For attitude instrument flying,

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John777

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IFH mentions using half bar and full bar width for correcting altitude deviation of more than 100' or less than 100'

Does anyone know how one/half bar width is referenced on AI?

John.
 
It's just using the thickness of the horizon line "the bar" on the AI, rather that the degrees indicator, as a pitch reference. This is "one bar width" nose up. The wings sit in a position that is higher than the horizon line that is about the thickness of the line. Nothing more complicated than that.
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Seriously you need to enroll in an IR program or purchase the King's or Sporty's IR packages at the minimum. Trying to self teach this material with haphazard questions on the internet is not the way to go. If you are really a Sim pilot, just say so and we'll still answer your questions, but it would help put things in context as to your actual skill level and knowledge base. Help us help you.
 
tsts4 said:
Seriously you need to enroll in an IR program or purchase the King's or Sporty's IR packages at the minimum. Trying to self teach this material with haphazard questions on the internet is not the way to go. If you are really a Sim pilot, just say so and we'll still answer your questions, but it would help put things in context as to your actual skill level and knowledge base. Help us help you.
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Hopefully he's not trying to teach himself how to fly a real airplane. Good way to die early.
 
I'll try to take a pic of my attitude indicator... I could have easily asked this question since my AI doesn't look (at all) like the one in the book.

I'm guessing it's the standard mooney one, with the KFC 200(?) autopilot. Instead of a line, there's a dot, and then (to my aging eyes) a couple of orange chevrons that meet at a point in the middle. It's low contrast. Low, low contrast, and I've learned that level is (cover about half the ball), their "half a bar" is "cover almost all of the ball (up)" or "uncover the ball and a little bit of brown" (down). It's annoying as hell, because to me the orange chevrons appear to fade out as they approach the ball so I can't really tell a distinct point that covers the ball.
 
Mistake Not... said:
I'll try to take a pic of my attitude indicator... I could have easily asked this question since my AI doesn't look (at all) like the one in the book.

I'm guessing it's the standard mooney one, with the KFC 200(?) autopilot. Instead of a line, there's a dot, and then (to my aging eyes) a couple of orange chevrons that meet at a point in the middle. It's low contrast. Low, low contrast, and I've learned that level is (cover about half the ball), their "half a bar" is "cover almost all of the ball (up)" or "uncover the ball and a little bit of brown" (down). It's annoying as hell, because to me the orange chevrons appear to fade out as they approach the ball so I can't really tell a distinct point that covers the ball.
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I'd guess the OP has never seen any attitude indicator in real life.

It's quite odd that he doesn't answer questions about his background and intent. I'd be much more inclined to help out if he was forthcoming about that, even if it's "I'm working on a sim model" or "I'm prepping for a role in a film."
 
Ah.

Still, if I had infinite money, I'd love to replace this AI. I think it's made the flying part of the IFR training harder than it had to be at first. (Instructor: "Go to your AI, find an attitude, lock it up." Me: "My AI sucks, and I can't find a repeatable reference.")

On the bright side, partial panel is easy, since early on I learned to ignore the AI and compensate with what was left.
 
tsts4 said:
Seriously you need to enroll in an IR program or purchase the King's or Sporty's IR packages at the minimum. Trying to self teach this material with haphazard questions on the internet is not the way to go. If you are really a Sim pilot, just say so and we'll still answer your questions, but it would help put things in context as to your actual skill level and knowledge base. Help us help you.
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That.

Just buy the king program.
 
Mistake Not... said:
I'll try to take a pic of my attitude indicator... I could have easily asked this question since my AI doesn't look (at all) like the one in the book.

I'm guessing it's the standard mooney one, with the KFC 200(?) autopilot. Instead of a line, there's a dot, and then (to my aging eyes) a couple of orange chevrons that meet at a point in the middle. It's low contrast. Low, low contrast, and I've learned that level is (cover about half the ball), their "half a bar" is "cover almost all of the ball (up)" or "uncover the ball and a little bit of brown" (down). It's annoying as hell, because to me the orange chevrons appear to fade out as they approach the ball so I can't really tell a distinct point that covers the ball.
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I may have seen one of those long ago in an M20C but a photo would help. If there is a way of showing level, there should be some equivalent of "bar up bar down" measurement.
 
midlifeflyer said:
I may have seen one of those long ago in an M20C but a photo would help. If there is a way of showing level, there should be some equivalent of "bar up bar down" measurement.
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This is what's in my M20-C, doesn't look like what he's describing . . .
 

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Hank S said:
This is what's in my M20-C, doesn't look like what he's describing . . .
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What I pictured in my head based on what he was describing was some sort of flight director...

Obviously yours is not one.
 
Its kinda like this, only the little white triangle in the center is a single dot:
 

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Aha. I think this is it:
 

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Mistake Not... said:
Aha. I think this is it:
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Yea, I guess if you wanted a bar width on that one you'd have to use the side markings where the current attitude horizon line is offset from the 'background' one though it might be thinner than the other style bar.

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My mouse writing is pathetic!
 
exncsurfer said:
Yea, I guess if you wanted a bar width on that one you'd have to use the side markings where the current attitude horizon line is offset from the 'background' one though it might be thinner than the other style bar.

View attachment 49145

My mouse writing is pathetic!
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That will work in fast cruise, where the attitude is close to zero pitch. But it will not work in slow cruise. You'll have to read "bar widths" off the triangle. Not ideal.
 
Mistake Not... said:
Aha. I think this is it:
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Not harder. Just differenter ;) We're not talking exactitude here, just a way of visualizing small pitch changes on the AI.

@MAKG1 is right. It's possible but probably less useful for some to read the point of a flight director triangle as being 1/2 or 1 or 1.5 bar widths up or down.

But the use of "bar widths" is only one way of accomplishing the same small pitch change visualization task. You still have those nice lines giving degrees of pitch. One "bar width" (which might vary slightly from AI to AI anyway!) is something marginally less than 5°. So on an AI like this, think in terms of estimating 2-5° pitch changes rather than estimating bar measurements.

If you look at those nice approach configuration charts people make, you'll see some talk in terms of bar widths, some talk in terms of pitch degrees, and some don't even mention them at all, leaving it to the pilot to understand these are all very small (heck the biggest "normal" one is a Vy climb which is just about on the 10° line in many light singles). It's the same thing with the same goal. The differences reflect nothing but technique differences, sometime related to instrument differences but most pilot differences.
 
Mark, bar widths are much smaller than that. 1 deg on all the AIs I have access to.

Curiously, G1000 PFDs also have the triangle, even with the FD turned off. I can't say it's given me much trouble hand flying.
 
I always thought the bar-width thing was a weird thing to put in writing and to test on since AIs are so different, seems like an impossible task to standardize it.

If I'm doing a slight correction (1/2 bar width) I'm looking at the AI to pitch slightly and then cross-checking my Altimeter, ASI, and VSI. If I see my VSI bottoming out, I look back at my AI and correct.
 
labbadabba said:
I always thought the bar-width thing was a weird thing to put in writing and to test on since AIs are so different, seems like an impossible task to standardize it.
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I don't recall ever being tested on bar widths or even thinking of it as something to be tested on. I double-checked and the word "bar" doesn't appear in the Instrument ACS or the most recent previous PTS. Have you seen something in the knowledge test on it?
 
midlifeflyer said:
I don't recall ever being tested on bar widths or even thinking of it as something to be tested on. I double-checked and the word "bar" doesn't appear in the Instrument ACS or the most recent previous PTS. Have you seen something in the knowledge test on it?
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I believe so. I put the written off til the end, and I'm drilling for it now. Seems like I've seen questions about "how much would you pitch for 250'/min, 500ftmin, etc." Answers were in bar widths. I think it's mentioned that way in the Instrument Flying Handbook.

That's obviously not proof, but...
 
Mistake Not... said:
I believe so. I put the written off til the end, and I'm drilling for it now. Seems like I've seen questions about "how much would you pitch for 250'/min, 500ftmin, etc." Answers were in bar widths. I think it's mentioned that way in the Instrument Flying Handbook.

That's obviously not proof, but...
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We know the Handbook talks about it. But the handbook gives a lot of other tips and tricks that aren't tested too.

Besides, the handbook actually talks in terms of both:

Changing the “pitch attitude” of the miniature aircraft or fuselage dot by precise amounts in relation to the horizon makes pitch changes. These changes are measured in degrees, or fractions thereof, or bar widths depending upon the type of attitude reference. The amount of deviation from the desired performance determines the magnitude of the correction. (my emphasis)​

If you have a chance to check as you are drilling, great. And I would agree with you it's weird.
 
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midlifeflyer said:
We know the Handbook talks about it. But the handbook gives a lot of other tips and tricks that aren't tested too. If you have a chance to check as you are drilling, great. And I would agree with you it's weird.
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again, not proof it'll be on the written, but I did a question search in the dauntless android written test prep app for "bar width" and get questions like:

As a rule of thumb, altitude corrections of less than 100 feet should be corrected by using a: "half bar width on the attitude indicator".
 
Mistake Not... said:
again, not proof it'll be on the written, but I did a question search in the dauntless android written test prep app for "bar width" and get questions like:

As a rule of thumb, altitude corrections of less than 100 feet should be corrected by using a: "half bar width on the attitude indicator".
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A little weird, but so are a lot of knowledge test questions. And it is a good rule of thumb depending on the type of AI. I'd study it as an exercise in comparing bar widths with equivalents. The idea is still to have that picture of small corrections in your mind.
 
I took the IRA written twice (first one expired), as well as the CFII and IGI within the past 5 years, and don't recall any test questions mentioning bar widths.
 
dmspilot said:
I took the IRA written twice (first one expired), as well as the CFII and IGI within the past 5 years, and don't recall any test questions mentioning bar widths.
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I took the IRA on Monday of this week. No bar widths questions.
 
Mistake Not... said:
again, not proof it'll be on the written, but I did a question search in the dauntless android written test prep app for "bar width" and get questions like:

As a rule of thumb, altitude corrections of less than 100 feet should be corrected by using a: "half bar width on the attitude indicator".
Click to expand...

yep, they're absolutely in the question test bank. But we're also talking 2 or 3 out of a 1,000 questions so the chance of getting one on the test is low.
 
midlifeflyer said:
A little weird, but so are a lot of knowledge test questions. And it is a good rule of thumb depending on the type of AI. I'd study it as an exercise in comparing bar widths with equivalents. The idea is still to have that picture of small corrections in your mind.
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... as well as having a specific target for the pitch change rather than just pulling or pushing the yoke.

"Aim small, miss small" for those of you who have seen "The Patriot".
 
tsts4 said:
Seriously you need to enroll in an IR program or purchase the King's or Sporty's IR packages at the minimum. Trying to self teach this material with haphazard questions on the internet is not the way to go. If you are really a Sim pilot, just say so and we'll still answer your questions, but it would help put things in context as to your actual skill level and knowledge base. Help us help you.
Click to expand...
This is exactly the notion that I'm getting with many of his questions as well. We're happy to answer your questions, but many of them should be answered easily by some research on your own or from your CFI which should be the main database for answers.
 
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