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Trimming out my 3.1 Super Extra

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Old 07-02-2018, 06:07 AM
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RickP
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Default Trimming out my 3.1 Super Extra

Hello all,
I am struggling on fine tuning trimming my aircraft. You would think after flying this for so long I would have it down, but I know it can be better and I find myself chasing my tail with this.

I know there must be some really good resources on this site or perhaps in publication that I can buy. What do you guys like and you point me to any really good references? Much Thanks,
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Old 07-10-2018, 04:16 PM
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Old 07-11-2018, 04:10 AM
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Great Resource, thank you!

I've been directed to the Peter Goldsmith articles as well. I remember those from a long time ago. Quick google search will lead you to him. Any other good sources? Are there any books out there you guys like?
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Old 07-12-2018, 08:53 PM
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Not really. Trimming has become somewhat a lost art. When you stop to think that there may be 500 guys combined that fly pattern and IMAC in the country. Most sport pilots are happy just to fly around and really have no idea why some airplanes fly better then others. How many times have you read someone's opinion that a particular airplane is prone to tip stalling? Do they ever stop to think that if they set it up poorly then it's going to fly poorly?
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Old 07-13-2018, 04:46 AM
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Thank you,
I started with CG and decided I need to start moving it more rearward. Immediately, I noticed the increase in pitch sensitivity. But curiously it did not really translate into any down trim required on the elevator. I really didn't like it at first, but I've gotten used to it and fooling with the expo may help. On the inverted 45 degree up line I still pull to the canopy pretty significantly. I'll fly it like this a while longer and take another stab at it. How far is too far though? I'd really like to get to the point where inverted feels very neutral...
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Last edited by RickP; 07-13-2018 at 04:47 AM. Reason: changed belly to canopy
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Old 07-13-2018, 07:58 AM
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Are you wanting to get to a good IMAC setup? If so what worked well for me was to move the CG so that from an inverted 45 it would take 7 seconds to arc to inverted level hands off. From there you can start adjusting the uplines and downlines. Most guys initially use way too much throw. 15 degrees up and 18 degrees down is all the elevator you should need. You will need a good dose of expo as well. If you are used to a sensitive setup this will feel odd to you but you will adjust to it.
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