Primary instruments for pitch, bank, power

RalphInCA

RalphInCA

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RalphInCA
I am having a tough time, for some strange reason, wrapping my mind around what instruments are primary, and which are secondary for pitch, bank and power for various flight conditions.

I know what the instruments do, and how they work, but I can't remember which are primary and which are secondary.

Anybody know of any useful memory aides, or tricks that might help me here?
 
Yes, please. I have the same problem.
 
Pure memorization is how I did it for the instrument written.
 
What I did was to take the information from the texts and make up a grid summarizing this info. Then memorized the grid.

SheppardAir has,something like this as part of their memory aid sheet. Unfortunately the link that would get me to that isn't working, else I would post. Perhaps a current user of their product can share.
 
OkieAviator said:
Pure memorization is how I did it for the instrument written.
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I recall I could reason my way through it, by asking "What instrument first tells me I need to do something?"

So, for a constant airspeed climb, the airspeed indicator is the first instrument that tells you you need to change pitch, and so is primary. The others - attitude and VSI support that and are secondary. If it was a constant rate climb, the VSI would become primary.

Or in straight flight, the Heading Indicator tells you first if you need to bank the plane to get back on heading, so it's primary for bank. Turn coordinator and Attitude Indicator support the turn back to heading and so are secondary.

I think. It's been a long time. But it worked for me without resorting to memorization through multiple written exams over the years.
 
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RalphInCA said:
I am having a tough time, for some strange reason, wrapping my mind around what instruments are primary, and which are secondary for pitch, bank and power for various flight conditions.

I know what the instruments do, and how they work, but I can't remember which are primary and which are secondary.

Anybody know of any useful memory aides, or tricks that might help me here?
Click to expand...

There is no need to memorize them.

The primary instruments are the ones that give you the numerical value that you're trying to hold constant.

Trying to do a constant-airspeed climb, the primary pitch instrument is the airspeed indicator.

Trying to do straight and level, primary for pitch is altimeter and primary for bank is heading indicator.

If you're trying to do a standard-rate turn, the primary bank instrument is the turn coordinator.

The exception is that during the transition from one attitude to another, usually the attitude indicator is primary.
 
dmspilot said:
There is no need to memorize them.

The primary instruments are the ones that give you the numerical value that you're trying to hold constant.

Trying to do a constant-airspeed climb, the primary pitch instrument is the airspeed indicator.

Trying to do straight and level, primary for pitch is altimeter and primary for bank is heading indicator.

If you're trying to do a standard-rate turn, the primary bank instrument is the turn coordinator.

The exception is that during the transition from one attitude to another, usually the attitude indicator is primary.
Click to expand...

I never cared to learn the primary and supporting instruments, but your explanation clarified it for me. Thanks.
 
The pedagogy in this area is uniformly TERRIBLE.

In a nutshell, you use "absolute" instruments (HI, altimeter, ASI) as primary when maintaining something. You use rate instruments (TC, VSI) when changing something at constant rate (turns, climbs, descents), and you use the AI when transitioning from one state to another.

That doesn't cover constant airspeed climbs and descents very well, but it gets most of the other stuff.
 
Sounds like a good shortcut for keeping it straight, until after the test. Then forget it. It's a exercise in nonsense if limited-to-no practical value.
 
dmspilot said:
There is no need to memorize them.

The primary instruments are the ones that give you the numerical value that you're trying to hold constant.

Trying to do a constant-airspeed climb, the primary pitch instrument is the airspeed indicator.

Trying to do straight and level, primary for pitch is altimeter and primary for bank is heading indicator.

If you're trying to do a standard-rate turn, the primary bank instrument is the turn coordinator.

The exception is that during the transition from one attitude to another, usually the attitude indicator is primary.
Click to expand...

Excellent
 
dmspilot said:
There is no need to memorize them.



The primary instruments are the ones that give you the numerical value that you're trying to hold constant.



Trying to do a constant-airspeed climb, the primary pitch instrument is the airspeed indicator.



Trying to do straight and level, primary for pitch is altimeter and primary for bank is heading indicator.



If you're trying to do a standard-rate turn, the primary bank instrument is the turn coordinator.



The exception is that during the transition from one attitude to another, usually the attitude indicator is primary.
Click to expand...


Great explanation, and it's exactly as I learned it and found it much easier than my initial "I'll just memorize this stuff for the test" approach.

The only addition I'd like to make is the "why" for the AI being primary during transition (again, based on how I was taught). As an example, during transition from level flight to a standard rate turn to the left... all you know (for bank) to start is that you want the little airplane in the AI to lean to the left. You don't know how much until you check the TC, but to start the turn you want the AI to give you the right initial indication (that you've started a turn to the left). Once the TC shows you're at standard rate, that becomes primary for bank since you've established the turn.

With the above explanation and the understanding that the AI is usually primary during transition (because it'll give you a big picture "have made the right inputs" check), that should pretty well cover the primary/backup instrument stuff you'll want/need to know for instrument flying.

In practice, do I consider which instrument is primary vs backup? Not really, but only because I'll scan all 6 in a few seconds and as long as they're all doing what I expect to see them doing, I'm not too concerned with the whole primary/secondary thing. But, in the few times I've managed to get spatially disoriented, it's been nice to know I have that knowledge to fall back on.
 
Many people have a hard time wrapping their mind around the FAA idiotic explanations for this. Learn them by rote for the written, and then get an instructor who understands the control-performance theory.
 
What confuses people seems to be the thought that "control/performance" and "primary/supporting" are two different methods for flying the airplane. They're not.

If you want to hold an altitude, how do you know whether or not you're there? You look at the altimeter, right? Do you look at something different in control/performance than you do in primary/supporting?

What about airspeed? Rate of climb or descent? Transition to or from a climb?

"Performance" instruments are "primary" for steady-state flight. "Control" instruments are "primary" for transitions. "Supporting" instruments are what you look at to make sure the "primary" instruments are working properly.
 
mjburian said:
As an example, during transition from level flight to a standard rate turn to the left... all you know (for bank) to start is that you want the little airplane in the AI to lean to the left. You don't know how much until you check the TC...
Click to expand...

You can approximate, going 100 kts is roughly a 15 degree bank (TAS/10+5).

Place the plane in the basic "attitude" using the AI, then cross check the others (TC for std rate, etc).
 
kevmor99 said:
You can approximate, going 100 kts is roughly a 15 degree bank (TAS/10+5).



Place the plane in the basic "attitude" using the AI, then cross check the others (TC for std rate, etc).
Click to expand...


Right. I could have worded that differently, but essentially I want to start a turn in the correct direction. I know it'll be shallow, but not sure exactly where standard rate is from the AI. So use the AI to get in the right ballpark and then the TC to refine (at which point the TC becomes primary).

My issue early in training with the AI as primary was that I imagined using it for an extended period of time. When, in reality, I'm only using it for a few seconds during the transition. And then moving to the more detailed instrument to fine-tune the attitude.
 
I'm gonna put my flame suit on for this post, but....

My totally unscientific impression as a pilot and sim instructor is that pilots who have a good grasp of control/performance have more precise control over the airplane during normal and abnormal operations, but pilots who have a good grasp of primary/supporting are better at identifying and resolving instrument and navigational malfunctions.

And as my Psych major daughter says, "Correlation does not equal causation," or something like that.:D
 
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MAKG1 said:
Have you done any instrument training yet?

It does have some value.
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Yes, I am IR. I find the associations a semi-silly exercise, of mild academic interest, perhaps when sitting on a soft couch with a cup of warm milk. But, in all seriousness, if it works for you, that's all that matters for your training.
 
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