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Thread: Lessons Learned at the Talkeetna Fly In - A Bit Too Slow

  1. #81

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    Im not trying to stir the pot here, just trying to understand- Dave, if the wing is primarily flying on reaction lift in these ultra-high alpha regimes, (which I tend to agree with, by the way, bring a RC guy I get what you're saying), why do the slats enable these angles of attack? I thought the whole point of the slat was to keep the air attached to the top of the wing longer? Just something I've been mulling over; maybe I misunderstood what you were saying. I'm not disagreeing, just trying to understand...

  2. #82

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    About the 9 min mark is the smoke trail with slats.

    https://www.youtube.com/watch?v=q_eMQvDoDWk
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  3. #83
    Dave Calkins's Avatar
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    Ak49, yes the purpose of the slat is to delay separation of airflow at higher angles.

    I believe that in ground effect (commonly one half wingspan from the ground) reaction lift is the king.

    I have been thinking about how the slat "cups" the air and sends it over the wing. What surprises me is that I have never sensed any "pitch up" when the slats deploy. I

    Stewart B. We are not literally hovering on the propeller, or are we? Kazoom seemed to be the brief time I flew it. Yes, its probably over $200k.
    Last edited by Dave Calkins; 06-02-2017 at 09:13 AM.

  4. #84
    Eddie Foy's Avatar
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    Dave,
    Define what you are calling reaction lift.
    "Put out my hand and touched the face of God!"

  5. #85

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    You're the one that brought up hovering on the prop. I guess I'm stuck in the old school thinking that airplanes with wings require some element of airspeed to make the lift required to hold the airplane up. I like the idea of slower control envelopes opening up new opportunities and am personally invested in it but with all airplanes there is a point where too slow is too slow, as demonstrated in the video.

    Here's a good paper discussing lift.The science is interesting and the delivery is amusing.
    http://mb-soft.com/public2/lift.html
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  6. #86
    Dave Calkins's Avatar
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    Eddie. The relative wind hits the bottom of the wing and is vectored down.

    Have you flown a slatted airplane? I had asked you that several times. Thanks.

  7. #87
    Dave Calkins's Avatar
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    Stewart. In "high alpha flight" ( what Tom demonstrated in Talkeetna), propeller thrust is providing a portion of the weight lifting.

    the more thrust, the more weight lifting. Any argument?

    but the extra thrust must be vectored (lotsa rudder)

    .....and if vectored to Cause a yaw, the flow increase under the left wing may have picked it up. And certainly the increased thrust would be assisting in lifting the a/c.
    Last edited by Dave Calkins; 06-02-2017 at 10:06 AM. Reason: Clarifying withore words!!!!?

  8. #88

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    Quote Originally Posted by Dave Calkins View Post
    The relative wind hits the bottom of the wing and is vectored down.
    .
    Dave, from sailing in days gone by I understand relative wind and from that a couple of questions and observations.

    When the realitive wind is vectored down does it attach and stay attached to the bottom of the wing making for an appearent wind lift vector or is it deflected away leaving the bottom of the wing as a turbulent zone. I was fortunate to meet and fly with Wayne in the prototype for a few days and was amazed watching the slats come on and off and saw part of his string study video and remember the tops of the wing but not the bottom, or did he care?

    With fast boats tuned sails can work at very high angles of attack (close to the wind, say 35 degrees off) but you can't start with that high of an angle of attack, you have to round up to it with attached flow over the top as the realitive wind angle swings forward (reverse of powering downwind on a broad reach for amayzing speeds. When going up wind with a Jib if you loose the attached flow over the chord it immiediately back winds and you're toast in short order. The confusing part here to me is a high performance boat will point higher into the wind without a jib than with but the speed rally falls off, so it would seem to my pea brain that the slats are not truly generating lift as an extension of the wing like a jib does both with attached flow and with slot flow but floating slats are rather forcing more air along the top chord to stay attached to the wing via the slot only. So if that's the case I can absolutely see why the stall would be so very abrupt.

    Does this make any sense at all?

    Kirby
    Last edited by OLDCROWE; 06-02-2017 at 11:39 AM.
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  9. #89

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    Interesting. I don't know enough to comment on what the prop's contribution is. To me it creates airspeed and that allows the wing to provide lift. I can control the airspeed and lift by changing the AOA and power but there's a limit. I don't have enough power to overcome gravity. I'll leave the hovering to helicopter pilots.

  10. #90
    hotrod180's Avatar
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    Sometimes prop blast can be a substitute for airspeed re lift.
    Witness raising the tail before beginning the takeoff roll.
    Cessna Skywagon-- accept no substitute!

  11. #91

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    Quote Originally Posted by hotrod180 View Post
    Sometimes prop blast can be a substitute for airspeed re lift.
    Witness raising the tail before beginning the takeoff roll.
    But is that really lift or just the control surface reaction to the prop blast against the underside.
    Remember, These are the Good old Days!

  12. #92

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    That would be a very good example of reaction lift.
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  13. #93
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    Quote Originally Posted by hotrod180 View Post
    Sometimes prop blast can be a substitute for airspeed re lift.
    But while hanging onto the prop it mostly blows the tail back down as it looses down force from lack of airspeed

    Glenn
    "Optimism is going after Moby Dick in a rowboat and taking the tartar sauce with you!"

  14. #94
    skukum12's Avatar
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    Speaking of reaction lift, here is another hair to split: How much influence does the ascending prop blade have on the underside of the wing vs the descending blade?
    "Always looking up"

  15. #95
    Eddie Foy's Avatar
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    Yes

    Quote Originally Posted by Dave Calkins View Post
    Eddie.



    Have you flown a slatted airplane? I had asked you that several times. Thanks.
    "Put out my hand and touched the face of God!"
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  16. #96
    Cubus Maximus's Avatar
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    This is probably drifting, but thinking about hanging on the prop: the Shin Meiwa US-1A https://en.wikipedia.org/wiki/Shin_Meiwa_US-1A had some interesting techniques to blow air over the wing with props, slats and auxiliary turbine and get flying "artificially" slow.





    "...The aircraft was able to land in seas up to 3 metres (9.8 ft) in height. Water distance for takeoff or landing with 79,400 pounds (36,000 kg) aircraft weight was 720 feet (220 m) with no wind or 500 feet (150 m) into a 15-knot wind.[1] Apart from the boundary layer control system (powered by an independent gas turbine carried in the fuselage), the aircraft had a number of other innovative features, including a system to suppress spray during water handling,[1] and directing the propwash from the aircraft's four turboprop engines over its wings to create yet more lift."

    http://www.airvectors.net/avps1.html
    "...The PS-1 was powered by four General Electric T64-IHI-10 turboprop engines providing 2,280 kW (3,060 SHP) each, built under license by Ishikawajima-Harima Heavy Industries (IHI), mounted on a high-set wing. Each engine drove a three-blade reversible-pitch Hamilton Standard propeller. As with the UF-XS test aircraft, a GE T58 turboshaft engine, also built by IHI, was mounted in the upper center of the fuselage to drive a BLC system for improved STOL performance. In addition, the T58 could be used as an auxiliary power unit (APU). STOL capability was further enhanced by leading-edge slats on the outboard sections of the wings and the tailplane, as well as overwing spoilers and large flaps. Take-off speed was about 90 KPH (55 MPH)."






  17. #97
    cubdriver2's Avatar
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    One would think that after almost 100 years of playing with these same ideas we would be better at doing this?

    https://en.wikipedia.org/wiki/Handley_Page_Gugnunc

    https://en.wikipedia.org/wiki/Curtiss_Tanager


    Glenn
    Last edited by cubdriver2; 06-02-2017 at 02:23 PM.
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  18. #98
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    As for the discussion, at the slight (or slightest) introduction of aileron input, mostly do to wing geometry, flow rapidly creeps out the lower surface, increasing energy in the wing tip vorticity,, which suck upper flow outwards, and further impacting Di; staling the wing very quickly. I still believe that it would have been very improbable to recover with out a substantial amount of immediate energy to get flow back on the wing. Considering the impact of Di, I'm of the opinion that while yes, the slated wings behave very well, and yes, ruder input is the correct means to get them flying... you also needed a substantial and immediate amount of thrust as this altitude. I also had the same issue testing my slated wing, wing dropped at high AoA when I touched controls. I too lost my wings and bent some tubing (testing on my breezy/cub hybrid test bed.) Not that I'm comparing skills of flying, but I did test both my limits, the wings; and made a serious mistake, but learned a lot from it.

    @Dave, exactly my point, I believe that you are not seeing a wing in flight (RC models), but rather a wing in drag. To proof the point, look up WIG airplane efficiencies, you will see the Power/Weight requirement is much higher than conventional aircrafts, since the drag is so high for these configurations (No coincidence since AR is low.) Slowest of flight is a fine balance where Cl and weight dance around Drag/Weight and Power/Weight ratios.

    However, we still need understand what happens with high AoA. As you increase alpha on the wing, you are proportionally increasing Di (induce drag), so you now need "A lot" more thrust to move the same mass of air over the wing. In other words, at this scale, as you mention the power to wight ratio is even higher, unless you can move a prop large enough (think ultra light helicopters to put into perspective) then you are basically not going to be able to scale an airplane partially by limitations in technology to make it fly like an RC airplane.

    Back to my comments and my understanding, Bernoulli's is important to explain the flow, in fact, it's the down wash, or Newtons Third Law that makes lift happen. In other words, the displacement of air mass generated by the vorticity effect of on the wing (rotation) and it's impact on the near and far field that push the wings upwards. In the far field, you are getting the upwards push, by displaying air mass onwards to the entire airmass around the airplane, generating base from which to push off (sort of speak.) Have you seen the image of the Boing flying over the clouds with vortices in the cloud behind it??? Think of that as a visual. On the near field, it's the ground plane that generates this base (same principles as those bright little perl bright water drops that momentarily don't integrate into a body of water and float around in a fusion go air on the surface tension.) In a WIG, you are in near field effect, h/c ratios are important, and relatively low. In the case of the video, one is close to, but not entirely flying on that basis.

    Off to bed now...

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  19. #99
    CamTom12's Avatar
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    Quote Originally Posted by SpainCub View Post
    Back to my comments and my understanding, Bernoulli's is important to explain the flow, in fact, it's the down wash, or Newtons Third Law that makes lift happen.
    I don't know if that's considered "in fact" or just one of the likely theories to explain lift.

    There's also the argument that the pressure differential (caused by longer/shorter flow paths) is what makes lift happen, and the sheet vortex creation and path are byproducts of creating that pressure differential. Magnus effect is an example of this, but caused by different things than airfoil shape/aoa.

    I don't disagree with the rest of your comment, but to my knowledge lift is still a phenomenon that has multiple likely theories that haven't been ruled out. Be careful making definitive statements.

  20. #100
    mvivion's Avatar
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    Quote Originally Posted by CamTom12 View Post
    I don't know if that's considered "in fact" or just one of the likely theories to explain lift.

    There's also the argument that the pressure differential (caused by longer/shorter flow paths) is what makes lift happen, and the sheet vortex creation and path are byproducts of creating that pressure differential. Magnus effect is an example of this, but caused by different things than airfoil shape/aoa.

    I don't disagree with the rest of your comment, but to my knowledge lift is still a phenomenon that has multiple likely theories that haven't been ruled out. Be careful making definitive statements.
    Oh, boy.....here we go! Actually, I think the definitive answer to the question of what mechanism actually causes a wing to create lift is magic....pure magic. It certainly simplifies the discussions.

    MTV

  21. #101
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    The mathematical prize for completing the Napier-Stokes partial differential equations is still outstanding. The Russkies have preferred Kuta-Zhukowski circulation theory, which I believe 'parks' the physics (Bernoulli, Newton, take your pick) to arrive at a more elegant mathematical approach.

    For my part I go for the Hoover, vacuum theory of lift!


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  22. #102
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    Stokes Law and Greens theorem....just triggered some calculus 4 PTSD, where is my support animal.


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  23. #103
    Cub Special Ed's Avatar
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    Wow. Way over my head. I thought it only took one thing to make a plane fly? $$MONEY$$. When debt exceeds income, then plane wont fly.
    "There are 3 kinds of men. The one that learns by reading. The few who learn by observation. The rest of them have to pee on the electric fence for themselves." Will Rogers

  24. #104
    Eddie Foy's Avatar
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    Every time I hauled back on the yoke and a 300,000 lb jet left the ground, I knew there was a God!


    Quote Originally Posted by mvivion View Post
    Oh, boy.....here we go! Actually, I think the definitive answer to the question of what mechanism actually causes a wing to create lift is magic....pure magic. It certainly simplifies the discussions.

    MTV
    "Put out my hand and touched the face of God!"
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  25. #105
    Dave Calkins's Avatar
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    Quote Originally Posted by OLDCROWE View Post
    Dave, from sailing in days gone by I understand relative wind and from that a couple of questions and observations.

    When the realitive wind is vectored down does it attach and stay attached to the bottom of the wing making for an appearent wind lift vector or is it deflected away leaving the bottom of the wing as a turbulent zone. I was fortunate to meet and fly with Wayne in the prototype for a few days and was amazed watching the slats come on and off and saw part of his string study video and remember the tops of the wing but not the bottom, or did he care?

    With fast boats tuned sails can work at very high angles of attack (close to the wind, say 35 degrees off) but you can't start with that high of an angle of attack, you have to round up to it with attached flow over the top as the realitive wind angle swings forward (reverse of powering downwind on a broad reach for amayzing speeds. When going up wind with a Jib if you loose the attached flow over the chord it immiediately back winds and you're toast in short order. The confusing part here to me is a high performance boat will point higher into the wind without a jib than with but the speed rally falls off, so it would seem to my pea brain that the slats are not truly generating lift as an extension of the wing like a jib does both with attached flow and with slot flow but floating slats are rather forcing more air along the top chord to stay attached to the wing via the slot only. So if that's the case I can absolutely see why the stall would be so very abrupt.

    Does this make any sense at all?

    Kirby
    Kirby. Close to the wind is a low AOA situation. Right? I sail, most recently a kitesurfer, with fast catamaran, planing dinghy, windsurfer and iceboat experience. The cream of the crop is the hydrofoil kitesurfboard in my opinion. Iceboats are a distant second favorite with amazing off the wind performace. Relative wind is very interesting in iceboats, yes??!! I am not a keelboat sailor.

    As to reaction lift. Simply, pick a sheet of plywood off the stack at the jobsite in a fresh breeze. There is a force on the plywood, even in a " stalled" condition, yes? Angle the plywood a bit and it will lift itself, theory be damned, yes? "Stall" be damned! That is reaction lift in simple analogy.

    lotsa smart guys reading our words. Hopefully some day they will quantify these actions or at least get to experience what horsepower, high AOA, and skill are capable of,.................if they desire to and can afford to, or have acquantances who trust them to fly their babies, THE hotrod and slatted Cubs.

    I have been blessed with the first and the last of the three (desire, and trust of acquantances, who allowed me to wring out their airplanes). Thank You Ron Kakeldey, Mike Olson/Eddie Doyle, Josh Peppard, Marc and Matthew McKenna, Art Mathias, Jim Protsman, and Bob Breeden. Thank You Wayne Mackey and Jerry Burr for the conversations, correction, and fine tuning of the mechanics and theory involved. Others who have been left out, please PM me, I will edit this list to add you gladly.

    back on topic..........rudder! Woulda helped, probably cured the Talkeetna thing. In my opinion.

    I hate discussing this without Tom's participation, by the way!
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  26. #106

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    If you want to fly slow, or even backwards, do it at altitude. I have done it many times in my cubs, and usually at 2 to 3 thousand feet. It's fun to fly backwards over the lake or the house. But you have room to recover if it quits flying.
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  27. #107

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    Doing crane work, I'm always amazed at the number of times I need to explain to the tag line dummy, that all other things being equal, UPWIND is the place to put the tag line! Ever try pushing on a rope? Back in my construction days, I often out worked much bigger but non pilot guys, when sheeting a roof in a strong wind. They fought it, this old hang glider pilot made it do the work. Just another advantage we have, being pilots, one of many of course.

    Anyone else flying vg'd or slatted ever notice that a very gradual approach to max AOA play works better then more abrupt? I think of it as giving the air a little time to realize what you are trying to do....or maybe it's just an illusion, but a very gradual approach sure seems to give me my best possible ( slowest/ highest AOA) flight.

    And what about upslope ground effect? I could swear my slowest ever (airspeed wise) are on very steep upslopes, my theory is you can fly at your usual flat ground max AOA, plus a percentage.of the hill slope. Yielding ridiculous AOA's and resultant very slow touchdown speeds and super short landings ( before taking into account the reduced rollout due to the grade), I'm talking slower then normal touchdown speeds. Talking Mile Hi and steeper type sites now, flatlanders need not respond, not that there's anything wrong with landing on level ground.
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  28. #108
    www.SkupTech.com mike mcs repair's Avatar
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    so what was the postmortem on damage to it?

    if those are the same backcountry wings as on stewarts, they don't have brace wires inside, but use 1"? square tube, that I assume is not going to be forgiving. Or adjustable after whacking wings....

  29. #109
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    Hi Dave,


    Love the way your cub mind works! I have been chewing on the reaction lift thing a bunch, and will probably have to chew on it a whole bunch more before I can make anything meaningful out of it. Courrier put it in terms I get (being a half pint framer for 25 years, I totally get the plywood thing), it just completely goes against my theory for what you after experiencing…


    I will share my thoughts, as they relate to the subject and plane in question, and you can comment or laugh at them as you please


    As you know, we can already take a cub type with good angles, lighten it up enough, give it enough power (to swing a long enough prop) and with enough wing (not talking length) we can literally rotate out of the stall and fly. Building these planes today is very doable, I know of more than one example that will do it (not all the cool airplanes in the world are in Alaska’s mainstream STOL world) . And when built like this, I don’t say you’re using reaction lift, I say you have built an outdoor wind tunnel, or… stationary winged helicopter… take your pick, the net result is pretty much the same. I submit that you are not reacting of reflexing anything, you are just blowing enough air over enough wing with the prop to get it almost flying, add a little hanging on the prop Ala VT-22 Osprey, and voila… single digit flight is attainable… Controllable single digit flight?… well… we’re still working on that. Come to think of it, the Osprey is a great example of what I think is going on, it’s just achieving it with massive steroids in the horsepower and propellor department.


    Building the airplane / wing that will do this is not the hard part. Building the tail that will keep up with this wing is! Several years ago the topic of tail authority came up, and I threw out the idea of slatting / slotting the tail to keep up with what we are doing with wings today. It was just something I quickly blurted out, and it was equally quickly poo-poo’d… so I took my toys home and elected to keep my mouth shut and thoughts to myself. But here we are again… I can assure you, you’d see much shorter numbers at these events if we could just figure out how to get the tail up to speed with the wing. I believe if we are energizing the wing with the propellor (and I believe we are) then why can’t we (better) energize the tail with the prop as well?


    At the end of the day most profound message this video sends to me has nothing to do with the aircraft capability, nor the pilots skill level. What it sends to me is what I’ve believed all along…


    Many if not most people flying slats or slots believe they have just discovered the safest airplane ever… I say hooey… Sure, if you’re going to continue to fly 55 mph on short final with you’re new Hot rod backcountry tundra 7th revision boondocker, it’s is probably going to be less inclined to bite than your old Piper Supercub. But it’s still just a wing. It has a critical AOA just like any other, it’s just much steeper than what the average cub dude is used to. Consequently, said average cub dude thinks he has an ultra safe unstallable airplane. As more and more people get comfortable with the steeper sight picture, we will see more proportionate numbers of slatted slotted wings falling out of the sky. Yes I am aware of how easy they are to get back to flying when mildly upset, but I wonder what will happen as we see airplanes capable of slower and slower speeds quit flying. I mean, you need your tail to get thing back in order. If you’ve gotten past the point tail authority, it’s going to burn through some altitude to liven it up again… slatted plane auger in? Sure they can….


    Anyways… thanks for the mind stim.


    Take care, Rob

  30. #110
    Dave Calkins's Avatar
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    It is off topic Rob, but have you given thought to a very aft empty weight CG and a LIFTING horizontal stab?
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  31. #111
    www.SkupTech.com mike mcs repair's Avatar
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    Quote Originally Posted by Dave Calkins View Post
    It is off topic Rob, but have you given thought to a very aft empty weight CG and a LIFTING horizontal stab?
    I still think a couple electric fans back in tail..... pretty powerful, reversible, all this drone stuff .....

  32. #112
    Farmboy's Avatar
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    Quote Originally Posted by mike mcs repair View Post
    I still think a couple electric fans back in tail..... pretty powerful, reversible, all this drone stuff .....
    Rutan was apparently using this idea with large electric RC motors on his latest amphib to steer while docking and such in windy conditions.

  33. #113
    skywagon8a's Avatar
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    Quote Originally Posted by Rob View Post
    Building the airplane / wing that will do this is not the hard part. Building the tail that will keep up with this wing is! Several years ago the topic of tail authority came up, and I threw out the idea of slatting / slotting the tail to keep up with what we are doing with wings today. It was just something I quickly blurted out, and it was equally quickly poo-poo’d… so I took my toys home and elected to keep my mouth shut and thoughts to myself. But here we are again… I can assure you, you’d see much shorter numbers at these events if we could just figure out how to get the tail up to speed with the wing. I believe if we are energizing the wing with the propeller (and I believe we are) then why can’t we (better) energize the tail with the prop as well?
    Rob,
    I get it, increasing the authority at the new ultra low speeds is important. In the case of this accident video I did not see either the rudder nor the elevators displaced enough for them to run out of authority by way of a control surface stall. If at any point they were at a maximum deflection then yes they would have needed some help. In lieu of the slat idea of yours, why not just increase the aspect ratio of both the rudder and elevators by adding some length? That is how it was done on the Helio. It would also work in both directions whereas a slat would only work in one.
    N1PA
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  34. #114

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    Quote Originally Posted by Dave Calkins View Post
    It is off topic Rob, but have you given thought to a very aft empty weight CG and a LIFTING horizontal stab?
    What he said- I don't know much about it, but we decided that downthrust in the engine mount was adding to the workload of the wing, and removed it- what would happen in Daves lifting tail scenario? Is it impossible to achieve the same stability with the center of lift ahead of the CG? Are the stalls unrecoverable? Something I've always wondered about. Someone knows; there's got to be a reason it's not done...

  35. #115
    mvivion's Avatar
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    Quote Originally Posted by ak49flyer View Post
    What he said- I don't know much about it, but we decided that downthrust in the engine mount was adding to the workload of the wing, and removed it- what would happen in Daves lifting tail scenario? Is it impossible to achieve the same stability with the center of lift ahead of the CG? Are the stalls unrecoverable? Something I've always wondered about. Someone knows; there's got to be a reason it's not done...
    It is done, on the latest generation fighter aircraft. Of course, they're flown by a computer, and the pilot directs the computer.

    MTV

  36. #116

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    Don't Cessna Caravans use lifting tails? I've been told that's problematic in icing conditions, but all that's over my head. I just want a plane that gets me where I want to go. Sometimes that's my Cessna. Coming soon my Cub. Sometimes a 777. Life is an adventure.

  37. #117
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    Dave et al,

    My apologies for the thread drift... I do think the slat conversation is relevant, as many slat / slot drivers truly believe their planes are invincible. Which IMNSHO is why this thread exists. The driver in the video clearly fit that bill.

    Quote Originally Posted by Dave Calkins View Post
    It is off topic Rob, but have you given thought to a very aft empty weight CG and a LIFTING horizontal stab?
    Yes, and thank you for reminding me to revisit this. Someone once started a thread exploring the possibility of adding a canard to a cub. In my mind, your proposition is an easier (on a cub) and more elegant solution to achieve essentially the same effect.
    I scrapped the idea, because the failure mode scared the begeezuss out of me, although I admittedly have no education or experience to base that fear on other than being in an airplane (C180) with a runaway trim, an ag plane with an inadvertent dump, and another agplane with the stick pinned in a steep climbing left turn.. In all cases the runaway climb gave me pause (to say the least). At the end of the day, failure is failure I guess, and maybe up or down is irrelevant? But even a true Canard retains a 'down flying' tail...Thoughts?


    Hi Pete,
    Yes! long live long wings I love the free ride long wings (increased aspect ratio) offer... I use them on everything I fly. At the end of the day, since I am of the opinion that cubs of this caliber are flying on the prop wash, it probably isn't a stretch to imagine that we could stretch either wing (main or tail) to the moon, and we soon reach the point of diminishing returns. On planes of this caliber the tail needs more than extra chord or aspect ratio. Extra chord has been done, even exists via STC... it works great! But you need more than single digit airspeeds to reap any benefit.... Beyond that there has even been airfoil improvements, but alas they still don't hold a candle to how much improvement has been done to the wing of these cubs... I mean really? We fix the angles, add slats or slots, VG's, clean everything up and then what? throw the tail a bone and give it 3 inches of chord? Ha.... not enough.... Maybe tail rotor ? Thanks Mike! I never would have thought of that! It sounds very doable!

    Back at Dave, Ak49, and Pete,
    Tail... yes, being able to stall the wing of these uber cubs would be great, but that isn't even half of the problem. What we really need is a rudder that will work at single digit speeds. Because regardless of where this poor guys feet where when they should have been moving, I am of the belief that even with his rudder pinned to the stops, he was not going to salvage that spin. He was for all intents and purposes, a passenger once she broke. The solutions offered for the elevator are good (although I don't believe enough) but what about the rudder? because in the end, that's going to be the deal breaker. As I pointed out we can currently rotate at almost no ground speed and fly, why doesn't anyone do it in competition? because at that point they have no control over p factor, torque, or even a little gust. That, is where the next big improvement needs to be.

    Stu,
    Amen brother, so far I agree with everything you've said in this thread, which is is why a PIC (politically incorrect) person like me wouldn't touch the OP with a ten foot pole.... but now I guess I'll bite... I could write a small novel on exactly why the person in question does NOT appear to be a good stick, and almost none of it would be about rudder control... but that would not be very unpopular and at the end of the day, would an entire opinion formed on a 20 second snippet of someones performance under duress really be cool? I mean, not that I have ever made a mistake or anything..... Ha!

    I assure you I can teach an orangutang pretty much all it needs to know about flying an airplane as slow as it will go... Slow flight is not IMHO any measure of how good a pilot anyone is. What is going to happen when it goes too slow, how and if it is even possible to fix that at low altitudes, what the rest of the day entails if everything goes sideways, and what those consequences are going to do to everyone around you that day, and the choices you make regarding these facets, are far more a measure of how good a stick someone really is to me, than how slow their airplane is traveling at any given moment. Anyone can slow it down to the point of breaking.... Anyone... even an orangutang

    Slow flight contest at 100' AGL?.... really? who was dumber on that one? the participating pilots or the one who dreamt up the idea knowing full well that someone was going to wreck... This was a foreseeable albeit unfortunate event. I would have bet my entire years earning that someone would have wrecked on that day...
    I love nascar, and almost every race someone is going to wreck, we know it, they (drivers) know it, and a tremendous amount of thought and planning goes into that aspect of the race. I wonder how many participants at this display of "skill and talent" planned on wrecking?... oh yeah... none, instead we went the pity party route when things went sour... bummer... all who know me, know that I would be the first to help you pull wings and move a plane, first to drink a few while we pass the needle stitching ribs, or hold the new wings up while we re rig and reinstall... but Go Fund Me? Really? Man, if you can't own up to it, you shouldn't be doin it.... Let that one go for the grieving widow or mom who has no idea how to pay for the burial of her untimely loss, or for the mom and pops outfit, whose home and business burned to the ground... If this gentleman is anything like me, (and I suspect he is) he built this cub on his own just fine, and he will rebuild it on his own equally as fine.

    Take care, Rob
    Last edited by Rob; 06-06-2017 at 08:07 AM. Reason: grammar
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  38. #118
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    Quote Originally Posted by Rob View Post
    Slow flight contest at 100' AGL?.... really? who was dumber on that one? the participating pilots or the one who dreamt up the idea knowing full well that someone was going to wreck... This was a foreseeable albeit unfortunate event. I would have bet my entire years earning that someone would have wrecked on that day...
    I love nascar, and almost every race someone is going to wreck, we know it, they (drivers) know it, and a tremendous amount of thought and planning goes into that aspect of the race. I wonder how many participants at this display of "skill and talent" planned on wrecking?... oh yeah... none, instead we went the pity party route when things went sour... bummer... all who know me, know that I would be the first to help you pull wings and move a plane, first to drink a few while we pass the needle stitching ribs, or hold the new wings up while we re rig and reinstall... but Go Fund Me? Really? Man, if you can't own up to it, you shouldn't be doin it.... Let that one go for the grieving widow or mom who has no idea how to pay for the burial of her untimely loss, or for the mom and pops outfit, whose home and business burned to the ground... If this gentleman is anything like me, (and I suspect he is) he built this cub on his own just fine, and he will rebuild it on his own equally as fine.

    Take care, Rob
    Well said, Rob. I couldn't agree more.....a slow flight contest at low level??? Really?

    MTV
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  39. #119
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    One of the biggest take-aways from this event is probably that people have to fully understand social media, and the public's reaction to it.

    A few theories out there about "the who" and "the why" the gofundme was started for the pilot, and it's advertising, promotional and facetime value. But at the end of the day, one has to step back and realize that the PILOT/OWNER did NOT start the gofundme, and as I understand, would not have done so personally.

    Sadly, to help out others publicly these days, you have to consider public backlash at your methods. I'm all about helping a guy out, but the gofundme was a bad choice (in my opinion).

    Often it's best to simply go over and give him a hand in person.

    pb
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    In perusing the list of donors, I found Cub Crafters had chipped in. Where is Back Country? I suppose changing one word in an old saying may apply here: "AVIATION makes strange bedfellows."
    "Always looking up"
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