Acro Sight

Discussion in 'Aerobatics Talk' started by smizo, Mar 2, 2018.

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  1. Mar 2, 2018 #1

    smizo

    smizo

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    Ok guys working on my aerobatic sight now that I can fit the bird in the hanger with one installed. So, having never flown a contest or been judged from the the ground here’s a question. I’ve talked to a bunch of people and read a lot preparing. Being a non “round wing” airplane I’ve heard the upline may be flown not exactly vertical with the airplanes “level line” or, the aircraft longeron flight level may not be vertical level and the plane should be judged by the chord line of the wing. Is this just theory? Will the airplane present vertical when the chord line is flown vertical? So, should I build my sight set to the chord line of the wing, and then make adjustments with ground critiquing? And...... for bonus points, what am I building the sight out of ;)
     
  2. Mar 2, 2018 #2

    Cameron

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    I'd recommend starting with setting your sight parallel with the chord line and go from there. I think I started with mine parallel with the top longeron on my ASII and I was getting called positive. Be sure to build some adjustability into your site.
     
  3. Mar 2, 2018 #3

    PittsDriver68

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    Aerobatic Judges are tasked with using the "Zero Lift Axis" to grade vertical and 45 lines. That is NOT the top longeron.

    That said, the only way to adjust your sighting device to get you to the highest scoring vertical attitude is to fly some practice flights in front of some of your local IAC chapter's Judges. What they see as "vertical" is what you should adjust your sighting device to.

    Best of luck,

    Wes
     
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  4. Mar 2, 2018 #4

    Eric_Anderson

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    I would start with the longeron and go from there. Practicing with the sight a degree or two off will not result in negative learning. So, it really it doesn’t matter...yet. During a box day (hopefully with zero wind) we can dial it in before a contest.
     
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  5. Mar 2, 2018 #5

    cwilliamrose

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    I think Eric's advice is sound for the lower categories. If you're doing vertical rolls you don't want to be significantly off vertical because it will lead to habitual control inputs that will have to be unlearned when you get the reference properly set.
     
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  6. Mar 2, 2018 #6

    smizo

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    Thanks guys!
     
  7. Mar 2, 2018 #7

    Eric_Anderson

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    I think Bill is being nice. I take back the part about negative learning because his statement holds true for the lowly hammerhead as well.
     
  8. Mar 2, 2018 #8

    Dennis Flamini

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    Last edited: Mar 2, 2018
  9. Mar 2, 2018 #9

    grassroots

    grassroots

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    Hand spun Brazilian Rosewood dowels meticulously lacquered and buffed would look killer and freak people out way more than your red prop tips.
     
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  10. Mar 2, 2018 #10

    race38

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    Of course, you could just call Bill @ Dent-Air and he'll mail you one before you can fire up the autoclave and vacuum pumps!!! :p
     
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  11. Mar 4, 2018 #11

    Skippy

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    Carbon fiber, so it won't rust like mine seems to do all the time.
     
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  12. Mar 4, 2018 #12

    grassroots

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    I guess there's a chance he'll look into that. ;)
     

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