Primary and Supporting INstruments

SixPapaCharlie

SixPapaCharlie

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I can logically think through all of this but much like airspace for PPL, lots of people have their own home made charts, graphs, and more straight forward approaches to keep it straight. Given the amount of overlap here I was going to make my own but thought I would check with the gallery first.

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FWIW. If black and white text draws you like a moth to the flame. Gleim is for you. Geeesh... I am doing very well but I should have gone with sporty's.
 

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It's much simpler than those charts and graphs make it out to be. For instance, in level flight (regardless of turning, accelerating, etc) primary for pitch is always the altimeter. Why? Because we're talking about LEVEL FLIGHT. How are you going to know if you're level? Check the altimeter. The other two pitch instruments (attitude indicator and VSI) are supporting, because they'll show you pitch info but not as precisely as the altimeter for level flight. (It's tougher to tell when the AI is *exactly* level and the VSI has some lag.)

Any time you're "transitioning" or "establishing" something, the AI is going to be primary DURING the transition. For instance, when establishing a level turn you'll use the altimeter as primary for pitch (because we're LEVEL) and the AI as primary for bank. You'll do that because you're not sure how much bank you need but this will at least show that you are starting the bank in the correct direction and approximately the correct amount. Once you ARE ESTABLISHED in the turn, primary for bank becomes the TC, because all turns are done at standard rate.

I spent hours poring over the chart trying to memorize this stuff. Then spent about 20 mins with my instructor and had an "Aha!" moment. Think about what you're trying to accomplish and decide which instruments will best tell you the information you need. That'll be your primary for that "plane of motion". The other instruments that provide information for that plane of motion will be your supporting instruments. After a few scenarios, it will start to become clearer and easier to remember vs. having to think through each instrument and what you're doing.
 
I'm studying for my written too. Here's the way I've made sense of this...

First the primary instruments. The primary instrument is the instrument that ISN'T changing for the activity performed. For pitch, if you aren't changing altitude, it's always the altimeter. For bank, if you aren't changing direction, it's the HI. For power, if you aren't changing airspeed, it's the ASI.

While you are transitioning into a bank or climb, use the AI for primary for bank and pitch respectively.

When you are established on whatever maneuver you're on, for primary, use the instrument that displays the most useful information..TC for bank (constant rate turn), ASI for pitch (constant airspeed climb), VSI for pitch (constant rate climb).

The supporting instruments don't seem to change much.

Of course in real life, everyone uses the control/performance technique anyway.
 
As a VFR pilot it is hard to think of the TC as being primary over the HI.
When I turn, I turn to a heading.

I get that we are now talking about timed turns versus turns to a heading but it is not intuitive to me to think that way yet.
 
SixPapaCharlie said:
As a VFR pilot it is hard to think of the TC as being primary over the HI.
When I turn, I turn to a heading.

I get that we are now talking about timed turns versus turns to a heading but it is not intuitive to me to think that way yet.
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The HI will tell you when to stop your turn. But it won't tell you whether you're in a constant rate turn, a steep turn or just a shallow bank (other than the speed at which the HI is spinning, but it'd be much more difficult to determine standard turn rate using that than just looking over at the TC).
 
SixPapaCharlie said:
As a VFR pilot it is hard to think of the TC as being primary over the HI.
When I turn, I turn to a heading.

I get that we are now talking about timed turns versus turns to a heading but it is not intuitive to me to think that way yet.
Click to expand...

The way I understand it is that ALL turns in IMC should be constant rate turns (or shallower), but I'm sure I will corrected shortly.
 
Steve Job said:
The way I understand it is that ALL turns in IMC should be constant rate turns (or shallower), but I'm sure I will corrected shortly.
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That's exactly right. Standard rate unless otherwise instructed (sometimes half standard rate).

Also, I was taught that all turns on an IFR flight plan (even in VMC) should be done at constant rate. I'm not 100% sure this is true, but I suppose the controllers don't know whether you're VMC or IMC, so it seems feasible that they'd always expect IFR traffic to make standard rate turns.
 
Steve Job said:
The way I understand it is that ALL turns in IMC should be constant rate turns (or shallower), but I'm sure I will corrected shortly.
Click to expand...

all turns when IFR (doesn't have to be IMC) should be standard rate or 1/2 standard rate (Jets) - small corrections for heading are a different topic entirely
 
Primary and Supporting instruments is a bunch of crap you need to memorize for the written, that's it. Every CFI I worked with and even the DPE that did my instrument exam agreed.

What is important:
Developing a scan through practice. Keep it sharp with regular practice.
Knowing what failures affect what instruments, and how they act when they fail.
Practice flying with certain instruments failed.
 
dell30rb said:
Primary and Supporting instruments is a bunch of crap you need to memorize for the written, that's it. Every CFI I worked with and even the DPE that did my instrument exam agreed.

What is important:
Developing a scan through practice. Keep it sharp with regular practice.
Knowing what failures affect what instruments, and how they act when they fail.
Practice flying with certain instruments failed.
Click to expand...

I figure that might be the case. I would really like to ace the written.
That seemed to have had a large impact on the DPE I like when I did the Private.

Plan is to complete the gleim course to get my signoff.
I have a copy of the Kings IFR course that I am going to go through after.
Then it is Sporty's study Buddy until consistently in the high 90s

It is a lot of studying but it worked for private and I learn well either by making mistakes or from repetition. I don't want to learn from mistakes in a plane :)
 
SixPapaCharlie said:
I figure that might be the case. I would really like to ace the written.
That seemed to have had a large impact on the DPE I like when I did the Private.

Plan is to complete the gleim course to get my signoff.
I have a copy of the Kings IFR course that I am going to go through after.
Then it is Sporty's study Buddy until consistently in the high 90s

It is a lot of studying but it worked for private and I learn well either by making mistakes or from repetition. I don't want to learn from mistakes in a plane :)
Click to expand...

You should do whatever makes you most comfortable going into the written, but I wouldn't be too quick discount something like Dauntless or Shepard Air to go the "memorize the answers for the written" route. Unless it has changed drastically in the past year, the knowledge for the written is pretty different than the knowledge you'll need to know for the checkride and will use in actual IFR flying. For me, it seemed to work well using Dauntless to prep for the written (in a week, basically) and then move on to learning the "real" stuff using the Instrument Flying Handbook, Sportys videos and my instructor.
 
Steve Job said:
Of course in real life, everyone uses the control/performance technique anyway.
Click to expand...

dell30rb said:
Primary and Supporting instruments is a bunch of crap you need to memorize for the written, that's it.
Click to expand...
The primary/supporting system gets a bad rap because people try to memorize answers to test questions instead of simply doing what comes naturally in order to measure the pilot's performance--look at the instrument that's keeping score, the "primary" one. The control/performance system is what I'd use to explain instrument flying to a confirmed non-pilot: "Attitude plus power equals performance". That ought to satisfy them, but won't help them much in flying a plane.

dell30rb said:
Practice flying with certain instruments failed.
Click to expand...
The control/performance system requires an attitude indicator. If it fails, you revert to the primary/supporting system, whether you admit it or not.

dtuuri
 
I tried Shepard, but I hate rote memorization, and that's what Shapard's all about. Now I'm using Dauntless (which I also used 15 years ago for my private), and I really like their explanations. I also am striving for a perfect score (alas - I missed one on my private), but I'm in no hurry, other than I want the rating sometime in 2015. I have accumulated 30+ hours of simulated IFR time over the years, plus about 3 hours of actual (which is incredibly different than simulated). The first time I was in actual, it felt like the hand of God was pushing my arm into a bank, even though I knew better by looking at the instruments. Something I never felt in simulated. Moral of this story: don't listen to God. :-)
 
Flying precisely by instruments (with an attitude indicator or not) is something that is only learned with practice. Its a motor skill that must be kept sharp with practice, or it decays away. The other things on the written are regulations or knowledge that can be learned from a book or in a classroom. For example, currency requirements.
 
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dtuuri said:
The control/performance system requires an attitude indicator. If it fails, you revert to the primary/supporting system, whether you admit it or not.

dtuuri
Click to expand...

A very valid point. I do have an emergency backup AI of sorts (synthetic vision on iPad derived from Garmin Pilot/GDL-39 3D). I'm just wondering which method is used more often by the pros. Primary/supporting certainly has the advantage as far as it being less reliant on the vacuum system, although losing the HI would still force you to use the "supporting" instruments.
 
Other than to pass the written, you can forget all that confusing primary/supporting stuff. The FAA allows you to use/explain either primary/supporting or control/performance on the practical tests for both the pilot and flight instructor instrument ratings. The only time I ever cover that is when prepping someone for the written, and I have to review it myself to be able to teach it -- and then promptly forget it again once the client passes the test.
 
Ron Levy said:
Other than to pass the written, you can forget all that confusing primary/supporting stuff. The FAA allows you to use/explain either primary/supporting or control/performance on the practical tests for both the pilot and flight instructor instrument ratings. The only time I ever cover that is when prepping someone for the written, and I have to review it myself to be able to teach it -- and then promptly forget it again once the client passes the test.
Click to expand...
I agree
 
Ron Levy said:
Other than to pass the written, you can forget all that confusing primary/supporting stuff.
Click to expand...

Much like NDB work, tail wheel flying, and any number of other things, I think primary/supporting is only confusing or difficult if the instructor tells the student it is.

It's amazing what you can teach somebody whose mind hasn't been closed by you or someone else.:yes:
 
Ron Levy said:
Other than to pass the written, you can forget all that confusing primary/supporting stuff. The FAA allows you to use/explain either primary/supporting or control/performance on the practical tests for both the pilot and flight instructor instrument ratings. The only time I ever cover that is when prepping someone for the written, and I have to review it myself to be able to teach it -- and then promptly forget it again once the client passes the test.
Click to expand...

Question for you Ron (and others).

At page 3-6 in “Rod Machado’s Instrument Pilot’s Handbook,” Rod Machado says:

The control and performance concept of instrument scanning is often used by pilots flying high performance airplanes (although it’s perfectly OK to use in smaller airplanes, too). This method involves thinking of airplane control as the result of attitude and power equaling performance. The method places a great deal of emphasis on the attitude indicator in selecting an appropriate attitude to achieve a given performance. The reason this method is more suited to higher performance airplanes is that these aircraft typically have more sophisticated attitude indicators that permit finer, more precise pitch and bank adjustments. (Given the PFDs in today’s sophisticated TAAs or technically advanced “GA” aircraft, you’ll easily find the same level of instrument sophistication.)
Click to expand...

His comment makes it seem that it might be better to scan a standard steam gauge airplane with the “primary/supporting” method.

Can you further comment on this topic?

Thanks!
 
I've only given a couple of thousand hours of instrument training, but my experience is that control and performance is much easier to explain, much easier for the trainee to learn and apply, results in much more precise performance, and has much greater training transfer value as the trainee moves up to higher performance planes. So even if I'm teaching in a 172, I'll stick with C&P.
 
Ron Levy said:
I've only given a couple of thousand hours of instrument training, but my experience is that control and performance is much easier to explain, much easier for the trainee to learn and apply, results in much more precise performance, and has much greater training transfer value as the trainee moves up to higher performance planes. So even if I'm teaching in a 172, I'll stick with C&P.
Click to expand...

Thank you.
 
register@teamandras.com said:
Question for you Ron (and others).

At page 3-6 in “Rod Machado’s Instrument Pilot’s Handbook,” Rod Machado says:



His comment makes it seem that it might be better to scan a standard steam gauge airplane with the “primary/supporting” method.

Can you further comment on this topic?

Thanks!
Click to expand...

Control/performance lends itself to faster airplanes better than primary/supporting for a couple of reasons...first, pitch changes affect rate of climb far more at higher speeds. Since 1 knot is very close to 100 ft/min, you can use the rule of 60 to see that at 120 knots, one degree of pitch change will result in about 200 ft/min change on the VSI. With a reasonably light touch on the controls, it's pretty easy to maintain altitude looking primarily at the altimeter.

On the other had, an airplane flying 420 knots TAS is going to see about 700 ft/min for one degree of pitch change, so using the AI as your primary pitch reference is going to make things a lot easier.

Second, at 120 knots, a standard-rate turn is about 17 degrees of bank IIRC, so a small bank angle will show up fairly quickly on the DG, allowing good use of primary/supporting instrument flying. At 420 knots, however, heading change is so slow at low bank angles that the DG doesn't move very fast until your bank angle is steeper than would be advisable to allow as an error, so again, the control/performance method is advantageous.

That doesn't mean that primary/supporting is "better" than control/performance for slower airplanes, just that it's a more viable option for slower airplanes than for faster ones.
 
Ron Levy said:
Other than to pass the written, you can forget all that confusing primary/supporting stuff. The FAA allows you to use/explain either primary/supporting or control/performance on the practical tests for both the pilot and flight instructor instrument ratings. The only time I ever cover that is when prepping someone for the written, and I have to review it myself to be able to teach it -- and then promptly forget it again once the client passes the test.
Click to expand...

That's disappointing.
These training materials cost money.

They could have used the ink to print something more beneficial. :(
 
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