I want my 7-pack

Jaybird180

Jaybird180

Final Approach
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Jaybird180
Instrument scan- why is it that we refer to a 6 instrument scan and put so much emphasis or learning it in training when the 7th is required to hold a course?

Why not a 7 scan?
 
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Because you can just keep rotating it until the needle centers again.
 
Follow the magenta-lit line. :)

Mine had only 6.... I had an HSI.
 
If you keep up the scan of the traditional 6, those are going to be the first indications you are getting off course.
 
Gucci Pilot said:
If you keep up the scan of the traditional 6, those are going to be the first indications you are getting off course.
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This. I think the 7th instrument scan should be the compass. Always check your DG to your compass.
 
Gucci Pilot said:
If you keep up the scan of the traditional 6, those are going to be the first indications you are getting off course.
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This. You don't fly your CDI. The needles tell you how well your selected heading you've established on your DG is working (an HSI makes this real easy). Otherwise you'll fixate and start "chasing the needle". Consequently, nav instruments, like engine instruments, only need to be incorporated occasionally into your scan.
 
Yep, my instrument instructor points out that even without the autopilot the heading bug on my DG (well it is an HSI) is a very handy thing. You fly the heading and check the CDI to see if you need to adjust where that thing is set.
 
There is a helluva lot more to look at than just the 6 pack. But its a nemonic that is easy to remember that everyone knows. But I for instance have three magenta lines I must monitor. Also, changing artisist on the iPad is no easy task and with a handful of peanuts, trying to change radio freqs is a beaitch.
 
tsts4 said:
This. You don't fly your CDI. The needles tell you how well your selected heading you've established on your DG is working (an HSI makes this real easy). Otherwise you'll fixate and start "chasing the needle". Consequently, nav instruments, like engine instruments, only need to be incorporated occasionally into your scan.
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Okay, this makes sense in theory. How well does it work in practice? I'm not IR but I have flown SP for a couple pilots on approaches.

Recently, I flew with a pilot and after noting that his CDI was 3/4 full scale and we were getting to the point of a massive visual correction, I asked him to remove the foggles so he could correct.

I suppose a missed approach would have been more instructive and in retrospect, I should have given that more consideration. However in the interest of safety, the only other option was to call, "My airplane" and I didn't want to do that.
 
I learned using the King School so the mantra is make small corrections sooner rather than large corrections later. So on an approach the needle has to be incorporated into your scan much more frequently than when in enroute (your proverbial 7-pack) so that you have timely feedback as to how well your selected heading is working on keeping you on course. Say you start an approach with the CDI centered, if it moves you need make a heading change to correct it ASAP. The idea is to come up with a heading on the DG that stops the needle from moving -- that is the stopper heading. Once you've figured that out, turn some more to center the needle and once it's centered return to the stopper heading. From there on out the goal being to make small 1-2 deg heading changes to stay on course. The CDI tells you how well your selected heading is working.

An HSI makes this easy because it's all visually displayed on a single instrument that already part of the primary instrument scan. The HSIs on Garmin EFIS's (and probably other brands too but I only have experience with the G1000 and G3X) do all of the work for you by displaying a course track indicator bug on the outer edge of the HSI. This is the computed WCA and as long as you maneuver to keep this bug over the CDI, the CID will stay centered--no thinking required.
 
Jaybird180 said:
Recently, I flew with a pilot and after noting that his CDI was 3/4 full scale and we were getting to the point of a massive visual correction, I asked him to remove the foggles so he could correct.
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I wouldn't call it a bust till full scale deflection. Should of let him recover under the hood for practice, unless you guys were about to die.
 
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OkieAviator said:
I wouldn't call it a bust till full scale deflection. Should of let him recover under the hood for practice, unless you guys were about to die.
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Yes, I know it wasn't a bust. There were other considerations that caused me to make the choice to terminate the practice approach, including the fact that we'd decided to call it a night and land back at home base with this one. I don't know if he logged it or not; I simply asked him how he felt about the approach and he didn't answer.
 
Jaybird180 said:
Okay, this makes sense in theory. How well does it work in practice?
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It works very well in practice. I'll set the heading bug where I think it needs to be to stay on course, and I don't deviate to either side of it(bug is 5 degrees wide on each side of center). If I'm requiring more, I reposition the bug.
 
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