argoldman

The plane around that guy must be made of transparent aluminum.

Beam me up Scotty:)

prone position, it's interesting: it would be like to ride a motorbike......

I feel like I have more sensitivity to the bike's behaviour sitting prone than to the car's behaviour sitting reclined.

prone sitting gives you also more stability(assuming your legs have something to hold), but I'm skeptical about neck confort: I actually ride my bike for many hours with no neck problems, and we should consider the elmet's weight and wind force.

when riding on race tracks you also get some g force and I had never neck problems.

I wonder if it would be a good solution, but looking at formula1(cars) that is the highest expression of performance and g force on the ground(in europe) I see that they sit reclined and I cannot think they did not consider a different solution: they have tons of engineers and money to spend to research!

but I think the reason for this position could be merely a habit: we have always sit that way since cars exist.....

do you have some links to see those aircraft with prone sitting you talked about?

Nothing new about the prone position. Orv and Wil used it in their first. They, in fact were the first aviation hippies (using their hips to control something or other.)

We could develop a head holder or a prism system, or now with glass panel a virtual view of whats in front of us so that we wouldn't have to flex our necks.

Taking a drink or eating might get a little difficult as might breathing with increasing Gs since the rib cage will be compressed.

I guess we could get used to the rudder inputs, and just think of all of the luggage we could pile on top of ourselves. For two place, we could use bunk beds. Getting in and out would be a snap as long as there is a crane nearby. I also kinda like the idea that in a crash my head would be the first part of my anatomy to arrive. The view would be terrific, however.

Wasn't the prone position used in the movie Flight of the Phoenix??

How would adding surface (lifting) area in the front of the plane move the center of lift (Aerodynamic Center) aft?

 

In fact, adding surface (lifting) area forward moves the aerodynamic center FORWARD, and because it's not a well defined "wing", does so non-linearly - there's more of an effect at high AOA's than at low AOA's (which is a bad thing). This was one of the main reasons that Nat decided to cut the canard shorter to avoid deep stall susceptibility in the wider COZY MKIV - the wider fuselage forward of the A/C was causing the aircraft to be able to reach an AOA at which the main wing could stall.

Now that I have taken my brain Tums and neural Immodium I can more clearly see what I was trying to get at.

Adding surface forward indeed moves the aerodynamic center forward. What I was attempting to convey, before my tongue got in the way of my eyetooth and I couldn't see what I was saying, was that doing that has the same effect on the flying characteristics as would moving the CG rearward on an unmodified plane, necessitating more nose down trim.

I gotta stop writing these things late at night.

Thanks Marc for the correction. The great thing about these fora and lists is that when a mistake is made there are the experts waiting to trounce on the perp--- And rightly so.

How would adding surface (lifting) area in the front of the plane move the center of lift (Aerodynamic Center) aft?

 

In fact, adding surface (lifting) area forward moves the aerodynamic center FORWARD, and because it's not a well defined "wing", does so non-linearly - there's more of an effect at high AOA's than at low AOA's (which is a bad thing). This was one of the main reasons that Nat decided to cut the canard shorter to avoid deep stall susceptibility in the wider COZY MKIV - the wider fuselage forward of the A/C was causing the aircraft to be able to reach an AOA at which the main wing could stall.

Brain indigestion--- sorry.. of course it moves forward.

Argoldman, W&B is of course basic pilot stuff, but I think what we're talking about is beyond that: here the canard moment arm has been increased and the shape of strakes is changed, considering also that the strakes have been changed from a flat surface to a lifting profile(even if the flat surface has a little amount of lift too) this lead to a change that is not just trivial.....

anyway I don't consider yours as an attack to anybody, eventually as a suggest: thank you for you reply!

My original comment was based on the fact that the position of the canard was not changed.

The real question is what effect on changing the C/L the lenghtening of the nose and modification of the strakes has.

Assuming that you don't change the wing/canard distance (which Marc talked about in a prior post), It would seem that the elongation of the nose might push the C/L aft somewhat. Not being an aeronautical engineer (but I play one on the web), I have no idea how much if even appriciable.

Now back to the CG point. Since we have a good idea of where the W&B should be for a stock Cozy, If the nose extension modification is made, even if not, it is important to do the initial test flights with the CG in the middle and test fly from that point expanding the envelope until the CG causes the instability.

I think that this conversation is a great opportunity for all.

Lift is a function of wing area and angle of attack (... and dynamic pressure, etc), so you could just reduce the angle of attack of the canard by pitching the stick / trimming. I wouldn't think changing the structure or the fixed pitch angle of the canard would be necessary.

 

Changes to takeoff trim would have to be determined, but if we're talking a few inches on a 8? foot moment arm, without crunching numbers I don't see it causing a big impact (<-- Well, that's a bad phrase to use).

 

Of course there's the dynamic modes to think about. I'll have to dig out some stability & control books.

Hey, great Idea:mad: :mad:

If you do the trim situation, you may find that you run out of downward trim or downward force on the canard with a rear CG, and possibly duplicate the B-2 accident.

If you reduce the angle of attack of the canard, you will have that effect, however, at a certain point of reduction, and a certain point at the CG, because the canard will be at a lower angle of attack, with respect to the wing, than the original design, the wing may stall before the canard and you will float down to the ground ever so slowly, unable to get out of the deep stall that the scheduling of the stall angle of attack of the canard is supposed to prevent. However if this happens, you really won't probably have to worry about fixing it:sad:

If you decide to change the angle of the canard, do it with plenty of advice from those who know and best from those who have done it and have thoroughly tested their aircraft in more configurations than just straight and level

the CG envelope is there for a very important reason. See my previous post about W&B.

The only purpose that the nasal augmentation serves, other than appearance is to enable you to use less weight to get your CG in the proper place (the arm is longer). You might find that the weight involved in the enhanced proboscis is equal to or greater than the weight that you would need in the standard configuration. But then you would have had the fun of the added construction. This CG change can and should be calculated before you go into surgery.

Just trying to keep you safe.

I would like to know if this affect CG: if you stretch the fuselage and the strakes 12" forward, the fuel tanks also come 12" forward, does not it give a bigger CG difference between full tanks and low level tanks?

this is the reason why I asked about the berkut strakes(stretched or not).

Air,

Any time you make any change it has the ability to affect the CG.

Please don't take the next sentence as a personal attack. It is meant to inform, not only you but others on a subject that may prove less than livable.

If you are not a pilot, you will learn about W&B. If you are, your basic instructor neglected to make you understand what CG and it's calculations actually are.

Please, for your sake, and the sake of your aircraft and the reputation of the E-z types--- Learn all you can about W&B-- perhaps corner an instructor to help you.

With the knowledge of how W&B is calculated, you should be able to tell what will happen when you make various changes.

In certified aircraft, when new radios are put in or even one is changed, the CG is recalculated and recorded.

Anytime you put any kind of weight anywhere other than on the CG itself, it will change the CG (Of course the weight changes too).

If you know the weight added (subtracted) and know the distance from the DATUM, you can calculate your new CG. This calculation will tell you if you have to use some sort of counterweight, if your change will put you within the CG envelope, or if you decide to hang a V-12 Cylinder Mercedes engine on the back, what you have to do to the engine mount and other changes to keep the aircraft within the appropriate CG envelope.

Of course after you finish the plane you will do a weighing CG--- Vital for your airworthiness certificate. It seems that they don't really care if the aircraft falls apart as long as you show them a good CG sheet.

Again don't take this personally. This type of question comes up all to frequently.

Understanding W&B is as important as understanding glassing technique.

Heres a nice little circuit and description:

 

http://www.electronics-lab.com/projects/power/026/

 

Waiter

Wait, Waiter---(couldn't resist)

What are the possibilities of noise coming from this circuit? does the unit have to be shielded (or would that help)?

Along with the carbon spars I need, I am also looking for the tail wheel spring made from fiberglass for the tail wheel version of the Q-200.

Something in my dim memory tells me that some were using reshaped and wrapped fiberglass ax handles for these. But-- don't take my word for it.

Not a dumb question at all.. we've got the glide slope antennae on the floor of the velocity.. one nav antenna in the wing.. the other on the back of the floor of the fuse... all foil.

 

no diplexer needed. no splitting of signal and signal loss.. Just foil.. glass, toroids, coax and tape.

 

And this is on a dual ILS setup (and marker beacon antenna on the keel too, just for grins)

Actually, my post was in the line of a suggestion with canard in cheek. I, indeed have my VOR and GS nested on the bottom of my canard. The only problem that I ran in to was when mounting the BNC connector for one of them (can't remember which one) while measuring where the bulkhead would be, and giving clearance for the thickness of same, the BNC mounting flange interfered with the bulkhead when installing and removing the airfoil,making placement and removal of the canard difficult.

For those of you thinking of putting your antennas on the canard (recommended) be aware that when the canard is removed it must move forward and be rotated upward. Keep the BNC away from that arc.

I have done six of these and found that my laser torpedo level works in lieu of the sight tube. As inexpensive as they are now you can afford two of them. If you understand the geometry and theory on front end alignments, you will be well prepared to take this on. The caster is the angle that your gears legs are in relation to the fuselage. (done right ) The camber will look a little radical to you since the axles WILL NOT be parallel to the floor. Just make sure they are at the same angle while the plane is upside down. When you hang the wings, engine and fill it with fuel, the wheels will be more vertical. The axles will want to slip and slide around when you flox them on. Be creative and build a jig to hold them. If you are not satisfied with one or both of the axles you can break the flox bond, use a hard sand block and tweak the flox pad then epoxy the axle back on. And as the plans say, drill the gear leg after the flox has cured.

What I did was to use a bed of flox and bid for the bed, and orientate the axles approximately correctly. At this stage, it is somewhat like pushing a string. Use packing tape as a separator on the axle and give a little extra thickness on the pad.

When this is hard, using a flat sanding block, reshape the pad so that when the axle is flush to the now modified pad, the caster and camber is correct, and rock is slight. ( I also suggest the use of lasers. Keep in mind that the laser beam has to be parallel to the ground when aiming to the target or all bets are off.)

Now the "flat" pad that you sanded will not be completely flat unless your sanding technique is impeccable. This must be corrected.

Using a new thin bed of thickish flox, Smear some on the hardened, sanded pad and clamp your axle (and laser to the thick new flox with 4 clamps, two on the bottom and 2 on the top. With proper iterations of clamp tightening, you should be able to get your laser directly on the spot.

Of course, you have re taped the axle so you can get it off for future.

Let this harden and you now have maximum contact between the axle flange and pad. Drilling now becomes easy (remove one clamp at a time, drill, bolt then do the next) and your gear will be SPOT (laser) On!

I am about ready to install the axles and I am getting nervous. The plans are not very detailed about this step and I want to make sure I get this right the first time.

 

That primary concern I have is the shape of the main gear strut where the axles attach. It is still somewhat airfoil shaped and I do not feel the 3 plys of bid will not even come close to producing a flat surface for the aluminum plate and axle to mate to.

 

Should I sand the area flat? Should I build with glass layups untill I have more glass to ensure a flat surface? How do I keep the aluminium plate axle and glass from moving during cure (I know that the clamps are there for that, but perhaps there is a more secure method?).

 

One thought I had was to go ahead and pre drill the bolt holes. I have a template that I can use. My thought was that I could layup the glass plys then bolt the who mess together and use the bolts to adjust tow-in. Thoughts?

 

Also the plans method for ensuring proper toe in seem to me to require at least two four armed people.

 

Any hints, tips and advise are greatly appreciated.

 

Here are a couple of photos of my gear with an axle staged. The bottom of the strut is carved out a little differently than plans because I am using Matco brakes....

 

[ATTACH]1718[/ATTACH]

Hold on for a minute!!!

Before you do any drilling, you must arrange the toe in and out as well as the caster/camber/. this can be done with a bed of flox under the axle flange.

Then and only then drill and bolt. If you drill and bolt before this you will have little chance to adjust this-- save some shims, if you are off by just a little. The thickness of the glass on the leg is of little importance save the plans wraps since the axle is compressed to the leg via the bolts through it through the leg through a backplate and then the nuts.

Ain't that the nuts.

Do you have a link to the Midwest engine? I googled for it but didn't find anything.

 

Else, can you tell us more about the Midwest engine please?

 

Thanks

The engine was originally manufactured by Norton for their racing bikes and London police bikes. Midwest took that engine, made a neat PRSU and avaition mount, and got the single rotor variation certified. (They are, I believe, now re marketing this 1 rotor unit under a different name. It probably uses the same parts) They were in the process of getting the twin rotor (the one I have) certified when they closed the company.

It is a dual rotor, EFI and electronic ignition unit of 110HP. It has a dry sump which uses a reservoir of oil which both lubricates the bearings, lubricates the trochoids and cools the rotors. It is a very compact engine, about 10" in diameter and about 2.5' in length. The engine is all aluminum with special coatings for the internals of the trochoids.

If you are interested in more info, contact me with a pm or by e-mail

Single rotor P Port would be lighter

even better would be a Midwest 2 rotor 110 hp 114# dry. I got one.

Hey guys I just picked up my Q-200 kit, they lost the manuals so now I'm focusing on accumulating glass, MGS and all the other associate hardware. I'm even closer to being a builder.

-Guy

Guy, that's terrific. Now all you have to do is cut the canard in half, sweep the wings, put the engine in the back and you will have a side by side veri ez.

Will you be able to get the instruction book?

Dear all, if I would leave of the starter and the magnetos (going for electronic ignition) would I be able to shorten my engine mount by 4-5 inch? If doing so in a Varieze would I be able to use a longer propeller?

 

wolf.

Greetings Wolf,

Your concern is not so much length as it is W&B.

When you shorten the engine mount, you move the CG forward. The important thing is that the CG remain in the confines that are appropriate for the aircraft, which is ultimately determined by the centers of lift of the wing and canard.

The theoretical answer to your length question is yes. How much of a difference will depend on how much you shorten your mount and the relationship between the new and old position of the engine hub with respect to the axles of the main gear.

Keep um rotating

As I've said many times, in theory, theory and reality are the same, but in reality, they're not.

 

But this isn't a question of theory - it's reality :-).

 

Same here.

 

There are two things going on. In the case you postulate, the epoxy starts out at viscosity "X" at time zero. After most of the pot life is gone, the viscosity will increase to "X+17", due to the chemical reaction that begins occurring as soon as you start mixing it. In THIS case, the thickening isn't from heat loss.

 

In many other cases, however, where the epoxy comes out of a pump at 90F and gets spread on something that's at 50-60F within a few minutes, the thickening is (in the short term) due to heat loss.

 

In EITHER case, as long as the chemical reaction isn't TOO far along, heating the epoxy with a hair dryer (or heat tent, or whatever) will lower the viscosity (unless it's so far along that the extra heat merely "kicks" the epoxy into the "B" stage, and it gets rubbery fast).

 

The thickening "starts" immediately upon mixing the two components, but the RATE of thickening is very slow at first, and only near the end of the pot life does it accelerate. At any time prior to that, heating the epoxy will lower the viscosity, but NOT because it's stopping the chemical reaction - just the opposite - it's accelerating it, but the decrease in viscosity due to heat is way more than the increase in viscosity due to increased reaction, until you get near the end of the pot life time (AT THE NEW, HOTTER TEMPERATURE).

 

Make sense?

 

Answerhood, eh? We don't need none of that big-city talk around here, bub.

Ah-- The P(l)ot thickens (as does the epoxy)... Thanks for the explanationhood:cool:

That's incorrect. In the early stages, while still within it's "pot life", the viscosity of the epoxy is highly dependent upon its temperature. As it cools, the viscosity rises substantially. Using the hair dryer lowers the viscosity (and ACCELERATES the cure), but is not changing the "polymerization" from one state to another.

While what you say is most likely correct, Marc, Sometimes clinical experience differs from the basic studies that are done.

I have used various epoxies at both elevated temperatures, from the heater, and also at room temperature.

Using the stuff, at room temperature, as well as at elevated temperatures, I find that after a while that heat "rewets" the material. If the thickening were due only to the loss of heat, where does that heat go. If my hanger is 70 when I start, and the epoxy is 70, and the substrate is also 70 when I start, and the hanger is 70 when I finish presumably the epoxy and the substrate is 70, or perhaps a little warmer due to exotherm, how can the stuff thicken due to heat loss?? At what point does the polymerization and attendant thickening start??? In a pot that answer is easer because of the sometimes rapid exotherm.

Respectfully submitted and awaiting answerhood.

Something else to think about: When I do large or complex layups the epoxy will get kind of thick as it cools off to room temp. Whether I do the layup with plastic over it to squeegee excess epoxy out or stipple, I'll sometimes hit it with the heat gun to get the epoxy flowing again. I've noticed I get a lot more bubbles with it as it also heats the foam and I go back and look for bubbles a few hours later as well. I peel ply EVERYTHING which sometimes complicates the problem. I learned early that peel ply will shrink when heat is applied. You think you have a nice tight layup when it shrinks but it will continue to make problems as it pulls at the layup and causes bubbles. I still use the heat gun when the layup and peel ply is complete so the excess epoxy bleeds through the peel ply. Just not so much heat now.

greetings Never,

It's not that the epoxy gets apapreciably thicker as it cools off (unless you are building at 50 degrees), it is that the material is polymerizing and getting thicker.(going-or getting off) (that's what it's supposed to do) The heat gun does soften the polymerizing material and bring some of it back to it's liquid form.

Peel ply will only shrink if you over heat it too much for the purpose for which you are using it. When you are covering a ragwing, the shrinking is a positive. It will not shrink below a certain temperature and that is the max temp you want to use if you choose to use the heat gun for peel ply application. It is possible that the heat volatilized some of the uncured epoxy and thus the bubbles.

Steve:

 

One of the things you have to remember about canard aircraft is that there is a relationship between the front wing and the back wing. You mess that relationship up and Your canard is no longer a stall proof nose bobbing sleek eze to land plane. It could easily turn it into a large lawn dart. I am not saying it can't be done but at what expense and why is it necessary? These planes if set up right can drop like a rock if you need to loose some altitude fast. I used to do it in my Longeze all the time. I road with Marc Z. at Rough River last year we were a little high on final he cranked it over on its side and started a beautiful slip it dropped like the proverbial rock and we landed right on the numbers. Why do we need speed brakes in the wings? STeve build on.

Additionally you have rudders that can both be deployed outward

Just for grins- do you have a photo similar angle as the naked, cowl off photo- but with the cowl on? Theres a trailing opening in the cowl that is barely shown in the left pic- that I would like to see. I think it is exiting the airflow from the oilcooler on the engine aft boottom? I wonder if he is liking that setup? This lower cowl looks a little bit diff than the one a few posts before. How is his prop taking the exhaust from this vertical stacking? It looks great. Is he liking it?

While at Columbia Fly-in- I was looking at a V8 exhaust that had 4 per side in the trailing edge. I wondered how the owner liked that choice. They were all welded together within a few inches of the openings. I wondered about cracking. Looked very aero- sitting in the trailing edge. I liked that.

If they are welded together, there will probably be cracking. Each stack is a different length and each will expand and contract (lengthwise) in an amount proportional to its individual length.

If allowances are not made for the stacks to exercise this right of expansion, it's cracksville:sad:

So, I'll tell the story as I understand it from Jannie Versfeld and Curt A Smith (ex USA) in ZU-DAR.

 

They were flying from FAMG (near the SA coast) to FALA. On flight plan (IIRC)

 

Jannie had the 3 into 1 pipes, these came out the single opening at the rear of the cowling.

 

The pipe broke at the last join - the tail piece vibrated somewhat & found its way out the cowling, taking a chunk out the prop as it left the plane.

 

The shorter exhaust did heat the cowling some, but I can't comment.

 

The chunk out the prop reduced the max RPM to about 1200 (IIRC) which allowed them to make their way from the Donnybrooke area (REAL hostile terrain) to FAPM, where they managed to organise the world from there ...

I think you gotta put slip joints (and maintain the movement (mouse milk) between areas so that the normal movement can take place without stressing the welds or they will crack and possibly leave the aircraft:mad: .

Chrissi, Randi and Kitty--

Just received my refurbished Gerdes Nose wheel.

WOW:)

What a gorgeous thing. It's a shame that I have to tuck it into the bird when I fly.

Talk about making a silk purse out of a sows ear

Thanks again

As far as I know he is no longer at Bowling Green, MO?

...Chrissi

I know that he had sold/closed the airport/ operation and was planning to move.

Is he still producing/selling parts/kits?????

Anyone contact him by e-mail?

Where can we get prefab strake skins? I know they were available from Aerocad at one time anybody know a source now?

I believe that Al at Aerocad still provides these (Bowling green MO.)