Retractable Gear question

[Wayne Hicks]

The nagging voice in my head says to sit back and watch. But I'll play:

 

(1) Lack of initiative? Are you saying the canard crowd LACKS initiative? This canard crowd is the very definition of initiative, development, experimentation! The canard builders arguably take more initiative with mods to their planes than any others. Just because the initiative hasn't quite spread yet to even ONE completed steerable nose wheel, don't throw the baby out with the bath water. This isn’t the first time SNG has been discussed. And it won’t be the last. I have three concepts of my own. But I prefer the castor.

 

(2) What's so necessary about the SNG that the whole fleet should have one? It may be necessary to you, and you may have you own unique desires to build one. But that doesn't make it necessary to everyone and there’s no need to get upset that not everyone shares your vision. Is it a good idea? Uhm, there are pros and cons. Is it practical? Uhm, there isn't one yet in the field. To me that's a good clue, or at least an initial point of reference for what the fleet thinks about it. The canard fleet is VERY QUICK to implement necessary mods. Most are safety and speed oriented.

 

(3) I don't see retracts flying off the shelf. And I promise you JD isn't making RGs and SNGs to get rich. He's doing it fill a niche market. A very small one at that. JD has been working on concepts and prototypes for a long time now. If demand were that high and the profit margins could be realized, I bet he'd redouble his efforts to complete them. Alot of us would like to see them come to fruition. It’s good for the breed. We all wish him luck. But in the mean time, most all of us will not sit around waiting with our fingers crossed. We have planes to build and fly.

 

(4) I haven't done alot of high cross wind takeoffs, but I don't recall ever using excessive braking to control direction on takeoffs. I don't recall having to roll extensively longer because of it. I use the scallop approach to crosswind takeoffs. Point the nose downwind of the centerline. Nail the throttle, time it just right for the wind to swing you back to the centerline in time for the rudders to take effect. Works every time. I might tap the brakes twice in all this. Do you have any castor time? It's not like you stand on one brake and hold it down you know.

 

(5) Sorry, but the experimental industry is thriving because you can build a $50,000 airplane from a kit that out-performs a $400,000 factory-built plane. It's not thriving because of $$$ made just on ingenuity alone. And the last time I looked, the Cozy and the Long-EZ are nearly identical, save for the extra 22 inches in the fuselage and thicker spar caps.

 

(6) Look….no one is saying SNG can't be done. Marc is just telling you in his own unique way what others already know, have experienced, or have simply taken for granted. It’s hard for many of us to fathom an SNG being simpler and lighter than castoring, especially what we have now. I say, "Go for it!" You have that right. I'll sit over here and watch. I'll clap the loudest when you're done. I'll be happy to participate if you desire some peer review, which is one of the purposes of this forum. But when you ask for peer review, you're going to get both sides of the story. Fair enough? So when someone like Marc or myself gives thumbs-down opinion to the realistic practicality of SNG, we’re answering that aspect and that aspect alone. We’re not telling you not to design and implement it. Nor are we shooting down your right to do so. I for one think it would be a cool accomplishment, but nothing more substantial than that. Others may feel differently?

[Marc Zeitlin]

J... Guys like Marc have there place in this world. We need the nay sayers to keep the fires lit. God knows without guys like Marc we surely wouldn't be flying airplnes right now, the Wrights Bro.s would've just given up.

Actually, the Wright's were far closer philosophically to my position than to yours. They studied the existing theories, developed their own, tested everything they developed, and attempted to come up with the best, most efficient solution they could using the technology available to them at the time. They did nothing just so that they could be "different". They were engineers in the best sense of the word - they were NOT laymen, by any stretch.

 

With respect to your nosegear, as soon as you have it built, mounted on your airplane, weighed, and tested to 120 mph on the ground, and it weighs less and works better than a castoring nose gear, I'll be happy to state publicly that you've come up with a better mousetrap. Until that time, it's hardly reasonable to state that your two drawings are an example of working steerable nosegear for a flying canard aircraft, any more than it's reasonable for Infinity to state it for their design. There are over 2000 examples of working castoring nose gear on canards - I was looking for ONE example of working steerable nosegear on canards. Can you point me to ONE?

 

With respect to your attempted insults, I have almost never said "it can't be done". Almost ANYTHING can be done - the only things that can't are those that defy the laws of physics, which steerable nose gear certainly doesn't - the question is whether it's useful, reasonable, economical, or smart to do so. I was merely addressing airwrenches astonishment, when you stepped in with your insults and objections to reality.

 

You haven't addressed the issue as to why Cirrus etc. have gone the castoring route. Are they all stupid, Luddite, anachronistic, neanderthal naysayers like me, too?

 

I suppose I got my current job just so that Scaled could say that they had one idiot working for them - kind of an equal opportunity thing going on.

[tonyslongez]

Actually, the Wright's were far closer philosophically to my position than to yours. They studied the existing theories, developed their own, tested everything they developed, and attempted to come up with the best, most efficient solution they could using the technology available to them at the time. They did nothing just so that they could be "different". They were engineers in the best sense of the word - they were NOT laymen, by any stretch.

Why is this any different than trying to develop a steerable nosegear. I've studied the existing nosegears quite thoroughly. I've developed my own, I intend on testing everything I'm developing. I'm attempting to use the technology that is available to me at this time. I'm not doing this to be different and what is wrong with being different? We fly canards don't we. How different is Burt? Very different. I feel like I'm an engineer in the best sense of the word. What makes you think the people you are addressing are laymen.? This is an open forum you know, or are you the only engineer in the world?

 

 

With respect to your nosegear, as soon as you have it built, mounted on your airplane, weighed, and tested to 120 mph on the ground

Why do I need to steer at 120mph I'm sure you insisted that there would be no need to steer our aircraft after 40mph because our rudders where sufficient for steering so which is it engineer? 120 or 40:confused:

it weighs less and works better than a castoring nose gear, I'll be happy to state publicly that you've come up with a better mousetrap.

Weighs less? No probably not. Weigh a little more? yes. Work better? maybe wouldn't know that until I get it finished. I don't need your statements Marc I've had enough of your statements and negativity for a few days. I could care less what you think of my mousetrap.

 

With respect to your attempted insults, I have almost never said "it can't be done". Almost ANYTHING can be done - the only things that can't are those that defy the laws of physics, which steerable nose gear certainly doesn't - the question is whether it's useful, reasonable, economical, or smart to do so. I was merely addressing airwrenches astonishment, when you stepped in with your insults and objections to reality.

Insults? hardly! " I have almost never said it can't be done" That's really funny. You never said it could be done either. I'm sure you meant the laws of physics as we know them. Well it's interesting that you bring up 2000 examples of castering nose gear for canards and yet there is 1000's more examples of steerable nose gears on other aircraft. It doesn't know it's not on a canard. We have over 450 aircraft in our fleet all of which have steerable nose gear which B.T.W. turn on a dime. For the sake of this very interesting discussion. Which, I still haven't gotten anything out of, with the exemption of "it can't or shouldn't be done". I will yield the balance of my time to further discuss this after the gear is finished. Untill then I'll go back to building my airplane and proving you wrong.

 

Mr Hicks

 

No sir I wasn't implying that we canardians lack initiative. I agree with your post. for the most part. I just don't have alot of time just now to respond properly. Just know, that your posts are far more constructive than some that I have seen Marc post and not just on this topic. His suggestions however relavant they are, don't come across his posts as constructive, at least not for me. All I was asking for initially was some feedback on the drawings if anyone can see something I overlooked that's all. I don't care whether it should or shouldn't be done it's going to be done so how do WE make it better? what I was looking for was, that looks like a good design, or bad. If bad, why? what about if you did this, instead, that would eliminate this. Or! that looks good try this. Not all this other happy HorseSh*$ I got in response. Good LORD!

 

Tony

[airwrench]

Why is it astonishing that no one has "addressed" an issue that doesn't need addressing? Infinity has been threatening nosegear steering in their canard for over 10 years, but that's gone nowhere. If there are any canards out there that have installed nosegear steering, no one I've ever talked to has ever seen one. There's a reason for that - it's like trying to exterminate all the giraffes in Alaska - it's really not a big problem that needs addressing.

 

Have you ever flown an aircraft with differential braking, like a L.E., V.E., COZY, Katana, Cirrus, Lancair Columbia or a Grumman Tiger? It's pretty simple. I can spin my airplane in it's own length - try that with nosewheel steering. The ONLY issue with differential braking is taxiing (and the early part of a takeoff run) with a strong crosswind, but there are relatively simple techniques for dealing with both of those.

 

I don't know what airplanes you rent, but if you think that you can do any amount of steering at 90 mph using the nosegear, rather than the rudders, you're fooling yourself. The COZY rudders kick in at about 40 mph, and differential braking (or simultaneous braking, as the case may be) works at ANY speed.

agreed, and 90 was when I wanted command authority to steering,lol, in a canard we are in the air @90........

[Marc Zeitlin]

.... What makes you think the people you are addressing are laymen.? This is an open forum you know, or are you the only engineer in the world?

Most folks are not engineers (either school taught, or self-learned). The safe assumption to make is that the folks we're addressing are laymen.

 

Why do I need to steer at 120mph I'm sure you insisted that there would be no need to steer our aircraft after 40mph because our rudders where sufficient for steering so which is it engineer? 120 or 40

YOU will need to steer at 120, because YOU will have nosewheel steering on your plane, and YOU will touch down at 120 mph GS every once in a while. _I_ will only have to steer with something other than the rudders below 40 mph, although I have the capability of doing so with the brakes as well. If YOU attempt to steer with the brakes at your 120 mph touchdown speed, you will put a very large side force on the nose gear. If you put in springs that allow castoring with any substantial amount of force on the nose gear, then you will have defeated your nosegear steering purpose.

 

Maybe you should think these things through before throwing the insults around when someone points out facts to you.

 

All I was asking for initially was some feedback on the drawings...... Not all this other happy HorseSh*$ I got in response. Good LORD!

So, someone other than you (cybersushi) starts this thread. Then, someone other than you (airwrench) posts a statement to which I responded, saying NOTHING about your particular design. You then take it upon yourself to assume ownership of the thread, as if no one else has a right to respond on it unless they get your approval, and you think that it's YOU that are getting happy horseshit?

 

You don't know the history of the design you're building, you don't know what modifications have been attempted and/or discarded by other folks before you or why, you think that you're the only one that has the ability or drive to complete this particular modification, you admit that you insult me without knowing MY history, you DON'T address the valid issue of other aircraft that have castoring nosegear, and you think that I'M full of myself?

 

At least I realize that I don't own this forum or thread, not to mention drive, ambition, and capability, and that everyone has a right to have their say, whatever it might be.

 

Listen, Tony. You're obviously a bright guy, and you're attempting some pretty interesting stuff with your airplane, even if a lot of the changes seem to be for the sake of change alone. But I hope you succeed, because it would be cool if you do. However, jumping down people's throats and insulting them because they write stuff you don't want to read isn't going to help you any.

[tonyslongez]

Listen, Tony. You're obviously a bright guy, and you're attempting some pretty interesting stuff with your airplane, even if a lot of the changes seem to be for the sake of change alone. But I hope you succeed, because it would be cool if you do. However, jumping down people's throats and insulting them because they write stuff you don't want to read isn't going to help you any.

Marc i'm not going to even respond to that other stuff. I apologize for jumping down your throat and insulting you. In the end it is going to work and work very well and I have a fealling that you and everyone else are going to be pleasantly surprized. The issue of SNG keeps coming up someone ME is going to figure it out for whatever reason nobody else wanted to. So let me just say. "I really enjoyed our banter it stimulates my design ability". trust me when I say that I paid attention to what you posted though I may not agree with it, it did not fall on deaf eyes. I'll see you at Oshkosh.

 

I'm not sure where you got 120mph though. can you help me with those numbers?

 

Tony

[Marc Zeitlin]

..... I apologize for jumping down your throat and insulting you..... I'll see you at Oshkosh.

Accepted, and if I made you feel that I was attacking you with my responses, I am also sorry - that was not my intention. I'll be happy to discuss this with you in person at OSH, if you like.

 

I'm not sure where you got 120mph though. can you help me with those numbers?

Sure. Let's say that you're either taking off or landing at a high density altitude airport, and you're relatively heavy. Your IAS on final may still be 90 - 100 mph, but at 6685 ft. altitude, on a hot day (say, at Durango, CO in the summer, like when I landed there last August with my wife, tons of baggage and full fuel), the density altitude will push 10K ft. That means that as you touch down (or rotate) at 100 mph IAS (which, in the COZY at gross weight and mid CG, is about the speed I needed to begin a climb), your TAS and GS, with no wind, will be about 120 mph. These speeds are realistic for LE's and COZY's - many canard drivers land even faster than this, although I'm not sure why.

 

If you have nosewheel steering coupled to the rudder pedals, then as you attempt to maintain directional control using the rudders, you'll also be adding nosewheel steering inputs. The nose gear needs to be able to handle those loads at those speeds (and all lower speeds). These forces can be substantial as velocities get higher than walking speed. If you set the castoring breakaway so that it will castor at low enough forces so that you don't overload the nose gear and attach points at these speeds, then the question becomes "what is the nosewheel steering doing for you"?

 

Make sense?

[tonyslongez]

Yes makes sense.

 

Look at the renderings do they make sense? the way I'm looking at it is the nose gear of all these canards are basic tail wheels like from a tail dragger just in the front. The tube could be Carbon fiber, fiberglass, titanium or whatever. or it could be solid like what we have now. I don't like the idea of rigging the nose gear steering to the pedals I'd rather have a tiller wheel like we have in our 737's. So at low speeds say 40knts I'm guessing here. I don't know the spring rates yet. Lets say 40knts and below, You steer with the tiller as speed increases we get light on on the nose, so now we are into rudder steering is that right?

 

My thinking here is that any heavy side load could easily overcome the springs kicking the wheel over to what ever side just like a tail dragger. Your airplane is now tracking in the direction of the load as it allready does. That is if you land all cockeyed. So basically like a tail dragger you are able to steer a castering tail wheel you just can't steer past the forces of the springs. Nothing really changes in our current build up of the ng30 as I see it. It doesn't know its a steerable castering nose gear. I may even be able to use the stock caster if not I'll simply machine a new one. Also we can still use the compression washers for steering dampning, They will just be on the bottom now instead of the top.

This really is a simple thing to do.

 

Tony

[airwrench]

Accepted, and if I made you feel that I was attacking you with my responses, I am also sorry - that was not my intention. I'll be happy to discuss this with you in person at OSH, if you like.

 

Sure. Let's say that you're either taking off or landing at a high density altitude airport, and you're relatively heavy. Your IAS on final may still be 90 - 100 mph, but at 6685 ft. altitude, on a hot day (say, at Durango, CO in the summer, like when I landed there last August with my wife, tons of baggage and full fuel), the density altitude will push 10K ft. That means that as you touch down (or rotate) at 100 mph IAS (which, in the COZY at gross weight and mid CG, is about the speed I needed to begin a climb), your TAS and GS, with no wind, will be about 120 mph. These speeds are realistic for LE's and COZY's - many canard drivers land even faster than this, although I'm not sure why.

 

If you have nosewheel steering coupled to the rudder pedals, then as you attempt to maintain directional control using the rudders, you'll also be adding nosewheel steering inputs. The nose gear needs to be able to handle those loads at those speeds (and all lower speeds). These forces can be substantial as velocities get higher than walking speed. If you set the castoring breakaway so that it will castor at low enough forces so that you don't overload the nose gear and attach points at these speeds, then the question becomes "what is the nosewheel steering doing for you"?

 

Make sense?

wait a second tonyez, I am not the one casting insults or arrogance, I am all on board with you on the ability to command the steering........and for the other guy who wanted to know, yes, I do fly LARGE airplanes.

[Marc Zeitlin]

... So at low speeds say 40knts I'm guessing here. I don't know the spring rates yet. Lets say 40knts and below, You steer with the tiller as speed increases we get light on on the nose, so now we are into rudder steering is that right?

OK, so once you've decided that the steering can be overcome with large enough forces, and will only be used at relatively low speeds, what's the advantage? Any large crosswind on takeoff at low speeds will require more force than the springs can provide, and you'll be castoring. I think that you'll find that if you set the springs appropriately, you'll essentially be castoring almost all the time, and steering only at very los speeds and very low turning angles.

 

Plus, the steering can never have the throw of a castoring wheel, so your turning radius when steering will be much larger than your turning radius when castoring.

 

We're not talking about heavy iron here - it seems as though small GA aircraft are moving away from steerable nosegear to castoring nosegear. There's a good reason for that - it's lighter, simpler, and works at least as well.

 

So, yes, your system can certainly be made to work - of that I have no doubt. It will weigh a bit more, and it will be more complex, but it can do what you propose. I just don't see where any advantage is to this combined system.....

[tonyslongez]

OK, so once you've decided that the steering can be overcome with large enough forces, and will only be used at relatively low speeds, what's the advantage?

Plus, the steering can never have the throw of a castoring wheel, so your turning radius when steering will be much larger than your turning radius when castoring.

Well, the first quote took a minute. It's like I said before, just saving on simple wear and tear from dragging a break in high winds, or those long taxis at Osh. Sure you can buy lots of fifty dollar brake pads as you stated before but, honestly Marc, I don't want to tear my wheel assembly apart that many times. Heck, we are changing brake pads like mad on our 172 now, and it steers. I can't imagine what it would be like if it castered. Taxi ways and runways alike aren't always flat. They are more rounded so aren't you tracking alot when you taxi? I know I do and I'm steering with my feet(in the 172). There may be other advantages that I'm not seeing, but I think it's cool to let the consumer decide if they want a relatively light and not really that complex steering system. What's the big deal about SNG anyway? We should have that option. You agree?

 

The second quote: I'm not sure I agree with that. Have you ever taxied a 737? When you turn that tiller that nose gear can crank over to damn near ninety degrees to the fuse. It's amazing the radius this airplane can turn in. I think you can have considerably more throw with the tiller because your dealling with a rotating motion not a linear, as the case would be with pedals. Just keep cranking the wheel until you hit the stops. Or set the ratio behind the tiller to the wheel, at say, 20:1 or what ever you want it to be.

 

We're not talking about heavy iron here - it seems as though small GA aircraft are moving away from steerable nosegear to castoring nosegear. There's a good reason for that - it's lighter, simpler, and works at least as well.

No, but we are talking about old iron (GA iron that is) most, not all, have some type of steering command other than braking. Yes the caster is lighter, simpler, works as least as well. I'm O.K. with that, if you want a castering nose gear. Some people want a steerable nose gear and this is a start to giving them that. Please for my sanity, stop saying how complex it is. I mean, it really can't get any easier than what you see in the rendering. It's a couple of springs and some pulleys. I can't make it any easier than that for what it does. I remember reading in my plans for the Long, Burt did try to come up with a steerable retractable nose gear, but in the end decided it was easier to use castering. I wonder which designs he was looking at to model from initially, before he gave up trying to come up with his own design? The castering does work, but if you throw some springs on it, you can steer it as well. You have the best of both worlds. All he had to do was look at it like it was a tail wheel and not a nose gear. I'm sure he would've come to the basic design I have. I know he is smart enough.

 

Tony

[Steve Innova]

Tony,

 

I really like you're on to something with the spring / caster design you have.

 

The only thing I'm concerned about is the overall shock absorbing capability. By putting your wheel/axil out behind the strut on a separate attachment (looks about 6" long), you introduce a significant lever arm. The shock forces will act vertically and to the rear on that lever arm, instead of being transmitted up the strut/shock absorber combo. There's no damper for these forces (short of twisting the strut at it's pivot on the NG30 bulkhead at the fuselage), and it will either crack the pivot or (more likely) the axil / wheel attach bracket.

 

The reason that a Long EZ attach bracket works is that the shock forces are transmitted upward and backward along a rotational movement, aided by the strut pivot. The strut rotates backward, rather than compressing upward.

 

I think you need to redesign the axil/wheel attach bracket to put the axil directly beneath the strut, to transmit the shock up the strut. The spring/caster will still work, it just needs to extend ahead of the axil.

[Chairboy]

Tonyslongez:

 

I think the whole opposition here can be summed up thusly:

 

You're obviously a Witch, and should be burned!

 

I kid, I kid. I think we're all interested in the idea of a simple steerable nosegear, it's just that some people have some concerns about some of the implications behind it. For example, having a nosewheel that's linked to your rudder control, you land in a crosswind. You still have a little rudder input in because of the xwind when the nose gear touches down at 120mph (a boundary case, but people who only plan for normalcy never have any wiggle room when a problem happens). The LongEZ and Cozy are half as long as a Piper or Cessna, so their directional stability in this case will be lower, right? What are the implications to touching down with a wheel off-center?

 

I'd like to see this work, I just want more info.

[tonyslongez]

Steve

 

Which drawing are you referencing? I have a few up there at this point. There are a couple on page 3 of this thread which uses a shock. This particular design I was thinking, I could use a carbon tube or a fiberglass strut for shock absorbtion kinda like what we have now. It just needs to be rounder than the square nose gear strut we have. Just so everyone knows those are not scale drawings. Just shooting ideas out there as they come to me, trying to get them down on paper.

 

Tony

[tonyslongez]

Chairboy

 

I have a pile of leaves in my backyard I'll stand in the middle just hand the lighter to my wife. I'm sure you'll be more than happy to help burn the witch:D

that's really funny

 

I'll try my best to give you guys as much info as I have. Right now all I have are ideas and a machine shop. As far as I can tell nothing really changes except you can steer. We still use the same amount of shimmy dampning I'm trying to use the existing caster fork thingeee assembly. if it works now at 120mph why won't it work just because you can steer it? it doesn't know if its you giving it the input with your foot or some other external force like breaking, it just goes in what ever direction you tell it to go. I want to be clear here. I'm not sure if steering with your feet is the best way to go. I really feel strong about the tiller wheel. I believe it's possible to have close to the same turning radius we have with castering if we stick with the tiller wheel.

 

What are the implications to touching down with a wheel off-center?

Nothing really that's the beauty of it. It still casters. You have to look very close at the drawings I have on both pages of this thread. Try to picture what is happening. Look close at the steering bellhorn. If you steer with your feet and you have a cross control input during landing the fork on top of the strut is shaped in such a way that no matter what input you have the wheel is going to turn in that direction it works the same way any airplane is steered now with the rudder pedals. If you have a cross wind landing the wheel is pointed in what ever direction your foot is telling it to go. If you land nose gear first that's a crappy landing one, two the nose gear is going to kick over and so is your foot but with this design it just simply kicks over in about a half a second untill you either regain control of the landing or the force of the springs takes back over and you steer again. Any other issues you should still be on your mains untill the last possible minute then the nose falls then there is no issue. But that Mole on my crooked green nose sometimes clouds my thinking and I could be wrong on everything.

 

Tony

 

 

 

Tony

[tonyslongez]

How about something like this

 

replace the aluminum fork with a fiberglass one that also acts like a leaf spring. Sorry for not finishing the drawing but you can kinda see where the cahnges where made form the last one:rolleyes: maybe make the nose strut out of thick walled carbon fiber tube very stiff. Let the fork now made of fiberglass act like a shock just like our maines. We can still use the springs for steering we may now be moving into a lighter nose gear.

Tony

[tonyslongez]

Here are some other drawings I worked on. The bracket in the middle of the tube is for the whilhemson nose lift. I'm not sure why my Rhino isn't rendering in color. I'll try to get these in color so you can see where the bushing are then it will be easier to tell what rotates and what doesn't.

 

Tony

[Steve Innova]

2 things:

 

1: The leaf spring is, IMHO, a bad idea. It's too short and thick, and flexing will quickly crack it. Plus, you'd need to make it out of steel, which is heavy, and would be more difficult to machine.

 

2. If you want to put your wheel/axil behind the strut, then you might as well make it a true trailing link design, with a built in shock absorber in the trailing link. There's lots of ways to do this (some have even used leather disks).

 

Why don't you go with a strait strut, using a motercycle shock or oleo tube, with the axil centered beneath the strut, rather than trailing? That combo should allow enough shock absorbing capability to permit grass field operations.

[tonyslongez]

Steve

 

Did you look at the other drawings on page 3 of this thread?

 

Remeber these are not scale drawings. Parts at this stage are going to be thicker or thinner in some places. These are just concepts that I'm working on. The trailing link is O.K. but there are better ways of steering if you'll look at page 3 of this thread, you'll see my idea of getting rid of the trailing links and saving weight. The motorcycle shock is inside the tube where the spring is visible through the slot. Which is essentialy replacing the trailing link. B.T.W. the shock is a rear motorcycle shock where the swingarm is.

I'm sure everyone thinks I'm crazy but at this point, I don't see anyone else posting any ideas to work from. Which, I would love to see. This is very time conssuming. Just so you know the idea here is to try to not have to modify the ng30 or the current wheel-well position, Keep thinking we'll get it figured out

 

Tony

[athomp58]

Tony,

Your drawings are great! You are prolific! I haven't had time to get even one conceptual sketch done. Chill out a little bit. I don't want you to burn yourself out on this too quickly.

 

Here are some thoughts I've had:

1) A pneumatic strut from a motorcycle front fork may be better. (I'm thinking of your first drawing here.) The spring rate could then be adjusted with air pressure. These are light weight, made of stainless steel and aluminum, and can handle substantial bending (side) loads. Your outer tube could then be non-structural and only transmit the steering torque. One advantage to a pneumatic strut is that under extreme loading the restoring force would be non-linear and the strut would be less likely to hit the end of its travel. We would need to choose a strut with the right amount of travel or limit the travel someway. How much travel do we need? During takeoff the strut will be contributing lift to the nose. Some of you who have experimented with nose strut height need to comment.

 

2) The axle of the wheel needs to be trailing the strut (or steering) axis to achieve the castering. Your later drawings have this feature. The early Lancair nose gear had trouble with shimmy. Is anyone knowledgeable about how this was fixed?

 

3) I can't let go of the image of the trailing link gear I saw on the jet. I like the trailing link concept for a couple of reasons. It would be easy to fabricate from off-the-shelf 4130 tubing with the energy absorption and support force done with light weight, off-the-shelf pneumatic components. And, we may be able to make it fold into a small space. Imagine a truss structure with a hinge at the top and a hinge about half way to the wheel. It

would "coil up" into the wheel well and be actuated with a steel cable or small roller chain.

 

4) A question for the group: For a CozyIV, what is a reasonable range for the pre-departure nose wheel weight?

 

5) Finally, we need to open the floor for nominations for a wheel size. One of our design objectives was to have better operation on turf. It should be a readily available size with symmetric hub bearings. The feasibility of some of the above may depend on the wheel size.

 

Aubrey

[Spodman]

Glad to see the discussion more technical and a bit less personal. Don't push the SUBMIT button when you are angry.

 

I think some are a bit dismissive of the SNG concept coz many have suggested it as a bold leap forward, but nobody has delivered, including Burt:

We are also developing a new, steerable nosewheel (fork and lower casting) which will be retrofittable to both VariEzes and Long-EZs. This project is in the early stages of development, so please don't call us for information. When it is successfully developed and flight tested it will be available from Ken Brock, perhaps around Christmas time.

That would have been Chrismas 1982... Unlike others that have promised same, the admission of defeat from Burt came in the next CP:

This endeavor has been a dismal failure so far. It really is a much more complicated problem than it seemed at first. We have had several different iterations installed including two totally new nosewheel forks. None of our efforts have shown enough promise to pursue... The Long-EZ is such a simple, easy to maintain machine as it is, a change such as that suggested above, would necessarily make it more complicated and difficult, not to mention expensive to maintain.

To expect somebody who is aware of this history to embrace joyously something that hasn't flown yet is a bit naive. To expect the first thing you bolt to an aircraft to work well enough to be safe to fly is naive, but I wish you well with it and would cheerfully use it if it proves superior when you have developed it , (if your resources and interest are able to take it that far, and I hope they do).

 

To threaten disrupting a room full of people who have turned up specifically to listen to somebody because he poses some reasonable questions about your idea is infantile, offensive and deserves moderator action. Maybe its a cultural thing, but I don't get what it is about Marc's questions (on many topics) that get people's backs up.

 

The Wrights have been championed as the master innovators in this thread, but I see them as very conservative. From the first gliders to the 1911 flyer the layout is almost identical. The hideous chain drive props from the 1903 are on the 1911, despite many alternatives being proven by then. They didn't change ANYTHING until they were good and ready, and FTW. If they had built a Vari in 1975 (posthumously) it would still have elevons and a revmaster today...

[Wayne Hicks]

"(The Wrights) didn't change ANYTHING (from 1903 to 1911) until they were good and ready."

 

-----> Please remember that the Wrights basically put the Wright Flyer into an 8-year hiatus while trying to procure the patent on "the airplane".

[tonyslongez]

Here are some other drawings I've been working on. This design might be the one I go with for my Long.

The foot and strut are stationary. The steering fork on top is connected to an inner rod which goes down thru the strut out the bottom to steer the wheel. the foot would be made form aluminum and the strut might be carbon fiber. It's not perfect but it's getting there.

 

Tony

[tonyslongez]

Here are a couple more I have to look at this one some more.

 

Tony

[tonyslongez]

O.k there we go, thats better.

 

Tony