THE ALPHA JET MK2 -FRCFoamies

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

  1. kwebersole

    kwebersole Airman

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    Hey everyone i did the maiden flight today (with only one set of wings) and it worked very well, it was very stable, and it did high alpha VERY good! thanks
     
  2. F1wanabe

    F1wanabe Administrator

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    Kwebersole, after you add the top wings see what happens!

    www.youtube.com/gstrysky
    www.frcfoamies.com
     
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  3. kwebersole

    kwebersole Airman

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    ok i will try that
     
  4. BarryM

    BarryM Ace Pilot

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    F&S
    I have probably the loudest models at the field, even beats the 50cc models. I am already flying the Alpha 2 with the standard prop slot, if I cut the bow-tie forward and back from the existing cut out would that be O/K?

    Barry
     
  5. F1wanabe

    F1wanabe Administrator

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    Barry, the alpha jet is loud! The bow tie may help a little but a lot of it has to do with the sound of the airflow between the wings. Mine sounds like a vacuum cleaner! That's where the magic is made. May I suggest that you try a 2s set up if you have the need for a quieter alpha jet?

    www.youtube.com/gstrysky
    www.frcfoamies.com
     
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  6. DavePowers

    DavePowers Administrator

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    Bow-Tie does wonders for the noise and performance.
    Also look for motor mount vibration on the screws and such.
     
  7. FatherAndSons

    FatherAndSons Top Gun

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    Yes, cutting the bow tie forward and back of your existing slot can only help, but...as Greg said above. The Alpha Jet is a loud plane due to its design. The prop is pulling air over two wings and two slots. I think Greg is also probably right about the best solution for a quieter plane being a 2s setup.

    Opening up your prop slot and rounding or tapering the slots can only help, but...while the Alpha Jet may be one of the favorite planes at the field, it will likely never be the quietest plane at the field o_O:):eek:
     
  8. BarryM

    BarryM Ace Pilot

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    Thank you gentlemen, I kind of like the 3 cell power, gives me that little extra on the vertical and gets me out of trouble quicker, I think..... besides:( don't have any 2 cells. I will try the bow-tie cut out, but I suppose I've had the 50cc noise for a long while....so my turn for awhile !!!!
     
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  9. 4props

    4props Rookie

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    My MK1 flew again :) I wasn't going to bother but then got the UHU-POR out and some epoxy (the motor mount had come away from the foam), 20 minutes later and it was in one piece.

    I tried it out today (first time without the gopro to catch my flights) the wind took it on launch, it then ended up side down 4 ft away 3ft off the ground. I am not quite sure how I managed to get out of it but I spun it and flew off :) Perfect.

    It is a little quieter with a new prop and bow-tie cut outs (I also rounded the edges) but very much a screamer. Love it :)

    Thanks guys
    Darren
     
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  10. skelator

    skelator Cadet

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    just printed my plan found a shop that print $1.99 per sheet of A0 and I went printed 3 copies lol talk about greed :p, will be building this over the weekend and practice flying it, how well the plane handle loop? we have a loop competition next month thinking of competing :D
     
  11. F1wanabe

    F1wanabe Administrator

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    Wow, that is cheap! What part of a loop are they judging? The mk2 loops really nicely. Smooth and tight! If you are looking for tumbles, you may want to print off the mk1 elevons and put them onto the v2. We reduced a little of the tumble-ability of the mk1 in order to give a smoother, more precise response on the mk2. But, if you don't want smooth and refined, but prefer crude tumbles ;-) then try the mk1 elevons and a rearward cg!

    www.youtube.com/gstrysky
    www.frcfoamies.com
     
  12. F1wanabe

    F1wanabe Administrator

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  13. skelator

    skelator Cadet

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    wow inverted loops sound fascinating :D, but I don't think I can pull off such stunt lol, they only judge on how many loop you can do per run, so normally big plane will need to fly high with alphajet I guess low and slow would give it and advantage unless they decide to disqualified me lol
     
  14. OzFaxFlyer

    OzFaxFlyer Cadet

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    ..and speaking of hovering.....although on a slightly larger scale.....

    www.liveleak.com/view?i=77e_1389637750
     
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  15. whatmovesyou

    whatmovesyou Top Gun

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    Thanks OzFaxFlyer for the video. That is probably one of the better videos showing the flow patterns in different maneuvers.
    Also enjoyed the landing sequence since it show how the canard is being used. That is what I am hoping to duplicate with my F-22 with LE slats, canard and landing gear.

    If you go to 2:22 in the video, that maneuver, I have tried before and no luck in duplicating, and this video just gave me something I never saw/caught before. Now, I will have to pull out my dual barrel TV 64's, and see if I can do it. Thanks to you.
     
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  16. sgmoran

    sgmoran Ace Pilot

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    Thanks for sharing that video! Amazing demonstration. I was at the Paris Air Show in 1995, the Russians always put on the best show, our military pilots are not allowed to fly like that in an air show. I was talking to a F15 pilot and he assured me "off the record", it was capable of the Cobra maneuver the MIG29 did in front of us. I look forward to whatmovesyou finally figuring this out for the rest of us.
     
  17. whatmovesyou

    whatmovesyou Top Gun

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    First of all, did you catch the tight loop (called an "E" when doing pattern maneuvers like the letter "e") where he brings the gear down and up so with TV, he produces a sharp E. Interesting approach.

    As for the Cobra maneuver, I have tried and lack the brute power needed to exit at the same altitude with TV. I have got it past 90 degrees, but on the way back over it drops and rolls out due to lack of power. I even found an article where a Russian pilot describes the procedure in detail which help me improve, so maybe if the thrust increases on our fans and batteries, maybe.

    Canards is the key in the video. As he pulls up, he tv yaws it and 1/4 rolls it, watch the canards. They are highly deflected(vertical to the bottom of your video screen) and stay high until he comes out of it and then they go back down. I have been exploring canards (wrong and right way) for a couple of years for improving high alpha and using them as a second set of elevons which allows the plane to do some wild gyrations causing undue high stresses(even lost a 4s battery, ouch.) No one else bothers to try it, but it works. A naval pilot has done spin tests for his thesis showing it does work with certain restrictions.

    After I finish my attempt to use canards for pitching the nose up to get airborne in grass using gear and increasing stability on my LE slats for STOL?, then to play with this maneuver and elevons.
     
  18. F1wanabe

    F1wanabe Administrator

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    The alpha jet mk2 doesn't do cobras ;-) Before we return the thread to the alpha jet, I'll post my cobra video. I posted my Mig 29 v1 edf cobra maneuvers video a couple years ago, I'm surprised you didn't see it, Whatmovesyou! Piece of cake! It's important to keep the polar moment high, ie: keep edf rearward and battery forward. This will cause the nose to begin to fall backwards after it passes 90 degrees. Then you use tv to bring the tail back up.


    www.youtube.com/gstrysky
    www.frcfoamies.com
     
  19. whatmovesyou

    whatmovesyou Top Gun

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    If you remember the discussion about a year or two on this site, the cobra requires you to come out on the same level plane as you enter. Like me, you drop out and recover at a lower altitude. Hence, you have the same problem that I have, not enough power in the TV to hold exit altitude the same. I did all that stuff that you mentioned, even with TV in rear.
    Now back to the mk2 site.
     
  20. F1wanabe

    F1wanabe Administrator

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    The real mig does lose altitude and the definition of the maneuver is to keep "approximate" altitude. But, as this picture shows, the plane can resume the same altitude as when it began the maneuver, but during the maneuver actually gains altitude...
    [​IMG]
    In the long lens shots you may not have the point of reference, but here in this video with smoke trailing and background clouds to help you see the drop in altitude. Its physically impossible to maintain altitude once the plane resumes level flight until the airspeed can be built up again. and you see the pilot dipping the nose to build airspeed as soon as the maneuver is completed. That's what you and I got in our cobra maneuvers!

    In the last couple seconds of this video the horizon gives you a great indication of how much altitude they gain during the maneuver...
     
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