Activity Stream

Activity Stream



  1. akflyer added a post in a topic Midrange adjustment   

    I have the arctic sparrow in flight adjustable needles on my 582 so I am not a HACMAN guy, just tossed that one out there as a possible fix.
     

    • 0


  2. akflyer added a post in a topic Midrange adjustment   

    you could be right, dont quote me on the 618.. im going off a basic 2 stroke principals and the 582  
     

    • 0


  3. Deejayel added a post in a topic Midrange adjustment   

    I can do that. I'll go with 160/170 mains and pitch it to 6600. I need to verify the WOT. I'm thinking it is 6700-6750 I think I was chasing high water temps this summer so I was moving the pitch to 6800 for a baseline assessment.
     
    I thought the Hackman and the 618 didn't play well together?
     
    I can run at 5800+ rpm and the temps stay cooler, but the fuel consumption increases of course
    • 0


  4. akflyer added a post in a topic Midrange adjustment   

    Can you put a hacman on it?  Its kinda nice to be able to dial in your temps.  950 on take off seems a bit low, but your also keeping it from burning down so thats cool.  I run around 1100-1150 on take off and cruise, but I have inflight prop and mixture.  Turning 6800 WOT level is probably your issue.  I have mine set so I turn 65-6600 WOT level.  anything more than that and I get high EGTs in cruise even with the inflight mixture.  I would be tempted to up the pitch a little, and drop a jet size on the main to get your take off EGTS better yet still not unload the engine too much in the midrange as your doing now.  The high  EGTS in midrange are due to the engine not being loaded enough.
     

    • 0


  5. Deejayel added a topic in Two Strokes   

    Midrange adjustment
    I'm going back and forth with my midrange performance. Here are my stats:
     
    Rotax 618,
    WOT cruise set to 6800
    Rotax Rick 50hrs TSMOH
     
    My current installed Jetting:
    PTO main jet 165
    MAg Main jet 175
    2.72 needle jets with 15k2 needles
    45 idle jets and 2 turns out
     
    I'm about to readjust idle after I install the clutch, so we will leave that be for now.
     
    WOT on takeoff, I'm getting good smooth power and 950deg
     
    Cruise: so here's the deal. Up till about a month ago, oat temps were in the 90's and the clip on the 2nd from the bottom was giving me a perfect colored plug and good egt temps hovering around 1050-1100. Now that the oat temps are down to 80 and below, I have been noticing my temps increase as they should. Checked my plugs and sure enough, too lean for me. So I dropped the clip to the bottom option. No good. She runs way to rich and pops and burps in cruise (5600rpm). I had a 45min flight toady with those conditions. landed, shut down, pulled the carbs and adjusted the needles back down. Off to the next landing site.... Engine runs soooo nice. But temps were at 1150 and any decrease in cruise rpm and the temps go up. as expected, but I don't like it.
    I need a needle that allows me to use a middle clip option and be a bit richer than what I have now with the 15k2 on the 2nd clip.
    Or am I missing something?
    • 13 replies
    • 1,870 views


  6. looped added a post in a topic wingtanks.com   

    thanks for the reply's ,Ed to answer your questions, the tank dosent leak ,I would like to run fuel from the gas station.i have not considered caswell, have any of the members here used it and what were their results . thanks looped 
    • 0


  7. Av8r3400 added a post in a topic wingtanks.com   

    There is another option: new tanks are available for your plane made by the same company that makes them for Kitfox. Airdale has these.


    Airdale is Wingtanks.com which is why you are having a hard time getting an answer. (Unfortunately).

    We are again trying to reach out to Brett to offer help to him to rectify this problem of his. But that's a story for another place.
    • 0


  8. EDMO added a post in a topic wingtanks.com   



  9. looped added a topic in Avidfoxflyers General Hangar   

    wingtanks.com
    I recently purchased a avid mk4 that was partially built in 1999 then sat until now. from  what I have read the wing tanks should be replaced so i  have decided to buy the wingtank.com tanks the only problem is I haven't been able to get in touch with them through email is their a phone # that any of you have, or am I just excited and to impatient thanks looped
    • 14 replies
    • 1,778 views


  10. High Country added a post in a topic Steve Henry and his SuperSTOL   

    Thanks for sharing Joey, This is an awesome plane and Steve is an Awesome pilot. I was fortunate to see him perform at one of our Top Fun Flyers meetings in Nampa just after he build this one I think he only had about 4 hrs on it at the time.
    • 0


  11. EDMO added a post in a topic Vortex Generators on the wing   



  12. wypaul added a post in a topic Vortex Generators on the wing   

    Thanks Joey that was a good write-up and a good reference for anyone still thinking about VG's.
    • 0


  13. Av8r_Sed added a post in a topic RK400 Clutch Install   

    After I installed my clutch I had to reduce the idle jets to .45 to get it to idle worth a darn.  I probably would have been better off with one size smaller yet.
    • 0


  14. akflyer added a post in a topic 7-6-13 SFO   

    They land up here on the taxi ways at ANC with a regular frequency.  They have also taken off on the taxi ways and in one case I can remember 3-4 years ago, they drug the landing gear through the snow berm at the end of the taxiway as they clawed their way into the sky.  But that was in a 747. 
     

    • 0


  15. Chewie added a post in a topic Kitfox Model III Owner's Manual   

    I made a PDF version.  Thanks Doug for posting!
     
    Mark
    Kitfox III Owners Manual.pdf
    • 2


  16. saskavid added a post in a topic Vortex Generators on the wing   

    One of the things having the largest effect on the performance of vg's on the wing is this  squared velocity physics rule, so the force or power of these vortexes being generated at these slow thirtyish landing speeds is very puny compared to planes at landing speeds in the 50/60ish range.Double or triple the vg count on the wing and you will probably double or triple the efect they are currently having.May still not be enough, could also produce a detremental drag condition, or screw up the planes handllling in other areas of flight performance.(Speculation)  
    • 0


  17. C5Engineer added a post in a topic RK400 Clutch Install   

    Yes you can substitute something for the fixation pin just be careful they warn in the manual about not doing it because you risk dorking up the crank. As long as it's the same size sure you'll be fine. The rope works just fine.
    • 0


  18. Deejayel added a post in a topic RK400 Clutch Install   

    Reading the instructions a bit more carefully, I see it says a " large three jaw puller is an option".

    Cotton rope trick....the old sticking valve.. Nice. What about a drill bit or pin punch? Anyone know the correct diameter?

    Actually, come to think about it, I believe the previous owner gave me the little tool kit that has that pin! Now where did I put it.....blast
    • 0


  19. C5Engineer added a post in a topic Vortex Generators on the wing   

    Here's a little bit about the theory of VG's on the bottom of the wing and a few pics of Johns Wing
     
    http://www.avidfoxflyers.com/index.php?/topic/611-vortex-generators-on-bottom-of-wing/?hl=vortex
     
    Here's some info from an old thread I dug up as well.
     
    CCI VG’s on the Avid Flyer STOL by Larry Martin
    This is a report of my findings using CCI VG’s on the Avid Flyer STOL wing aircraft.
    Background:
    The aircraft is an Avid Flyer TD STOL wing with a Rotax 582, 3:1 gearbox, Culver 74×48 prop. Built according to the kit/plans with no modifications except for "Grove" landing gear. (heavier) Published allowable center of gravity is 11.185 to 16.5. This aircraft was at 13.5". Designed stall speed at approximately 900lbs in flight weight is 32.5 mph.
    The landing characteristics of this airplane were such that in order to affect a comfortable flare, power and additional speed was required beyond what I consider to be normal. In addition, there was insufficient nose up trim available on approach. On take-off, it was evident that the wings could fly sooner, but the airplane would not lift off. The tail could not be brought up before lift off speed, and would take off quicker from the 3-point attitude. The stall characteristics were such that when the airplane was gradually slowed to minimum speed, the airplane would sink, well above the designed wing stall speed. (Not with standing of course that indicated airspeed is most inaccurate at high angle of attack) The wing would not "break" at the stall, as most wings will. When the nose of the aircraft was "lobed" up and speed was allowed to bleed rapidly, the wing would exhibit traditional stall characteristics. It was determined that the elevator was not working sufficiently.
    After discussion with the designer of the aircraft, the center of gravity was moved to the published aft limit of 16.5" with the assurance that the aircraft was tested well beyond the published limit. For reasons of liability at that time, the published limit was set very conservatively. The aircraft was tested beyond 19.0", which can be safely used. (37% mac) The change in center of gravity helped considerably, but still not sufficient. Further to the designer’s recommendation, the elevator area was increased approximately 15% by extending the elevator aft. There is no room physically to change the horizontal stabilizer angle of incidence. Short of making a new one, modifications were complete.
    The flying characteristics at this point were much improved as measured by the following: A much shorter take off ground roll, the tail could be raised on take off with full flaps; almost sufficient elevator trim was available on approach with full flaps; and power off, full flap approaches could be safely made at normal speeds. The stall characteristics were similar, but at a slower indicated airspeed. Almost content with the airplane, but still not to the standard of performance that I thought it was capable of. I followed the studies of vortex generators.
    In the pursuit of finding the truth of if and how VGs would enhance performance, I read many studies and opinions. Some say that they help, others called it snake oil, etc. Art at CCI (http://www.vortexgenerator.net) was not in a hurry to sell me anything, but offered me aerodynamic and physics proofs and rebuttals. To say that he was patient is a huge understatement. Finally, he managed to overcome my skepticism, and I ordered a set with a money back guarantee. Art was first concerned about getting more lift from the tail, and we placed the VGs per his instructions on the flat surfaced (non airfoil) horizontal stab.
    The results of the VGs on the stab were nothing short of incredible and better result than the sum of what was done before this point. The tail was now producing more lift at all angles of attach. Subjectively, the tail felt more "alive". The take off run was even shorter, with the tail coming off the ground with the application of power. The increase of lift was objectively measured by comparing the neutral trim, hands off, level altitude minimum speed with and without the VG’s on the tail surface. A 10mph slower speed could hold level altitude with the VGs on. This was a dramatic increase in tail effectiveness. So much so, that I was able to remove 5# of ballast and move the CG .80" forward and have the same control feel. The stick position was physically further forward at all speeds, thus proving the elevators were working more effectively. The trim was effective at approach speed even with the cg further forward. (.5" cg change affects a considerable difference in this aircraft) The stall characteristics were such that the wing would stall at a higher angle, a noticeably slower IAS, and much more aft stick movement remained during the stall. Art then wanted to test the effectiveness of stabilizer end plates. There was a small subjective gain in effectiveness, but no objective, measurable results could be recorded. Most likely this was due to installation error inherent in the airspeed system. In addition to the enhanced low speed qualities, an unexpected gain in normal cruise speed of approximately 11% was attained. The top speed was approximately the same, but this is due to the large drag caused by the undercamber of the STOL wing. The airplane reaches a drag point similar to mach drag, in which the airplane will not accelerate above, or in the case of the Avid Stol, a disproportional increase in power only yields a minute increase in speed. It is not practical to fly at this speed. However; in the normal cruise range with a cruise rpm of 5400 yielded 84 mph with the vg’s on the tail. Without the vgs, the same rpm yielded 74mph. This is explained by the efficiencies of the tail.
    The next step was to install VG’s on the wing. Research shows that there is a wide range of "ideal" or "sweet spot" placement with respect to percentage of wing cord. Experience gained from others suggest that in a range from 4% to 12%, one would find that spot. CCI suggested 10% as a starting point. I initially placed them as per the supplied directions except I started at 7% and planned to move forward to 4% then aft to 10% to test the effectiveness. The results of the VG’s at 7% were immediately noticeable. The take-off roll was shorter. In slow flight, the stall occurred at a much higher angle of attach and the IAS was 5 mph slower. Again, I caution putting much emphasis in IAS, especially at high AOA due to position error. There is no argument that the AOA was much higher than ever before, and the airspeed needle was slower than previous witnessed. At 75+% power the nose attitude was extremely high and could remain this way flying at the verge of the stall. The Avid has "flaperons" which trail the wing. They are always flying, even in a stall. Therefore a subjective opinion of aileron control cannot be rendered. The Avid does not spin well and enters into a spiral instantly, so fast that I choose not to spin. I did fly a spin series, hoping that due to the higher AOA that was possible, it may spin. Unfortunately the spin qualities did not change, and with rudder application and a pivot of the wings, it becomes unstalled and spirals picking up speed very rapidly. Thus I still don’t spin.
    There was a gain in airspeed at the high end. It appears that the "stol wing drag point" was been changed to a higher speed. The old "aerodynamic drag point" is now easily overcome. I also noticed by way of control feel, and wing attitude that the center of pressure is moved forward on the wing. I replaced 5# in the tail to the original CG.
    The airplane was designed to be flown STOL. Dean Wilson designed the flaperons to enhance this ability. I use full flaperons for all take off and landings. I have landed with complete control in 20+ mph direct crosswinds with no problems. (grass strip) The VG’s do not detract from landing control nor do they negatively affect any of the flight characteristics. I am completely satisfied with the VG’s and help from CCI. Due to the satisfaction with the results, and my too busy schedule, I have not changed the VG placement from 7%. I would still like to, but it has to take a lower priority for the time being.
    Please feel free to contact me for further information. I heartily endorse CCI VG’s (http://www.vortexgenerator.net) if you want to fly the Avid the way it was made to fly!
    Larry Martin My93Avid@yahoo.com         
    • 0


  20. C5Engineer added a post in a topic RK400 Clutch Install   

    If installing the clutch involves removing the flywheel then yes you'll need a puller. I've seen guys modify existing ones to make them work. I called Rotax Rick when I did mine and he let me use his Rotax one for free. As far as the fixation pin I used the old cotton rope in the spark plug hole trick to lock the engine to break that bolt loose.
    • 0


  21. Av8r3400 added a post in a topic 7-6-13 SFO   

    The final word was plain incompetence of the flight crew in landing VFR.  They landed short.  Plain and simple incompetance.
     
    Combine this with the Asian cultural problems of pointing out failure, there was a check pilot on board, and this is the result.  The check pilot watched the entire approach and said nothing to the PIC until the crash happened.  Google the flight deck recordings to hear this yourself.
     
    Personally, I won't ever fly a Korean Airline.  Ever.
    • 0


  22. Boat added a post in a topic 7-6-13 SFO   

    My immediate thought was that they allowed the GPS to fly the airplane sense the  ILS wasn't working.  Seems the threshold had been moved 1,000 ft farther down the runway.  Putting in a number 1,000 ft in the "wrong" direction should just about cause what happened.
    • 0


  23. Boat added a topic in For Sale and wanted, you got it, I want it   

    Light Sport Aircraft Trailer for Sale
    Light Sport Aircraft Trailer for sale.  This trailer will haul your Avid Flyer, Kitfox, Zenith, or other Light Sport Aircraft - tail dragger or tricycle gear.  Excellent condition - almost no miles on it.  $2,500.  Located in Northern California.  Contact Lee: 707-743-2448   boats@hughes.net
     
     



    • 0 replies
    • 2,797 views


  24. wypaul added a topic in Avidfoxflyers General Hangar   

    Vortex Generators on the wing
    John Miller I know you posted some good info on vg's on the Yahoo site and it would be nice to have that posted here if you get a chance.

    Like John found my results were that it did not reduce the stall speed with flaps but lowered the no flaps stall to about the same as the full flaps stall. There is a difference that I did not notice at first but realized it the other day and that is with no flaps the angle of attack is much greater than with the full flaps stall which stands to reason. So wheel landings are easier and slower with the full flaps in my plane, maybe I am just a little slow to pickup the obvious.

    I used the StolSpeed VG's at about 8%.
    • 16 replies
    • 3,842 views


  25. wypaul added a post in a topic Build your own Avid Spring Gear document   

    I think that was a weight and balance spreadsheet.
    • 0