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Old 17th June 2014 | 15:22
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: Military
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From: florida
Sounds like a trip thru memory lane, OG

I don't think the "direct" roll implementaion is an "acceleration" command of the control surfaces, but actual control surface position. The "rate" of movement seems to be dependent upon the "gains" that the FCS uses according to aircraft configuration. This was same for the primitive FBW law we had in the Viper - "x" dynamic pressure according to gear up or gear down.

The "direct" command of aileron position is vastly different than commanding a roll rate or whatever. So at stick being neutral, the ailerons should move to whatever position the "neutral" position of the stick is using according to last trim condition.

Our force on the Viper stick was pretty simple, and just relaxing on the stick with zero force resulted in the jet rolling according to the last trimmed roll rate ( usually zero). You can see this on the Thunderbird solo pilots that do rolls to inverted passing in front of the crowd. The sucker flat stops rolling and no overshoot.

Just my experience and observations, but the 'bus FCS seems to implement the Viper laws except for the max bank angle.
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