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Building and Flying Related Boards › miniMax, Hi-Max, and AirBike General Discussions
Aileron Differential
7 posts
MickvdsJanuary 2, 2019, 12:22pm
Hello everyone

My partner in our build is doing some modelling on the ailerons and asked what the differential between up travel and down travel is for the Himax. I looked at our Construction Manual and it states equal travel up and down for the ailerons which seemed a bit strange to him.

I did a search of the site and found a discussion back in March 2017 where it was mentioned that 'The builders manual specifies minimums of 22 degrees up and 16 down on aileron travel' but like I said my Construction Manual only mentions equal travel.

Are there different manuals for different models ( at least the aileron section anyway)?

Are the values above true for the Himax?

Cheers, Mick
radfordcJanuary 2, 2019, 7:48pm
The reason for differential aileron is to minimize adverse yaw.  The rudder also is used to counter adverse yaw.  Most ultralights have very effective rudders and the ailerons are less so.  I would bet that you will find that having differential aileron on a Minimax isn't very noticeable or effective in flight and that you will still use the rudder predominantly.  
MickvdsJanuary 4, 2019, 5:33am
Thanks radfordc. I'm looking forward to getting her into the air and seeing how she handles
lake_harleyJanuary 4, 2019, 1:12pm
I haven't pulled out my plans or builder's manual, but when I completed my MiniMAX several years ago I measured aileron deflection. I don't remember the exact degrees by memory, but it did have more "up" aileron than "down" aileron travel. By the design/geometry of the aileron horn at the control stick, aileron differential is designed in. If you'd like details, or want me to double check my plans or look for notes for details of what I found on my plane, to back up what I'm saying, I'd be happy to do that.

Happy building.

Lynn
MickvdsJanuary 4, 2019, 1:38pm
G'day Lynn

If it's easy enough for you to have a look that would be great. Like I said it's for my building partner who is doing some mucking around with aileron balance.

I did some quick measurements on the cable installed already and found that full stick deflection either way gives about 6-8 mm less down travel of the cable as compared to the up travel meaning there is some differential there.

Did final install on inboard section of leading edge ply today. Went ok. I'll put up some pics after doing middle section tomorrow.

Cheers, Mick
lake_harleyJanuary 4, 2019, 2:40pm
Curiosity got the best of me, so I went searching. I never found any record of aileron deflection in my personal notes on my MiniMAX, but I did find figures of 22 degrees up and 16 down in the 1030 builder manual. It was on Pg. 13 in the "Control System" section. I also looked at the same "Control System" section on my 1100 plans and to my surprise there was nothing noted. Perhaps it's there somewhere, or maybe it's in the plans somewhere, but I might have overlooked it. In any case, since the aileron horns and aileron yolk are the same in all models (I think) aileron deflection should be consistent across the board.

Hope this helps.

Lynn
MickvdsJanuary 4, 2019, 10:37pm
Thanks Lynn