# Chart Help

Yup, I have another question about altitudes…

From what altitude am I allowed to deviate from R144? To me as a newbie to charts, it seems like I am also never allowed to fly under 1700ft… So, can I fly lower and when can I get off R144? Help would be appreciated!
This chart is for LGSR (Santorini)

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1700 feet is your minimum until you see the runway environment, or until you reach your missed approach point (and you do not have the runway environment in sight) in which you follow the missed approach procedure.

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In the US we have something called a VDP, which is a visual descent point for non precision approaches (like gps(no lpv) or vor which tells us where we can descend once we have the runway environment in sight, in a continuous position to land… etc

Not sure if europe has something like that because im a us pilot, so… ill defer to someone else on that

Thanks a lot! Is that knowledge required, or can you read that info from the chart? Like an abbreviation or something that states that that rule is in place

For sure its required knowledge. You never want to bust minimums before you have the runway environment in sight (thats why its there, for purposes of obstacle clearance and safety)… MAPt means Missed Approach Point on the chart.

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Thanks! I am still new to altitudes and charts in general, so your help is greatly appreciated. This minimum rule applies to every procedure (also ILS) right? But with ILS the minimums are lower I imagine. Or aren’t there any for ILS because of autoland

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Yes because that type of approach provides vertical and lateral guidance, so glideslope and localizer respectively

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Ok thanks! I will keep an eye out for minimums from now on

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ILS mins can go down to 200-300 ft off the ground

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And in the US, GPS LPV approaches are in the process of formally becoming a precision approach (because it gives you a glidepath and localizer) as well which is cool.

Just to issue a slight improvement on what you’ve said:

CAT I ILS’s minimums are 200 feet AGL of where the aircraft is expected to cross this point. For example, 200 feet AGL might be 278 MSL (see: Heathrow 27L CAT I ILS approach) at minimums location. CAT I are the the most common approaches in commercial aircraft for fields equipped with an ILS - this is because ILS signal is very precise and can get you very close to the ground. It is also by far the easiest and simplest to fly in terms of crew resource management.

In cases of worsened visibility (incl. RVR), pilots may opt to fly CAT II or CAT III (A|B|C) approaches.

CAT II ILS approaches work exactly like CAT I ILS but the minimums are lower to allow pilots to fly closer to the runway before seeing it. The procedure for CAT II ILS are a tad different and require additional installation of physical equipment on the airport. As such, airports may have CAT I ILS capability, but not CAT II/III. These allow the pilots to fly 100 feet AGL before seeing the runway (compared to 200 with CAT I ILS approaches). These also require additional briefing by pilots.

CAT III ILS approaches (A&B, there are also C but I personally have never come across them) essentially allow the pilots to have no decision height at all (albeit for A subtypes it’s 50 feet AGL), but do require a certain RVR. These approaches require the use of AUTOLAND by the aircraft. For CAT III A approaches, pilots must see that the autoland is lining the aircraft correctly for landing (on the centerline, in the touchdown zone) at 50 feet AGL. B subtype allows for no decision height at all, and lower RVR than CAT III A. CAT III C have no RVR requirements (in other words you do not have to see anything whatsoever outside the window). All CAT III approaches are properly briefed and can be quite the workload for pilots. Airports also have to install additional equipment to support these approaches.

Hope this provides a further explanation on different categories of ILS approaches :)

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• the link is not to Eurocontrol but to VatSim
• Eurocontrol chats are free available, but not no-copyright

It’s Eurocontrol via Chartfox which uses Vatsim as login

Too much information in my opinion for a beginner at charts. Heck I’m almost a commercial pilot (with IR) irl and I don’t need to know about Cat 2 and Cat 3 ILS approaches until my job at the airlines tbh…

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Easy to overcomplicate things of course, not sure if my reply is necessary but here’s my interpretation…

Just remember the key to IFR (and flying in general really) is “Am I at a safe altitude?”. Since we cannot see the terrain, we refer to these charts + other publications for altitudes. No matter where you are, there is a minimum.

So theoretically, if you are not on R-144, you would have to abide by a different published altitude, which would be much higher. So I don’t see why you would want to “get off of” the published procedure - The chart is telling you to fly R-144 where you can descend to 1700’… Once you are visual, then you can “get off” to maneuover to the runway. I wouldn’t think much passed that.

If you want my full analysis of the chart let me know since it may be easy to misunderstand your question.

C :)

I hear ya, I don’t know anything worth a red cent about Cat II/III approaches and i’ve been flying IFR commercially for almost 2 years hahah.

I just wondered about getting off R144 because it leads to the VOR directly and I would need to get off of it to align with the runway

Ok great so once you get to 1700’ and you can see the runway - Then you can visually maneuover to the runway.

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I understand your confusion when it looks like the chart is telling you to land crooked! One thing to keep in mind: Every IFR flight begins and ends visually. Once you are visual for landing - get youself lined up because you’re free to go! :)

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