGX and FSX have you experienced a go around cause of minimums requirements not met ?

I am afraid there is some confusion and some misconceptions present.First, let's take a look at approach categories.All Boeing 737-600 and 700 planes will fall into category C.Most 800s will be D. Some 800 that have lowered MTOW and MLW will fall into category C. Thisis done by some airlines like Ryanair for the reason of lower landing fees. Most if not all 900s will be D.Approaches:Non precision approaches use MDA. It is not quite the same as DA(H) in precision approaches, as you don't need to immediately go around if you don't see the runway elements (incl. approach lights) when you reach it, instead, you might continue to Mapt, where you need to go around.ILS CAT I uses Decision Altitude. This should be set using BARO minimums, as RA guidance is not guaranteed.ILS CAT II and III use RA, and minimums (DH) should be set using RADIO setting. Those do not need to be AUTOLAND, almost always in CAT II and in some cases in CAT IIIa (for example, when using HUGS).

Hey, thanks for the info, i am still not sure whether to choose catII or catII or catIII, whats the difference and how i can tell whether to do catII or catI? I took the charts for gatwick ILS 26L from here: http://www.californiaair.co.uk/Routes/UK/LondonGatwickEGKK/IACS/ILS26L.pdf

Hi. I wanted to specify, but then the browser crashed on me (twice) and I had to hurry to finish that post before having to leave to catch my bus.You may notice, that most everywhere there is a CAT II or III approach available, there will also be a CAT I ILS approach published. That is, because of when Low Visibility Procedures are used, there are constraints on some things, like usage of holding points, clearance areas and so. You might have noticed that CAT II or CATIII holding points are marked further away. These and other limitations mean, that when LVP ops are in place, the capacity of the runway is lower. Therefore CAT I approaches are generally used, when weather allows. With that, you need higher minima even on II/III equipped runways, so you can for ex. recognize if ILS signal is corrupted by, say, departing aircraft, or aircraft on a holding point too close to the centerline.