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Everything posted by nlappos

  1. nlappos added a post in a topic MATCO Tail wheel shimmy   

    1avidflyer, what did the fiberglass spring weigh? Seems like a good way to cut a pound or two.
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  2. nlappos added a post in a topic Cabin Heat   

    ak, they say it is 8000 watts, which is 27,000 btus, but the  heat is produced by burning the fuel. You agreed with their fuel consumption number, which is stated at .24 liters per hour (about .06 gallon per hour.) Diesel fuel has 139,000 btus in each gallon, .06 gallon has .06 x 139000 = 8340 btus. Even the Chinese cant make heat from air.
    I guarantee either the fuel consumption number is wrong, or the heat it produces is wrong, and you said it burned a bit less than a gallon a day, which agrees with 8000 btu.
    I bet they have a typo and like it because it sounds better. I have seen them do this with electrical stuff, and computer stuff too. I am not saying they like to exaggerate, don't get me wrong.......
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  3. nlappos added a post in a topic Cabin Heat   

    Some thoughts about that diesel heater:
    1) The heat value makes no sense, at 0.24 Liters per hour max diesel flow, that would be right at 8000 btus. (diesel has 139,000 btu's per gallon, .24 liters is .06 gallons per hour. akflyer confirms this flow when he saw 1 gallon every 24 hours, that is about .05 gal per hour) . The claimed 8000 watts is about 27,000 btus.  Even so, I would bet the 8000 btus it really gives out is nice heat.
    2) Putting heater, a flame source, in the cabin is near suicide, anything goes wrong and its toast.
    3) Putting it right outside (like akflyer's belly pod), with a firewall between it and the cabin would be pretty safe.
    I have the Avid "stock" heater funnel off the left radiator and it works well down to about 25F (all I've seen so far). If the water temp drops to 145 or 150, the heater falls off too. As a result I block my belly rad off (at 35 deg takeoff, I have it half blocked). Most important was lifting the top cowl and blocking all the area behind the firewall up to the windshield off so the drafts almost stop. I also sealed the door leading edges with stick-on door seal, works well.
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  4. nlappos added a post in a topic MATCO Tail wheel shimmy   

    My high speed shimmy stopped when I tightened up the pivot nut enough to damp the wheel pivot, but at that happy place where the TW still castored and allowed me to turn. Took a little experimenting.
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  5. nlappos added a post in a topic Avid C HH wing build 101   

    There are ethanol capable fiberglass tanks, I have them. Much better than aluminum wing tanks, which are reported to not flex and therefore cause tank cracks.
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  6. nlappos added a post in a topic MATCO Tail wheel shimmy   

    1avidflyer is quite right. One way to explain it is to be sure the axis of pivot of the TW is as near to vertical as possible. The spring often bends flatter with time, so getting it bent steeper, so the wheel stands more vertical, is a strong contributor to fixing shimmy.
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  7. nlappos added a post in a topic MATCO Tail wheel shimmy   

    I have a similar tail wheel (the single arm version) and had to cure the TW shimmy when first installed. The shimmy is more prevalent at higher speed, but can be cured by crushing the washers a bit more below the main nut, #3 in the photo. Try going one more flat on that castellated nut.
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  8. nlappos added a post in a topic Becoming a rejuvinated bird   

    mack55, Wasau Spring can get you the tail spring custom made. I bought my springs from him and he was great.     (715) 845-6335
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  9. nlappos added a post in a topic Tail Leaf Spring Maule Tailwheel   

    contact Al at Wasau Spring, he will make whatever you want, and his customer service is first class:,  (715) 845-6335 
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  10. nlappos added a post in a topic Replacement of Jesus Bolts on Fuselage Wing Strut   

    I looked over mine this last year and saw no significant damage or wear, after 22 years and maybe 800 hours. I think they are nicely oversized for the job.
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  11. nlappos added a post in a topic Rotax 582 engine failure. Can you solve the mystery?   

    He waited about 5 seconds during the climb as the engine wound down before he reduced to angle of attack, that frittered away his flying speed and his lift. You can watch the stick move progressively back as he basically just stalled the aircraft in place. Had he positively lowered the nose when he first heard and felt the power loss, he could certainly have landed dead ahead with no damage.
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  12. nlappos added a post in a topic Rotax 582 engine failure. Can you solve the mystery?   

    One thing for sure, a little flare before touchdown would have made this a lot better outcome. Plunking down on the nosewheel with no flare is a real no-no. Failure to actually fly the airplane is the principle cause of the crash, once the engine seized.
    And thanks Cloud Dancer, this is a great thread, and those guys who did the teardown are fantastic pros.
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  13. nlappos added a post in a topic Nimbleone2   

    TRICYCLE GEAR - 2017 AVID FLYER SPEEDWING • $16,000 • FOR SALE • 2017 AVID FLYER SPEEDWING N9695Q Length:  17’11” Width wings folded:  7’10” Height:  71” Empty 565 lbs Gross 1050 lbs Useful load 485   34 gal of gas Cruise 100 mph Burns 4.5 gph 7.7 hrs endur Rotax 582 UL DCDI 65 HP (41 hrs on the eng & airframe) Gear Box Type B 2.58:1 Stainless firewall w/ Fire exting 3 bladed composite scimitar prop Jet hot coated exhaust Grt sport efis Garmin 296 Narco AT165 digital trans Ditel digital comm Digital engine gauges Elec elev trim Whelen nav lights with strobes Flown 40 hours for phase I First flight Dec 19, 2016 • Contact Stephen H. Irving - US ARMY, Owner - located Clarksville, TN USA • Telephone: 228-209-4561 • Posted November 8, 2018 • Display Specs Page • Show all Ads 

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  14. nlappos added a post in a topic What oil for rotary valve?   

    I should have added that Rick said to watch the oil level in the small reservoir. If it starts going down, that says you are burning the oil, so then switch to the 2-stroke oil (Amsoil) to prevent any dirty burning. I have about 10 hours so far, the oil level hasn't budged. My old 582 (using Lucas 2 stroke oil) never showed any level change in 160 hours.
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  15. nlappos added a post in a topic MK IV Aerobat speedwing spar gouge/repair   

    Yep, you're right Jeromef, my bad. This time I actually looked at the recommended splice and agree. A real repair splice should have an external sleeve the same thickness as the spar but with a larger diameter so it slips over the spar. It should run about 2.5 diameters long on both sides of the repair (5 diameters total length) and should be bonded to the spar with a structural adhesive (Scotchweld is good, I think). The deep scratch should be blended down to a smooth surface, and the splice fitted over it without scoring any of the material, bonded tightly with the adhesive squeezing out.
    This is probably overkill, because the area is before the strut, so the spar isn't in much positive bending, more likely it is in compression. I think the highest stress section of the spar is immediately outboard of the strut attachment.
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  16. nlappos added a post in a topic MK IV Aerobat speedwing spar gouge/repair   

    That splice will be stronger than the original spar. Go for it. In the future, transport the wings by suspending them lengthwise from the truck sidewall. I hung them at eye level, lengthwise along the sidewall of the truck, using nylon straps around the leading edges. They survived nicely.
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  17. nlappos added a post in a topic Avid B Sheriffs Auction on 10/2/18. 10:30am.   

    "Somewhere in between these two extremes lies your CG range" said Cloud Dancer. Right on. Range, not tolerance. So you do agree.
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  18. nlappos added a post in a topic What oil for rotary valve?   

    Rotax Rick ships with regular 30 w oil, since the rotary valve lube doesn't get burned. Says it is better lubrication, and not compromised by the need to burn clean.
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  19. nlappos added a post in a topic Avid B Sheriffs Auction on 10/2/18. 10:30am.   

    Cloud Dancer,
    The CG range is not really a tolerance band, like + .010" is a tolerance. The difference is that the airplane can operate across a wide band of speed, weight, altitude and CG, and none of them are tolerances, they are approved operating envelope areas, each with a horror story if exceeded.
    The forward CG limit is found by testing the aircraft at slower and slower speeds in landing condition, until the up elevator is no longer able to hold the nose up. This is because the up elevator is fighting the nose down tendency of that forward CG, and as speed reduces, the force the elevator can make to fight the nose down is reducing. Another possible way that forward CG can be limited is by crash loads, which stress the gear unevenly as the weight is shifted across the CG range, especially a nose wheel in a nose dragger.
    The aft CG limit is chosen almost the same way , but in that the elevator cannot stop the nose from popping up as the landing is made. If you fly an Avid at its aft limit, the nose in a landing flare tries to go to the sky, it is a spooky feeling. Some have said aft CG makes the airplane land slower, which is not correct, but aft CG does make the aft stick needed for high angle of attack (slow landing) much easier to get too. Another limit for aft CG is the ability to get out of a spin, because as CG gets further aft, the spin gets flatter, and the forward stick to recover gets less effective. Far enough aft CG and a stall can easily become a flat spin, where recovery is impossible. Test pilots put a spin chute in the tail and pop it out to make the spin stop if they go flat - a wild ride!
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  20. nlappos added a post in a topic W&b doneso   

    Terrific work, Matthew. I always wonder why people shy away from the rotax engines, they are great!
    What is your Max Gross Weight?
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  21. nlappos added a post in a topic Flaperon Control Break   

    I think the loss of one aileron would reduce the control power in half, and on short final, the change would catch many of us by surprise. This could very well lead to the case where the roll control was very sloppy, and ground contact becomes more likely.
    I think the evidence that the right flaperon control rod sheared, and the flaperon went neutral (right on flywise) would be fairly benign if it happened in cruise and you had some time to work it out.
    I doubt that the flaperon breaking at the control rod would make more drag on the broken side, but it would make an unbalanced drag, where the broken right flaperon would have low drag and the unbroken left one would have high drag, with the flap setting. You would think this could make the aircraft yaw left and roll left(strong dihedral effect), but the fact that the left had lots of flap setting would look like lots of right aileron, so the aircraft would roll right sharply. 
    It stands to reason that the rod would shear with large flap input, since the twisting of the rod is how we fight the normal flap force to streamline, so the torsion on that rod would be a maximum with high flap settings.
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  22. nlappos added a post in a topic Mk iv or C?   

    Matthew, gross weight is by design, sort of, but also what the builder declared and then flew in Phase 1. The FAA paperwork is the final say, but then that means if the builder took a C that Dean Wilson meant to be a 1050 lb C and then flew it at 1200 lbs, a wise next owner should think hard about that. We could get into spar thickness and rib spacing and fuselage member thickness, but I don't know those details very well.
    I think the 1050 is the right design weight for a C, and that your paperwork agrees so that is a good number, and the right one, Matthew.
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  23. nlappos added a post in a topic Mk iv or C?   

    A very important attribute is the useful load, regardless of the model type. What is the empty weight and max gross weight? A good Mark IV is about 550 empty and 1150 max gross, for 600 lbs of useful load. Many C's have about the same empty but only  950 to 1050 MGW
    Here is a site that shows the major changes:
    Here is a list of the MK IV differences:
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  24. nlappos added a post in a topic Cabin Heat   

    It came with the kit, Matthew. Item F-78 on the parts list (I can't find the valve on the list)  I offer mine up for someone to make a splash from, it is fiberglas, about 1/16" thick, nothing fancy. I can also just photo and sketch it in detail, the only fancy interface is the rectangular flanged face that bolts to the radiator, and the circular tube for the orange tubing. More complex is the fancy spring loaded flapper valve that mounts on the firewall.
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  25. nlappos added a post in a topic Cabin Heat   

    The original heater seems to work well. I tried it yesterday and was surprised at its output. I also dammed the space between top of the firewall and the windshield bottom to stop the horrendous drafts, using cardboard and tape.
    I used a car choke cable to pull open the firewall valve, and located the inlet low on the firewall between my feet.

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