FoxDB

Members
 View profile  See their activity

  • Content count

    100

  • Joined

  • Last visited


Posts posted by FoxDB

  3. Posted

    Efi,

    I like your baggage area. Did you build from Plywood? I put one in the same location but after the plane was finished so it does not look as nice as yours and is built of Lexan.

  4. Posted

    I have not installed them yet, But what I gleaned from discussions is that they are not as effective as they could be due to the scalloped forward wing area. My Mod 1 has some areas of non scalloped due to wing tanks and locker plus the builder used aluminum in some areas then used the extra false ribs to reduce the scallop in the other spaces. I also see that due to forward C.G. and shorter distance to tail on Mod 1 the elevator loses effectiveness and you can not explore the benefits of the V.G.s. This I believe is why Joey installed a larger elevator.

  6. Posted

    Joey,

    I have hand propped my 582 many times. Low battery, bad starter relay and to cold to for starter to crank. It's not a one pop crank though you have to get a few comps at least.

  7. Posted

    I have a gray head 582 w/ 3/1 C box and IVO prop in my Kitfox mod 1. I do not have a pull starter just the electric. I have shut my engine down in flight and restarted using the electric starter, It worked, just had to hit it when the prop stopped briefly. I also started it using prop turning in the wind but I had to nose down to get above 80 MPH before it would turn fast enough to start. PUT IN THE ELECTRIC STARTER.

    IMHO

  8. Posted

    I have a gray head 582 w/ 3/1 C box and IVO prop in my Kitfox mod 1. I do not have a pull starter just the electric. I have shut my engine down in flight and restarted using the electric starter, It worked, just had to hit it when the prop stopped briefly. I also started it using prop turning in the wind but I had to nose down to get above 80 MPH before it would turn fast enough to start. PUT IN THE ELECTRIC STARTER.

    IMHO

  9. Posted

    Tjay,

    I added an electric trim tab to my Tailwind for 1 reason. Jesus bolt if it fails with an electric trim tab you have a chance to survive. That said I have an aero trim system on my Kitfox 1. It uses springs and was easy to install and the only mod was a place to mount the control knob and a tab for the spring on the control.

    Dave

  13. Posted

    It needs to be away from the leading edge. (Farther Back) Air flow in front of the leading edge is deflecting and will cause errors. I have an AOA indicator installed on my Model I and it is forward of the leading edge and indicates twice what the AOA is and is designed that way to increase readability.

  14. Posted

    Leonard,

    The Bungie is one of the most travel ideas and is well proven, the only down side is no re-bond dampening. I used a scaled down version of the Bearhawk die spring in a canister that allows more stroke than the external die spring designs and re-bond dampening. The disadvantage is the difficulty in tuning and there is a point were the spring becomes solid. I currently have it designed to 3gs before the spring goes solid. Am considering what spring or combination of springs would change this to 2gs. I really like the design of the Roberts Struts with the Fox Float and bungie or the TK Racing all air shock. The cost is high however. I may build some all bungie struts just for S & Gs.

    Dave

    1 person likes this

  15. Posted

    The plastic leading edge was for use on the Mod IV wing and was never intended for Mod I thru III. I have heard somewhere that aerodynamically it makes no difference on Mod I thru III and is just cosmetic.

    Dave

  16. Posted

    Well the plus is your front gear leg looks like 1-1/4, The horizontal tube will help as installed but would be better if it went straight from hole to hole, the higher cabane to strut attach will require less stroke but more load so it may work fine with the springs you have. For the type of flying your talking about it should be fine. A bad landing is hard to quantify, I bent an original gear leg and axle of the stock gear by a poor landing at gross at the airport. I bent my fuse with the bush gear at around 800 Lbs with a bad landing in the bush, the gear however was fine. Good luck and fly right.

    Dave

  17. Posted · Edited by FoxDB

    Joey,

    Would really like to see some photos of your TK struts. Did you go with 4" or 6" stroke? Also please consider Leonard's suggestion of a horizontal tube between the forward gear attach points.

    Dave

  19. Posted

    Akflyer, 

    I was evidently not clear enough in my post. The angle of the cabane was not what the problem was for me. Problem was the gear leg compression not inline with the longeron but pushing under it caused torsion to the longeron. The cabane does not help the issue either as the legs are in tension and are contributing to the torsion issue in most designs. However I actually provided an independent cabane attach point to allow an inline pull on the longeron.

    Hope this helps the explanation, I can take some photos and attach if it would help. I think the best would be the horizontal tube you mentioned to keep the gear attach points from coming together. The angle of the cabane has more to do with the loading on the bungies and the stroke needed during gear deflection. A lower strut attach point with require more stroke for a given tire movement but will require less load.

    Dave

  20. Posted

    I know I have posted this before but, the Kitfox and Avid fuselage attach points are not angled properly for a cabane type gear. This causes torsional forces to the longerons. I know this by experience.

    1 person likes this

  21. Posted · Edited by FoxDB

    Not trying to oneup just educate. Elasticity is prior to failure of the material in yield strength. This is why we see such wing defection in an airliner in turbulence, but it does not fail due to the yield strength of the aluminum alloy. Hardness is not stiffness.

    1 person likes this

  22. Posted

    Just a side light with no bearing on the spar issue but the flex (or deflection) of the material does not have to do strength but modulas of elasticity. For aluminum that is 10 x 10 to the 6th.

    Dave

    1 person likes this

  25. Posted

    TJay,

    The builder of my mod I also extended the vert. and rudder as you have down. This caused an excessive deflextion when applying rudder at cruise. The mod IV tail was strengthened to account for it. I added guy wires to stop the deflection.