Holding patterns are a fundamental part of the instrument rating learning experience. In Guatemala you rarely actually have to fly one, but they are required sometimes, so you better know what you are doing. A holding pattern looks like a race track course requested by ATC to deal with delays, traffic separation etc. Planes are not helicopters they cant stop in the air, but have to keep flying. A holding pattern is the next best thing to hover in the air. There are other reasons for a holding pattern to exist, that I wont be mentioning here. This article is about how the holding pattern works, not why it exists.
Several pictures of been taken from the FAA regulation.
So as mentioned before, a holding pattern looks like a race track. You need an identifiable point, like a fix on the track. Turns are supposed to be flown at standard-turn rate so the 180° turn should last a minute. The straight lines of the horse track should take a minute in no-wind or straight-wind conditions. Fairly easy, right? I still found 5 ways to mess up the holding pattern. You learn from mistakes and how to do it right is written all over the place. I am learning from every time I did it wrong. Every single time, I thought I have done it all and their is no other way to mess up the holding pattern, but I am surprised every time. Watch out for future additions to this article….
- Making left turns
The standard holding pattern turns are to the right. Now to be clear, there are left turns and if they are depicted in the chart, you have to fly them. They are there for a reason such as obstruction avoidance, kind of important. The way I tried to remember was that the holing turns were the opposite direction of airport traffic patterns. Well this is kind of like a German saying that goes like “the right hand is where the thumb is on the left side”. So just in case you cant remember which way the normal traffic patterns go, think of which way would be easier to manage for a pilot, sitting in the left seat look outside making turns. The standard airport traffic pattern is made out of left turns, this way the pilot can look outside and keep the runway in sight while flying around the airport. When you fly a holding pattern, you will be under IFR and potentially flying under IMC. There is no need to look outside or keep a visual reference in sight.
There are speed limits ranging from 200 to 265 KIAS depending on altitude. In my plane I don’t have to worry about these speed limits. There are good reasons to reduce speed in a holding anyways. As the name suggests, you are kind of waiting for something else to happen. You can do this two different ways: fast – burning the lots of fuel and by the way one turn in the pattern will still take the exact same time! or slow – burning less fuel. you are not going anywhere so might as well safe that fuel. Another reason for flying slower is the bank angle. The faster you fly, the more bank angle you will need to make a standard-rate turn. The rule of thumb is that for any speed you will need 15% of your speed as a bank angle. Say you fly at 100 KIAS, then you will need 15° of bank for a standard-rate turn. 15° is nice and shallow. When flying 160 KIAS, you will need 24° of bank. Aggressive banks in IMC are not recommended, so flying slower will allow you to bank more gently and fly safer.
- From the fix outbound
You enter the holding at the fix. If you make a direct entry, you will start turning after overflying the fix. One time I flew over the fix and then started measuring one minute. If a fix is given and the no other exceptions stated, there is only one way to fly the pattern. The orange holding pattern is incorrect, the black one is correct. Basically once you are established in the pattern, you need to turn when crossing the fix.
- Time the holding so the outbound leg lasts 1 minute
As mentioned in the introduction, a normal pattern should take 4 minutes to complete. In this case the inbound and the outbound leg will actually equally long, 1 minute. The regulation states that the only timing that matters for the holding pattern is the inbound leg. Now you will need to take note of the outbound leg, to be able to adjust it to result the inbound leg to last 1 minute. An example will clarify the point. Say you fly a holding pattern towards the fix inbound at 100 kts on a 360° heading. The wind blows from the north (360°) at 25 kts. Over the fix you turn and then you start taking the time. With the headwind you are now flying 125 kts ground speed. In a minute you will cover just over 2 NM. Time to turn back towards the fix, and take the time. Well now you have a 25 kts headwind and you are flying at 75 kts ground speed, so you will probably fly for 1 minute and 40 seconds to cover the same distance. So adjust the outbound leg and you should be flying the inbound leg for a minute.
- Time the inbound leg 1 minute at 16,000 ft
After doing all of the above wrong, I was flying the pattern nicely and even got the inbound leg right close to a couple of seconds. Even my technique of instrument scanning got more fluent as I was flying through the patterns. My safety pilot distracted me on purpose (thanks M.R.!) and so I had to fly the pattern many times before I got to measure the outbound leg and the inbound leg to make my adjustments. At home I realized that once again, it wasn’t flown correctly. We were over a fix west of MGGT where the MEA is 16,000 ft. Above 14,000 ft you are supposed to fly the inbound leg for 1 1/2 minutes. oh well
Can there be anything else missing? I haven’t even talked about holding entry methods. I find them rather intuitive, but then again, I should get out there and actually fly them, so I can add to this article.
Have I missed something? Let me know!
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