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Guest cj_flys_wmu

How do you do types of procedure turns? ex:45*... (n/)

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Guest fwsov

Hmmm, I'll be damned if know how to do a 45* procedure turn but in a light aircraft, a standard rate turn is done by bank angle. Assuming you maintain the same speed throughout the turn, you take that IAS, divide it by 10 and add 7, this will give you degrees of bank to maintain and you should complete a 360degree turn in approx 60secs.For the heavy jets, I think the standard rate turn is a 25degree bank and a max airspeed of 220KIAS (or something like that, someone correct me if i'm wrong)Regards, Andrew

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Guest cj_flys_wmu

Well, The easiest way to explain how a procedure turn works is to show you using an approach plate. I am not sure if you have ever seen or read one of these before, but the main way one of these procedures is used is to systematicaly reverse your direction during an approach. In the real world, I would say based on my limited experience flying instruments in general aviation aircraft, 99.9% of the time if you fly during the day you are going to be in a radar enviroment and the controllers are going to give you vectors to the final approach course. That is, give you headings to fly. If you go into an airport late a night and the local radar is closed, you might have to do a "full approach" as it is called and use a procedure turn. Also, it would be pretty rare to see a transport category aircraft do one, like a 747, 767, etc.Now, if you look at the approach plate below, you can see that I have highlighted the procedure turn section. On these NACO (government plates) they really do not look like much. I believe that the Jeppeson plates dipict it better. Anyway, the chart is always orientated north, so it is easier to orientate yourself to the approach. Now, the only time that we would have to do this procedure is if we were coming in from the North. The reason being, you have to some how reverse direction to head north east. What is great about a procedure turn is that you could almost come in at any direction and still make the approach. Now, coming in from the north, lets say on a 180 degree heading I would fly directly to the Kalamazoo VOR, which is labled and right on top of the airport. As soon as I get a TO/FROM flip on my OBI I know that I have flown right over the top of the VOR and I can turn to the "outbound heading" of 230 and track that 230 radial from the VOR, so we are heading southwest now. Now, there has to be some way of knowing when to start the procedure turn and the way that we can tell this is by that LUCAS intersection off the AUSTIN NDB. I would have that NDB tuned in and as soon as it gets to 125 TO, I would know that I can start my procedure turn.Since we know we are over LUCAS and have clearly identified it, we know exactly where we are on the approach. On the chart it says to stay with in 10 NM when performing the procedure turn. The main reason for this is that there is a certin altitude that we are going to be at, in this case 2500 ft., and we don't want to smack into the side of some antenna or tower that we can't see when crusing along in the clouds by going beyond 10 NM.For a 172 or Piper Cherokee I was tought to start timing for two minutes. So at LUCAS intersection we will start the timer for 2 minutes and continue on the 230 outbound heading. After two minutes you can start the first turn of the procedure turn. You will notice that there is a little arrow barb indicating that you have to turn to the left. Make sure that you turn in the direction of the arrow thingy (very important :-)). It has the 185 number on it so turn to that heading. When you are wings level on 185, start the timer and time for one minute. (One thing I forgot to mention, for instrument flying every turn should be standard rate.) Now after that the minute is up, you will notice that the reciprical heading is 005 degrees. Start turning to the right at a standard rate to about 005 degrees. The wind might drift you a little bit but what you are really looking for is that 050 radial to track inbound to finish the approach. It is one of those feel things to get it right.Really, that was a very long winded answer to a relitivly easy procedure. There are quite a few websites that have free downloadable approach plates. Usually ILS approaches will never generaly use a procedure turn. Most VOR and NDB ones will. Take care,C.J. StarrPPL, Instrument Student

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Guest

You mean 45 degrees of bank (steep turn) or a compass heading change of 45 degrees?Ray

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