Turn COORDINATOR

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3WE
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Turn COORDINATOR

Postby 3WE » Mon Nov 11, 2024 8:10 pm

Jargon : Turn and Bank indicator = a needle and ball. Turn coordinator = an airplane-looking bar with a slightly off-level gyro that causes it to respond to roll AND turn.

Gabriel background check: Analog/Mechanical systems are perfectly capable of providing pure turn and bank indication's, and I thought the turn coordinator (which mixes a shred of bank into the turn indicator) was supposedly a superior instrument.

I spent a few hours wearing a hood (and doing MSFS) and found I could get by decently without the attitude indicator. (No experience with a turn and bank indicator.)

But, getting to the bottom line, why wouldn’t we make the pure electronic doodad a turn coordinator?

Why take it back to the old instrument?

Confession: I lost the link.
Commercial Pilot, Vandelay Industries, Inc., Plant Nutrient Division.

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Gabriel
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Re: Turn COORDINATOR

Postby Gabriel » Tue Nov 12, 2024 7:15 pm

All of the above I agree, with the clarification that the turn coordinator mixes yaw and bank RATES. I think that's what you meant, but just n case.
The intention is that in an established turn (fixed bank angle) it would indicate the same than the turn and slip indicator (a alternative but more accurate term for the turn and bank indicator), but when trying to keep the wings level it will provide an earlier cue of bank/roll onset (before the yaw rate starts to be detectable)

Now, here is where you lost me:
But, getting to the bottom line, why wouldn’t we make the pure electronic doodad a turn coordinator?

Why take it back to the old instrument?

Confession: I lost the link.
I don't know what you are talking about.

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3WE
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Re: Turn COORDINATOR

Postby 3WE » Tue Nov 12, 2024 10:32 pm

I found the link.

https://fb.watch/vPA8-sFTDE/?

It’s a cool demonstration, but (repeating) I thought the turn coordinator (which is a matter of a tilted vs horizontal gyro) was the superior instrument AND no reason it can’t be done electronically.

For Gabriel: I am logically EXTRAPOLATING: Why is the HOT NEW DIGITAL instrument not “equivalent” the OLD MECHANICAL instrument which [supposedly] provided better information? Why are we reverting to the old turn & bank needle?
Commercial Pilot, Vandelay Industries, Inc., Plant Nutrient Division.

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Gabriel
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Re: Turn COORDINATOR

Postby Gabriel » Tue Nov 12, 2024 10:44 pm

It’s a cool demonstration, but (repeating) I thought the turn coordinator (which is a matter of a tilted vs horizontal gyro) was the superior instrument AND no reason it can’t be done electronically.
Well, that depends. If you already have an electronic ADI and your backup for that is another electronic artificial horizon with its own backup power, I would like an instrument that gives me only the pure turn rate (yaw rate). If I am going to use it as backup in case of partial panel, yes I prefer the turn coordinator.
For Gabriel: I am logically EXTRAPOLATING: Why is the HOT NEW DIGITAL instrument not “equivalent” the OLD MECHANICAL instrument which [supposedly] provided better information? Why are we reverting to the old turn & bank needle?
I understand that you have not read the caption at the bottom of the video.

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3WE
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Re: Turn COORDINATOR

Postby 3WE » Thu Nov 14, 2024 1:08 pm

1. ***I understand that you have not read the caption at the bottom of the video.***
What makes you think we get the same things from links. There is no caption at the bottom of my video- and I didn’t see meaningful information above it, nor in the comments. Please copy/paste/screen grab at your convenience.

And how much instrument time do you have?

The turn coordinator provides perfectly useful turn rate information IN SPITE OF THE “ERROR” OF ROLL SENSITIVITY.

I guess “real” airplanes without crappy, vacuum-powered instruments don’t really need the BACKUP of the “improved” instrument…

Conversely, if you have solid-state “gyros”, I’d think you’d STILL MATHEMATICALLY depict the roll-sensitive aeroplanie on the instrument. Ironingly, it “banks” the opposite of the artificial horizon.
Commercial Pilot, Vandelay Industries, Inc., Plant Nutrient Division.

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Gabriel
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Re: Turn COORDINATOR

Postby Gabriel » Thu Nov 14, 2024 6:49 pm

1. ***I understand that you have not read the caption at the bottom of the video.***
What makes you think we get the same things from links.
I think your link points directly to that post with that video. It did for me every time I clicked on it (and it was several times in different days)
There is no caption at the bottom of my video- and I didn’t see meaningful information above it, nor in the comments. Please copy/paste/screen grab at your convenience.
Interesting. Aren't you seeing this video?
TC.png
TC.png (1.21 MiB) Viewed 449 times
And how much instrument time do you have?
Enough to be dangerous.
The turn coordinator provides perfectly useful turn rate information IN SPITE OF THE “ERROR” OF ROLL SENSITIVITY.
It does as long as you keep the bank steady. Flying in turbulence it adds extra noise since the airplane indicator will fluctuate in response to fluctuations in both roll and yaw, which is actually good if you are using it to control roll because you are partial panel and that's your backup. But if you have a battery back-ed-up electric or solid state AI, I'd prefer a turns and slip indicator that shows pure yaw isolated from roll.
I guess “real” airplanes without crappy, vacuum-powered instruments don’t really need the BACKUP of the “improved” instrument…
I agree, I was wondering what is the niche for this instrument. If I have a traditional six pack and I am going to spend the money in ONE instrument, I would buy either an electric gyro AI or a solid state one, with back-up battery of course.
Conversely, if you have solid-state “gyros”, I’d think you’d STILL MATHEMATICALLY depict the roll-sensitive aeroplanie on the instrument. Ironingly, it “banks” the opposite of the artificial horizon.
About any modern (even entry level) solid state PFD/HSI suit has a slip indicator built in the top triangle of the ADI and a yaw rate indicator (represented as a heading trend arc) in the digital compass.

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Gabriel
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Re: Turn COORDINATOR

Postby Gabriel » Thu Nov 14, 2024 7:05 pm

Here in the AD you can see that a little left rudder is needed (the bar under the top triangle is displaced a little bit to the left, stomp on the bar).
And in the HSI you can see the heading trend, which is indicating that, at the present rate you will be almost 20 degrees to the left in I don't know how many seconds. If it's 6 seconds, 18 degrees (still almost 20) would be 180 degrees per minute or a standard 2-minutes turn.
Garmin.png
Garmin.png (2.71 MiB) Viewed 448 times
Neither of these indications strikes me as intuitive, but I have never used this type of modern instrument. When my vacuum-powered artificial horizon was no out of service, I was happy.

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3WE
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Re: Turn COORDINATOR

Postby 3WE » Fri Nov 15, 2024 7:55 pm

Thanks for the screen grab. Cool that you can flip a “switch” to get different depictions…as long as the computer isn’t “thinking too much” so the pilots ask, “What’s it doing now?”
Commercial Pilot, Vandelay Industries, Inc., Plant Nutrient Division.


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