"I will now turn and intercept a 240 heading" - IFR student
"COURSE! COURSE! NOT A HEADING!" - Tizi
I've often heard IFR students confuse headings, tracks, and courses. Just recently on an IFR FaceBook page an IFR student asked what is the difference. Rather than confuse them together, I've encountered students using them interchangeably. That is obviously not appropriate, and clarity is required to perform a safe and precise navigation.
Let's start by defining them and then let's provide examples.
Tizi-Definitions
HEADING. This is where the nose of the airplane points. Under IFR, we will never (NEVER, thank goodness!) plan on navigating by headings.
TRACK. This is the actual path of the airplane over the ground. Under VFR, we calculate a heading in order to fly a specific track over the ground. If you have no idea what I'm talking about then read this, you need it.
COURSE. This is a specific, desired track required to navigate from point to point. When you draw a line on skyvector.com between two airports, you are plotting a course. Think of course as your "desired" path over the ground. In a perfect world, your track = your course to get to your destination. If there were no winds, then heading should match track and course as well.
Examples
HEADING - When ATC tells you to fly vectors: "N227TW, turn left heading 220, vectors for ILS 10" - When you execute procedure turns. As the example below shows, you turn left heading 247 and right 067 to execute the procedure turn.
COURSE - Courses are mapped to get you from point A to point B. This is the theoretical direction you need to navigate (over the ground) to get from point A to point B. Because these are "theoretical" (which under IFR are required, to be honest), the GPS navigators will often call them "desired track". Garmin will show you the letters DTK. A navigator that provides DTK will give you one for every leg of your flight plan based on ground track, position, winds, etc.
TRACK - The only case where you will probably see the verbiage "track" is on a GPS navigator, like a Garmin Touch Navigator (GTN). A GPS will always plot courses from point to point on your flight plan. - Garmin is famous for providing you tracks to fly when entering and establishing in a holding pattern. This is a great feature but per the AIM you should be using headings and courses (for VOR based holds).
Example of a Traditional Holding Pattern
Here is a beautiful missed approach holding pattern at the CAE VORTAC. I've flown this approach many times and I can assure you that with category A speeds, this will be a parallel entry. I would do the following:
Home the CAE VOR (the textual missed instruction says "direct CAE") and fly whatever COURSE that is.
When sequenced, tune the R-155 and fly that COURSE outbound for 1 min.
Turn right on a HEADING of 015 to intercept the VOR COURSE R-335 (40 deg intercept).
Fly the COURSE R-335 until sequencing the VOR.
Turn left on HEADING 155 (outbound leg depicted on the hold) for 1 minute after I'm wings level and sequenced the VOR (whichever occurs last).
Turn left and re-intercept a VOR COURSE of R-335. Per the AIM, you're supposed to continuously change your outbound heading to optimally re-intercept the inbound leg. This was when GPS technology was very limited.
ALTERNATIVE (welcome to the future)
Fly the track calculated by the GPS navigator. Garmin will literally tell you what COURSE (in the form of DESIRED TRACK) to fly. If you learn to fly the Default NAV page on a GTN (or GNS, etc.) then you will be able to fly anywhere under IFR with great precision
That's it. It's that easy. But anyone can follow a desired track. Understanding the theory behind this makes you a great pilot. Remember... avionics failures are a thing. So don't assume you will never need to know this...
Oh yeah, this is the default NAV page, below. My students learn to love it. Cause I love it. That's because.... ah never mind. I'll shut up now.
Clear as mud?
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