FlyerInOKC

My Feedback: (6)

I hope the engine didn't ingest any of that dust Big T!

spaceworm

Yeah, we know about dust, don't we?

I grew up in Kansas in the 40's/50's, Duke Foxs' Lustrox had nothing on our home remedy for running in/wearing out engines.

Sincerely, Richard
Cub Brotherhood #187; Sig 1/4, H9 100 inch (Gen 1), GB Anniv Cub
Club Saito #635; Saito 56, 100, 120abc, 130T, 180
Kadet Brotherhood #96; Mk 1 Kadet, Kadet Junior,
Sig Kougar, Sig 1/4 Cub, Sig 1/4 Spacewalker II

BigTeeEldorado

Ya, I'm glad no one could see me cause I know it had to of been hysterical to see me being out maneuvered by an inanimate object. I wasn't sure I was going to be able to find my car after I caught the plane and turned around, it was a total brown-out if you will. All things considered I would rather get my exercise this way than shoveling snow though. I say that with all respect for northern Brothers cause I grew up in Minnesota and had an outdoor type job. Tenacity and a closet full of clothing designed to be worn over other clothing are standard equipment. Along with McGuillicuddy. Flying was always "as can", but didn't ever require a dust mask that I can remember !

BigTeeEldorado

I was enjoying flying in the wind as I have many times before and could see the dust out of the corner of my eye but thought "it won't be that bad, I'll just fly through it". Just in case I had the plane hovering into the wind about 50 feet right in front of me and very shortly realized I was going to loose sight of it. Landing in a stiff wind is always tricky but try it some time with your eyes closed. I lost sight of it about 3 feet off the ground and all I could do was kill the engine and pray. The next glimpse saw it on the wheels so I instinctively held down elevator and ran out to grab it. The little bugger had its tail up, weather vanning and was rolling backwards. Each time I would stop to grab the front, it rolled out of my reach. I finally figured out I had to outrun it and let it roll into me. By that time I was so far away from the group I couldn't see them anymore.

To answer your question....I ingested more dust than the motor !!!

FlyerInOKC

My Feedback: (6)

I have done the same kind of comedy act myself, then again my kids always laugh and point when I run. I tried to avoid flying on those days when their is more dirt in the air than underfoot but sometimes those sand/dirt storms sneak up on you!

Zor

Hello All,

I was observing this morning the pictures of a wing structure.
The accompanying text reminded builders about the proper fit of the web pieces.

It brought to my mind the idea of not using the web pieces and instead have a full span piece in between the longerons of the drawing or the face(s) of the spars.

In other words, instead of having the ribs in one piece and individual webs between the ribs, the ribs would be in three pieces. One from the leading edge to the main spar, a second piece betwen the spars and a third piece fom the rear spar to the trailing edge that would be part of the flaps and aileons.

The one piece web material could be hard balsa or either 1/16" o 3/32" thick birch plywood with the outer layers going spanwise.

Any experience from builders would be appreciated.

Thanks from Zor

acdii

I think splitting the ribs up will harm the structural integrity. You dont want your spars too stiff, need to have a little flex in them or they will eventually crack. Don't overengineer something that has been around for decades without a problem. When properly built, and glued, these wings are very strong, I keep getting ribbed by my fellow flyers that my wing will come off my LT-40, but I built that wing tight and strong, with no mods, and after several hundred flights, doing things an LT-40 should not do, it is still strong. Unless you plan to dirt slam it a lot, or carry weight under the wings, just building from the kit will be good.

spaceworm

You could just build a "Jedelsky" (Jedelesky) structured wing out of 5 ply birch. :-)

Sincerely, Richard

Zor

acdii,

Your experience is much appreciated.

Comments _ _ _

I have been considering that there would be no appreciable difference in weight.
I forgot to mention that the one piece webs would extend away from the fuselage the same as the individual webs of the drawings.

The strength of the wings lift-wise is carried entirely by the spars.
The ribs are exerting any aerodynamic forces to the spars and the airfoil would not be changed.

I have no doubt about the integrity of the present design. It seems to me however that the spars would have more strength and a negligeable added weight.

I have read, a long time ago, that the individual webs should not have their grain vertical ( as is recommended in this design ) but at a 45 degrees angle and the grain on an opposite side at 90 degrees from each other. I forget the name of this fellow from MIT ( Massachusetts Institute of Technology ).

At this stage it is just some thinking and given some consideration. If I decide to go this way the one piece web would be glued to the faces and not in between. The web would be the full thickness of the wings

The final decision can be taken when I am ready to start building the wings. Meanwhile I hope to read more from other experienced builders.

Thanks again,

Zor

FlyerInOKC

My Feedback: (6)

You could go with what my Ryan SC design has, a 1/2" main spar made up of a 1/4" thick plywood and two 1/8" liteply doublers and a rear spar 3/8" thick made up of 1/8" lite ply main rear spar and two 1/8" liteply doublers. The original design I based it on called for all plywood on the main spar and doublers and the main rear spar, I chose to lighten up an over engineered design.

acdii

Well if you model the main spar to a real one, then you would put lightening holes between the ribs, and use mechanical fasteners to attach the ribs to the spars. The real tie in though is that the skin bonds everything into one tight component. If you plan to skin the wing, then using 3 piece ribs would be fine, but if you are just covering the wings with fabric or iron on you lose some of that structural integrity. Also putting webbing at a 45* grain is an ideal thing as it distributes the forces better. Vertical grain is fine if you are applying a load to it like a floor joist, but in a spar setup, having the grain at an angle allows for flexing and twisting forces without cracking. As a wing flexes the top and bottom spars move at different rates, and the angle of the grain pushes against that movement making it stronger and stiffer. Having one piece ribs on the outer panels stiffens the wing against twisting as the grain is front to back.

If I were to do a one piece spar webbing, I would notch it, and join the ribs to the webs and the spars. That way you have the strength of the one piece web and one piece rib, as well as mechanically fastening the parts together into one piece. For even more strength while saving weight, I would laminate the web from balsa, with the grains at 45* from each other, this way you can make it any length you want and be nice and strong, and be able to add lightening holes without compromising anything. It can be inside the spars, like an I-beam, or it could go on the face of the spars top to bottom. Either way it would make for a really strong, yet light wing, and can be covered with cloth or iron-on as sheeting wont be needed to tie it together.

skylark-flier

OK, just to make sure I've got this right - spar on top and bottom, webbing inside or against surface but 2 laminations, one with grain northwest-southeast the other northeast-southwest - and I can put lightening holes through the center of the webbing. How big could the hole be and still have strength?

I'm really liking this idea, looking at incorporating it into a rather flexible (?weak?) wing I'm about to start repairs on for another guy. (older Telemaster)

acdii

Depends on the distance between spars. You dont want a large hole that is between spar to spar, you want some meat between the spar and hole. The strongest would be against the face top to bottom. I would say the hole diameter should be about half the distance between spars, so if its a 1/2" gap, then 1/4" holes. I used to build houses, you should see some of the things that go into making a house today, where the spans are long with no supports. I incorporate some of what I learned into my building when I find a weakness. The laminations are a good example. A 1/8" lamination of two 1/16" balsa, is as strong as 1/8" ply, but half the weight. Crossing the grains doubles its strength. For really strong laminations, balsa, ply and balsa make really good parts.

I worked with my Daughter on Sunday to get her started on her Kadet LT-25. SIG did a nice job with that kit, the spar webbing is notched front and rear and the ribs lock in place. When glued up properly, it is a really strong wing. It also uses diagonal bracing between the bays to keep twist to a minimum.

I also found out, that she was never taught how to use a ruler in school. 4th grade and never taught the basics of a ruler. She learned on Sunday. Her 3rd grade teacher had the gall to tel us not to teach her our method for math due to common core. I did it anyway. Her 4th grade teacher said PLEASE DO! By the time she is in 6th grade she will know how to convert fraction to decimal and back again in her head like I do when building. I found that to be the easiest way to add dimensions and get a true measurement. This will be more than a hobby for her, it will be a way for her to learn skills and math too. She's a smart kid, and I don't want to see her lose interest in what she has. She is learning how to read the plans, and understand dimensions too.

N1EDM

My Feedback: (2)

What a great chance to work with your daughter... My son was like that way back when.... He once found my old slide rule and taught himself how to use it (the instructions were still in it). He wasn't allowed to use a calculator except to check his answers after he'd done the work in his head.

Kudo's to you and your daughter adcii

Now, back to the thread... I don't want to hijack it...

Bob

soarrich

My Feedback: (98)

How can you hijack a thread that is anything about Kadets or how they touched your life?

N1EDM

My Feedback: (2)

I think that the LT-40 is one of the most bash-able planes out there, but it seems like I touched someone's nerve a while back when we got off on a tangent about winglets. Oh well.... I've had 6 - 7 of them. I learned a lot of things on it right now. I'd say that my current version is one of the best ones I've ever flown. I have a buddy who can't wait for our Club's next Open House so that he can fly it as an instructor, giving lessons to visitors.

Thanks, Rich.

Bob

flyingagin

Didn't bother me none

Ken

skylark-flier

+1

FlyerInOKC

My Feedback: (6)

I agree with Ken, I like reading that kind of stuff it gets me thinking outside the box.

Zor

Greetings,

This thread is becoming most interesting as I read the postings and learn new words for me.

I have been familiar with single layer wings given an upper airfoil shape by undersurface ribs.
I now learned that they are referred to as 'Jedelsky' structures. A new word I never read before.

In my search for that meaning I also found half a dozen words to refer to what is most of the time referred to as 'profile fuselage' or 'profile models'; single layer fuselages.

A Jedelsky wing structure would divert too much from the Kadet Senior design ideas ( in my opinion ) and its aerodynamics would be unpredictable ( I believe ). It could be interesting to build separately such a wing without flaps and ailerons, give it about 5 to 7 degrees of dihedral and see how it flies. I think struts would be mandatory for avoiding such a wing to fold off.

My winter house for the three cats that I keep feeding is ready to locate on the rear deck.
They are outdoor cats and wild. I cannot approach them; they run away but they are there every morning and evening for about three months now waiting for the food and fresh water.

That is the project I wanted to finish before the winter weather gets worst.

I might now be able to pursue the preparation work on items for the Kadet Sr.
I am really anxious to proceed with the Kadet. As I said earlier I will not open a build thread; so many build thread all showing similarities. I plan to occasionally show pictures of the progress and particularly pics of the mods from the drawings.

I am not posting pics of some of the preparation items anymore because they are not 'specific' to the original design.

Later . . . Zor

box car

Zor, I am just starting on my senior. I am going to make it into a STOL. I am going to copy what I can off the Zenith STOL CH701. Going to be fun making Junker type flaps and ailerons.

box car

Ch701[attach=config]2052418[/attach]

skylark-flier

Hey, I know the wing but never heard the name before - this is GREAT!! Also, while looking up the name, myself, I found another structure method to wings - kinda like a double Jedelski. Looks to be SUPER light, wonder how strong it might be: It would definitely be an interesting project method to try on a new plane. Anybody else ever built anything like this?

Hey Zor, the great thing about RCU is all the learning - it's almost like going back to school sometimes, but a huge amount more fun. Ye post whatchawant, whenyouwant. It's ALL good.

Zor

We never get bored with watching the birds whether natural or built up by modelers.

Some fellows just like to fly them; thus ARF and RTF.
Other fellows enjoy mainly building them and imagine all kinds of modifications.
A few fellows are more interested in experimentations.

All are hobbyists in their own way and have their own outlook.

Just last evening I spent a couple of hours ( coincidence ) watching the Ju airline flying their Junkers 82 in many world areas including Hoshcosh. Many take offs and landings views from outside and from the cockpit; views of the passengers on board in the cabin; absolutely fascinating.

Now I am given the idea of making a third wing and in time that may actually happen; a wing ( wings ) with the type or roll control on the full length of the wingspan as used on the Junker. That can be done usng the existing wing design and just add extra flaperons ( ? ? ? ) to the existing trailing edge ' a la " Junker's style.
Today installing the cat's winter house on the rear deck. Hopefully next week continuing the preparation work to build the Kadet wings.

When am I to do my Xmas shopping ? Budget limit is $300.00 .

Never a dull moment _ _ _ C U soon.

Zor

soarrich

My Feedback: (98)

Lots of planes have used this type of construction, most famous, in RC away, are the Honker, Honker Bipe, and Top Cat. I've built the Honker and the Top Cat, they both actually use the same wing, the Top Cat's wing is just two Honker wings end to end. The Honker's wing is 36", the Top Cat's 72", The front 1/3 of the wing is hard 1/4" balsa, the rest is maybe 3/16" hard balsa. My Top Cat was doped, I don't remember how I finished the Honker other than I used Walnut stain on it.