THE ALPHA JET MK2 -FRCFoamies

Discussion in 'FRCFoamies Plans' started by F1wanabe, Jan 6, 2014.

  1. I used some fishnet nylons for a pattern on a different deal
     
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  2. Rotorhead619

    Rotorhead619 Ace Pilot

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    Walk around video


     
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  3. Rotorhead619

    Rotorhead619 Ace Pilot

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  4. F1wanabe

    F1wanabe Administrator

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    Nice detail in the walk around and really nice build, Rotorhead! The AJ flies great in the wind and it looked like fun letting it hang there like you did. I'm sure you'll love the high alpha on a calm day! One other thing I noticed: that power set up is pretty quiet so you can fly in places without attracting too much attention, haha. That was one reason I did the 2s. You can barely hear that thing. Looking forward to the next video!
     
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  5. Rotorhead619

    Rotorhead619 Ace Pilot

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    2cell is in the works for sure.
     
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  6. Marshall06

    Marshall06 Airman

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    Awesome looking plane. Ordered the plans last weekend, picked up the print out of them yesterday and got all the pieces already cut out. I'm not sure how far back on the outer edge of the upper wing is glued down to the lower wing edge ... starting at the rear of the outer edge, is it glued all the way up the the score line for the flap/fold? Also, speaking of the flap/fold, is only the inside 2.5 inch edge glued down against the sloping side of the top piece?
    Thanks
     
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  7. F1wanabe

    F1wanabe Administrator

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    Marshall. the best thing to do is line up the rear tips of the top wing and glue together the edges right up until the curvature makes you squeeze the top wing down with excessive pressure. But, I have measured mine just for you :D And here it is- 6 1/2 inches from the rear should do it!
    20180227_185012.jpg
     
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  8. F1wanabe

    F1wanabe Administrator

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    Its a long way back to the build pics that JettaManDan posted in post #1, so just wanted to make sure that you saw the correction Dan made in his build pics? The servos should be on the outside of thre central intake structure like this as shown in red....
    standard (1).jpg

    As opposed to this...
    standard (2).jpg

    Having servos places inside like the second picture can create clearance issues with the rudders and having the mass of the servos as far out as possible creates a lot of added stability in high alpha. Rotor head seems to have had good luck with placement inside, but Dan and others have had issues with that placement. Good luck!
     
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  9. Marshall06

    Marshall06 Airman

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    That helps a lot, thanks. Yes, I noted the placement of the servos/pushrods in the beginning of the build thread here .... I'm on page 41. Regarding the servos, I'm still deciding how far back to place the servos to give it optimal balance with the CoG.
    Thanks again.
     
  10. F1wanabe

    F1wanabe Administrator

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    I have found this to be really good placement for cg and allows for replacement or adjustment without taking apart the plane.
    20180228_193648.jpg
    Plus, if you are a fan of high alpha as I am, then a more forward CG does wonders for stability. Our CG mark is a good compromise for the whole performance envelop but go a little forward for high alpha and a little back for lots of inverted and aerobatics. Placing the components as close to cg allows for the maximum flexibility in battery placement which is what I like!
     
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  11. F1wanabe

    F1wanabe Administrator

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    Oh, and that's awesome that you are reading through the thread! I do that with every new plane just to get a better understanding of the peculiarities of the plane before I build. And good tips as well.
     
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  12. Marshall06

    Marshall06 Airman

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    Thanks for the tip on servo placements ... and like you I always read the whole thread, always learn things that help.
     
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  13. TomMonton

    TomMonton Administrator

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    Novel approach too.

    Thank you and I truly appreciate hearing you mention this. One of the biggest reasons we post this stuff is for others to follow and learn from our proven mistakes.

    Looking forward to seeing your new bird :)
     
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  14. Marshall06

    Marshall06 Airman

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    The weather finally gave me a break and was able to maiden the MK2 yesterday. It handled wonderfully .... flew right out of my hand and needed only minimal trimming!

    I just purchased and downloaded your DE HAVILLAND MOSQUITO and hope to start on it later next week. It will be my first dual prop scratch build... only have 31 pages to read on that build thread :) MK2 JET.jpg
     
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  15. F1wanabe

    F1wanabe Administrator

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    Haha, thats not that bad actually since the Alpha Jet thread is 95 pages! The mosquito really flies well especially with counter rotating props. It'll take off straight up out of your hand as well. The original Mosquitos did not have counter rotating props and take offs were a little shaky from what I read. Those two huge Merlin engines both torquing the same direction must have been crazy. But I felt really comfortable even banking and yanking it. I hope you enjoy the build- its like a piece of artwork!
     
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  16. Bobfrog

    Bobfrog Airman

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    Marshall

    Isn't this plane amazing! I maidened mine last weekend and today got a few more flights on it. Super easy launch and flight characteristics are awesome both in low speed and higher speed. An absolute dream to fly. Experimented with more slow flying today and had it just barely moving and in complete control. Everyone at the field I fly at were duly impressed and I'm not that experienced a pilot yet.
    Thank you FRCFOAMIES for such a great design.

    To anyone who likes to fly:

    BUY THE PLANS AND BUILD THIS AIRPLANE. IT IS A JEWEL!!!!!!
     
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  17. F1wanabe

    F1wanabe Administrator

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    Wow, Bob, that is great! The slow and low flying is what Jay and I were concentrating on with the MK2. The lower and slower the better! The lack of wing rock really gives a lot of confidence because once the wings start wagging I tend to start predicting how I will try to recover if it drops. If the wings don't rock then you just concentrate on where the plane is heading and the next trick. Glad you are having such a blast- that's what the Alpha Jet is all about! Have you tried inverted flying? This is the first plane I did inverted high alpha with! I built a twin prop version of the mk2 and it was nice but a little heavy. This summer I plan on doing another twin with the Mig 29 power system which is light and powerful. The counter rotating props combined with the built in stability should be awesome!
     
  18. Bobfrog

    Bobfrog Airman

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    Haven’t tried inverted yet. My skills are not developed enough for that but I will try it when I feel confident.
    You did a great job on the design. Thanks for all the fun!

    Now I want to build the MiG 29 and give that a shoot.
     
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  19. Rotorhead619

    Rotorhead619 Ace Pilot

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    Well today I made an oops!!!!! So long to my V2.

     
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  20. F1wanabe

    F1wanabe Administrator

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    Oh man, that sucked! I thought for sure you would have gotten a decent flight out of that without the stabilizers! I guess I was wrong. I have a test video somewhere of the twin prop alpha jet mk2 with broken stabilizers and the counter rotating props kept it stable enough to fly. I'll look for that video. Anyway, looking forward to the next one!
     
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FRCFoamies Plans FRCFOAMIES ALPHA JET MK1 Apr 24, 2012

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