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Throttle curve settings

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Old 11-30-2010, 03:48 PM
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gruntled
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Default Throttle curve settings

Has anyone experimented with running any throttle curve setting other than full expo - ie half expo or linear?

It seems like having a more linear throttle would be a good thing, but it seems like full expo is the default and what most are using, so I guess I need to understand why it is preferable to have more of the throttle range crammed into less travel of the stick.
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Old 11-30-2010, 06:51 PM
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Default RE: Throttle curve settings


ORIGINAL: gruntled

Has anyone experimented with running any throttle curve setting other than full expo - ie half expo or linear?

It seems like having a more linear throttle would be a good thing, but it seems like full expo is the default and what most are using, so I guess I need to understand why it is preferable to have more of the throttle range crammed into less travel of the stick.
I have never tried a linear throttle setting but I was warned that it could make taxing difficult due to a larger response from the engine then what we are used to with the full expo which kinda makes sense to me.
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Old 11-30-2010, 09:03 PM
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Default RE: Throttle curve settings

I've been flying my Eagle on Half-Expo since I got it......
Greg
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Old 11-30-2010, 09:18 PM
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Default RE: Throttle curve settings

half expo is perfect - linear = WAYtoo touchy close to idle, no good for taxi or steady approach speed
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Old 12-01-2010, 01:58 AM
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Default RE: Throttle curve settings

What does half expo look like when on your TX screen as in per % -+ what

Oh JR radio here
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Old 12-01-2010, 05:28 AM
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Default RE: Throttle curve settings

As I understand it the reason to run expo is to make the thrust range be more linear. In linear mode you need to have the stick over three quarters up to get half thrust. In full expo when the stick is at halfway, you get about half thrust. The reason is because of the thrust to RPM curve as shown in your manual (half RPM only gives one quarter thrust). Expo does not cram more throttle into less travel, it spreads the thrust curve out to make the effective throttle more linear.
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Old 12-01-2010, 07:05 AM
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Default RE: Throttle curve settings


ORIGINAL: Hot Rod Todd

As I understand it the reason to run expo is to make the thrust range be more linear. In linear mode you need to have the stick over three quarters up to get half thrust. In full expo when the stick is at halfway, you get about half thrust. The reason is because of the thrust to RPM curve as shown in your manual (half RPM only gives one quarter thrust). Expo does not cram more throttle into less travel, it spreads the thrust curve out to make the effective throttle more linear.
I took almost the opposite from the graph in the manual, but I am probably not interpreting it correctly. To me this says that full expo is cramming 46% of total thrust into the top 25% of stick travel.

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Old 12-01-2010, 11:57 AM
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Default RE: Throttle curve settings

Half, Full or Linear Expo. . .that is the question.

Factory default setting is Full Expo. . .
Linear is suggested (my suggestion) for heavy jets and Turbo Props where the sensitivity below 1/2 stick is less of an issue. . .
Half Expo is just that. . .1/2 of the full Expo setting but less than the Linear setting.

I fly Full Expo with most all my jets (currently 3) and like it. My good friend Andy Kane uses Full Expo but adjusts the throttle curve to his liking within the 12X programs.

The three throttle curves built into the I.C.S. (ECU) were developed as a result of many, many requests from customers.

So, if flying a BVM BobCat, you would not be happy with Linear. . .due to sensitivity and the airframe weight it is pushing. I suggest you experiment and arrive at your desired setting. Remember, once running you can menu up to the "Start Info Run Radio" screen, click on Run and change expo. You can do this all during the same flight (not while in flight !) but while running.

Last, ONLY change throttle curve in your Tx AFTER you train the Tx and ECU.

Have a great Holiday. . .
Eric

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Old 12-01-2010, 12:06 PM
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Default RE: Throttle curve settings

Thanks Eric. I am going to give half expo a try. Sounds like a good compromise.
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Old 12-01-2010, 12:27 PM
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Default RE: Throttle curve settings


ORIGINAL: gruntled


ORIGINAL: Hot Rod Todd

As I understand it the reason to run expo is to make the thrust range be more linear. In linear mode you need to have the stick over three quarters up to get half thrust. In full expo when the stick is at halfway, you get about half thrust. The reason is because of the thrust to RPM curve as shown in your manual (half RPM only gives one quarter thrust). Expo does not cram more throttle into less travel, it spreads the thrust curve out to make the effective throttle more linear.
I took almost the opposite from the graph in the manual, but I am probably not interpreting it correctly. To me this says that full expo is cramming 46% of total thrust into the top 25% of stick travel.

.

Hello gruntled
To clarify the chart, the top yellow part is the throttle stick position, so at 25% of the stick travel you will have 6% of the thrust at full expo, 16% at half expo and 25% at linear
Hope this helps
Regards
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Old 12-01-2010, 12:36 PM
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Default RE: Throttle curve settings

Thank you. That is how I interpreted it as well.
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