Hi,

What is the purpose to use retractable landing gear on Orion? Is it not suppose to fly rather slow? And then it does not matter much if the landing gear are down and creating some drag. Sure it will be a cleaner plane with less drag,maybe little better center of gravity when wheels are upand look little cooler with landing gear retracted. I was just curious about Your argument(s) for using retracts on Orion that was not designed to need it.

/Bo

Bo,

I am an instrumentation engineer and I am interested to design and built ANY part of my planes so also retracted gears. In the past I did make retracts already in pattern planes to experience the problems and results see the black and white pictures, Mäxi, with shorter nose and electrical activated retracts.

So in my situation it isn’t the question, why do you make retracts in an Orion, but, why do you use an Orion to invent retracts. This is the answer.

In the past it started as a Taurus, but after conversations, many years ago in a Taurus thread on RCU with Jim Messer, I did change my project to the Orion, two legs.
The fat wing of the Orion (or Taurus) has a lot of space to built in and try out an own designed system and the Orion did make already hundreds of flights until that spar he met and lost a wing.
Now I am finishing the design of the second generation gear set of my Orion.

My goal is design, build and use own designed systems and retracts are a real challenge!! (force distribution, fail safe, weight, complexity, maintenance, used components)
For example, because leakage is often a point of intention I do use only 3 o-rings in the whole system with plenty of spares!!!

So profits are, learning (most important!!) and nice to see (last picture) but not speed or flight characteristics.

Remarkable is, the Orion is/was 10 pounds , 4,5 kg and does fly excellent with a ENYE 60 4 stroke, so reduced drag maybe is a profit. The weight of the plane I always have to keep in mind when flying the plane (climbing!). Now, after finishing the plane next week I hope I did save some weight, but I still do not know how much. The reliability of the system again is most important.

About designing, I am preparing a new post about pneumatic retracts systems: “Wheel collar or constant differential pressure relay?”
So stay tuned about the retracts! Maybe in the future to show the “commercial suggested” method and an industrial solution for my Orion to control the speed of retract.

Cees

Bo,

No prove without showing the move.

http://www.rcuvideos.com/item/HJ1KT02BD9N05GK3/received

I did a cycle test before make the sheeting over the wing.
First movie also to show you how Hanna my quality assurance employee have fully attention for this test.

The cycle test is to count the amount of usable actions, the restrictors are not yet adjusted.
Air tank pressure is 4 bar and the first 5 or 6 cycles are really usable and enough.

More to come

Cees

So, leakage test finished with good result.

After the movie is made I did not change anything on the plane, now, 24 hours later the legs are still ”IN”. So leakage test is also oké

Reliability has a lot to do with complexity and amount of components, that’s the reason I prefer pneumatic above electric retracts. Also fail safe is easy to realize.
For me the retracted position is as important as the "tract", I prefer belly landings outside the field or when there isn't enough length , normally without damage.

In the industrial instrumentation in the past we did use a lot of pneumatic equipment; measuring instruments, analog controllers and valves, calculation systems etc. Some brands: Foxboro, Bristol, Honeywell, Siemens, Moore.
It isn’t strange we also did see pneumatic control systems in our modeling in the past, read about Karlheinz Stegmaier and Omu. Pneumatic equipment was used in 1960 and 1962 during world championships pattern flying. In 1962 there were still 3 pneumatic systems used.

More to come

Cees

Gents,

Some construction pictures of the Orion.

Background: The Orion is designed for belly landings, only when the surface is good enough I use the wheels.

The sheeting of the wing in front of the wheel main legs is 3 mm balsa plywood (1/8 inch) .
The sheeting of front part of the wing centre section is birch plywood 3 mm.
The LE of the wing is also covered with birch plywood, 1mm
The wheel legs and covering will be positioned behind the balsa plywood wing sheeting when retracted. So the balsa plywood will protect the legs for damage during belly landings.

Second picture you see the engine protection, the pine headrest is to protect the engine mounting. There is a gab of about 0,5 mm between the headrest and the valve cover. So the engine only makes contact with the headrest during belly landings.
The high positioned air intakes for the engine cooling is also used for the carburetor combustion air. This high position and over pressure in the plenum chamber will keep out dust and sand from the engine air intake during belly landings (I hope).

So, did we see the Father of the Oldest Taurus on Earth, Orion, with three wheels in 1961, I often use no wheels !!
It is whatever you want to make also your plane a winner.


More to come,
Cees

Gents, one more picture.

Classic pattern flying, to show all was allowed to win.
Most important and best rule ever was, you did have to built your own plane. When you could not fix that in a few months, you already were one of the losers for the next season.

A picture of the inside of the wing, location of the right main leg.

All these pictures are helpful in the future when looking back at the results of the several designs and modifications.
First generation was single pivot (double ball bearing bolted together, 8 mm axle) and very heavy. About 10 modifications after the first flight of the Orion and over several years. The legs were easy to mount with two bolts on a plywood plate on the main spars.

These (second generation) legs both have two pivots, plain bearings (6 mm axle) with distributed mounting points. Light but complicated to align the two pivots, That’s also the reason for the glass reinforced plate to mount the front pivot block on.

The new legs have some very strong positive points, cost prize and weight. Interesting to find out the quality.

Cees

Gents, to make a story complete.

I did make a post about mounting the tank in a Taurus (or plane without a hatch above the tank, see post 678.

http://www.rcuniverse.com/forum/fb.asp?m=9562117

While mounting the tank in the Top Flite Taurus, I discovered the job is more easy, especially wen the lines were already used, after winding some thin tape around the end of the line and steel spoke.
See the picture and the blue arrow.

Cees

Flight report,

Preparing for a demonstration in Umtali, Rhodesia 24 April 1962?
No, in Lienden, Netherlands, 24 April 2010. 48 years later

Pictures of my visit at the vintage meeting in the Netherlands with the two Taurusses from the crate of Africa.

The Top Flite Taurus did make 4 flights after the overhauling and the detailed new paint scheme with original Taurus name.

Cees

Gents, IMPORTANT

The foe of the modeler is the friend of the supplier.
“Fuel and oil on the wrong places”, in the engine bearers and under the covering.

First the bearers,

I do have to ”service” the fuel pressure controller so it was possible to make a picture of my way of mounting the engine on the bearers of my “Top?” Flite Taurus, that was also the reason for this post!.
The bottom of the engine room is closed, no nuts or whatever visible. The bearers and wood in the engine room is covered with two component epoxy.
The bolt heads are soldered on a metal plate, on bottom side of the bearers, and glued, with white glue, in the drilled holes of the bearers. The engine is mounted on two glass reinforced plates that are also glued on the top side of the bearers with epoxy, see post 707.

In case of a broken bolt I can remove them with a solder iron, that’s the reason to use white glue!.

I did remove the thread of the top of the bolts. for easy mounting of the nuts.
Each bolt has a ring-nut-lock ring-nut combination to mount the engine, see the first picture.
With this way of mounting never any engine will leave, unwanted, the room.

I use MVVS 10 CC and OS Max 61 FX, they do have the same positions of mounting holes.
After 6 years and after the overhauling, the engine room is still “as new”.

The tank compartment is painted several times and I drilled a 3 mm, 1/8” drain hole on lowest point to detect any leakage of the tank. See second picture.
(This is not a rearview mirror but the bottom of the tankcompartment!)


And now the covering,

Learn the “classic” story of the “Trojan Horse”.
I predict you, in the future you can buy model airplanes and some of them with kind of supplier friendly heat shrink covering, and these Trojan Horses are not from the Greek in that situation.
So you are warned,

Cees

Gents,

Already did make some calculations of the ratio of distances of the fuselage of the 150 % Oldest Taurus on Earth, Nose – LE wing - TE wing - LE stab - TE stab.
If people are interested in de way “how to”, redesign, let me know and I can give some explanation about the calculation method I use.

More to come?
Yes I will look for some more pictures of the vintage meeting in the Netherlands.
It looks like it will be organized again next year so we have to build new planes to show, all to do with the Oldest Taurus on Earth.
I am not sure what to built first? Les Fruh, Simla, ...........

Cees

Some more pictures of the vintage meeting in the Netherlands,

There were a lot of airplanes, scale, sport, gliders, helicopters.
I only did make a choice of the pictures of pattern planes of the past.
And of course two of the Top Flite Taurus

Cees

Gents, history

Does someone has more information about Curt Dimberg?
Curt did built the (+)100 “ span pattern plane a few years before the Simla is released.
See the picture.
Cees

Gents,

Designing and building.

Imagination, sketches, calculations, drawings, visualization. It is an important step by step process of realization of a new object, mechanism, circuit or plane.
Imagination and sketches sometimes are steps I make in the middle of the night, just as prototyping.
Can it work, how does it looks like, what is a value or dimension, would it be nice?

Example:
Would it be nice to have a Simla on the next vintage meeting in 2011 and how does it looks like.


For the spectators:

Simla, third Taurus and most modern contest Taurus ever, special designed for proportional radio and the pattern program of the period 1965 and later.
All airfoils are fully sheeted and the plane is designed for a side mounted 0.60 cu / 10 cc engine.
On the picture, my copy of the Simla of Ed Kazmirkski, one of the Simla’s of the past and of course also a Detroit winner. This is a “study picture”, so this Simla deliberately does NOT fit in original pictures!! In the future I will prove, it is a whisper of a penny to build the exact copy,
For me it will be again an interesting process of learning and combine all kind of methods to do my hobby, rebuild the original pattern planes.
With “one of the Simla’s of the past”, I ask the special attention for the fact, there were more Simla’s!!

Angles do not play with us, we play with angles.

We do not find a development story of the Simla, but did the plane drop of the air? No again of course not! The design process of the Simla did already start with the realization of the Oldest Taurus on Earth, spring, summer 1961. That’s the reason the crate of Africa is also the cradle of the Simla. What’s my profit? I know any detail of that crate and so also the cradle of the Simla and do not have to guess or make choices as others have to, so angles do not play with us but we play with angles.

Visualization

Visualization, one of the nicest steps in designing. Building the plane already and share it with other modelers, without dust, before the final realization.
Realization? Ed already did show the plane was successful so we, Hanna and I, don’t hurry.

Cees

It's a shame nobody will ever be able to prove exactly what the Simla was in all aspects, but I look forward to seeing the construction reports from the alpha kits now under construction. What will be really cool will be seeing one of them on the parking lot in a recreation of the inspirational photos.

Let's hope nobody knocks a lamp over!

Andy

Andy,
You can write that about any champion plane (bolted). Making a drawing to sell, a kit or a ARF only has commercial backgrounds and for that is not interesting for us. Our goal is to make a copy of the original as good as possible. That is, no limitation in time, effort, methods and costs.

Hanna and Cees.

NOT INTERESTING TO "US"?!?! Surely you only mean you and your cat.

My interest in contributing to it was to have as accurate a model as possible, and to have it commercially available. I think pretty much everybody who contributed shared an interest in seeing accurate kits available.

Andy

Andy,
About Hanna, you are right.
About your contributing I read your goal is a modern Simla. We have other, more original goals.
See the picture, an impression of the vintage meeting in the Netherlands next year. Maybe!

Cees

You must have missed something in the translation to Dutch.

Andy

Andy,

If “modern” is your point!

We prefer original construction methods, even silk an dope, so we keep on to develop our skills as they did in the past. Also we redesign the plane with adjustable wings and one analog aileron servo.
My radio is not a computer radio and about 35 years old, I will use no mixers nor dual rate, so also that will be as original as possible.
I am even thinking of reducing the speed of the servos so they are as fast as the old 2,4 V analog servos. I can select reduced speed (on/off) with my translitter if I want.

When you read this you will understand that nearly any model airplane these days is “modern” in our vision.

Cees

When you decrease your servo speed, be sure to decrease your servo torque too, or you will still be "modern."

And while you're at it, don't use a PPM radio - after all, Kaz didn't.

And be sure you use paper instead of electrons to send your messages. After all, Algore hadn't invented the Internet yet. And no fuel injected automobile to get to the flying field, either!

As you can see, change is not necessarily bad. Construction techniques change as people find better ways to implement them. You can have a computer radio and still have limited performance by leaving it in the default settings. You can decrease servo speed with a computer radio, but you can't reduce torque that way.

"Modern" isn't construction techniques or installed electronics. Modern is aerodynamics and power:weight, handling and performance.

Andy

Andy,

Servo positioning systems are often used in my profession, so let me explain.

As long as the needed torque is less than the max the servo can generate the speed will be (nearly, loop gain!)) the speed of change of the input, so the limited speed of chance of the output of the transmitter channel.
Limiting the speed of the servo will reduce the needed torque of the surfaces so the modern servo will be strong enough.
In the past the problem was the limited generated torque of the servo. I still remember we did use AC127 and AC128 or AC187 and AC188 germanium transistors and 2,4 V to switch the power of the servo motor. It all was a little bit limited!! For that reason it was better to use one servo and I still do.
Pro is, the ailerons always are synchronized!!

My transmitter is FM modulated, not AM but that does not has influences on the flight characteristics just as the other points.

The car: Chevrolet, so “All in style”


Modern see post 1954:
http://www.rcuniverse.com/forum/fb.asp?m=9590120

Cees

Gents, for who is interested,

Some people will remember my drawing of the Perry pump after our research, picture 1 , but what's this? picture 2
More to come.

Cees

Picture 2 of the last post has nothing to do with fuel injection.


Off topic
Hanna was very ill for period so we did use fuel injection. It is going a lot better already.

Cees

Gents,

Process of idea to first prototyping and realization of the useable result is going on, also for the “controller”(picture2) of post 722, a process of years. Normally only the result is interesting for you when you can buy it.

How about this process of the realization of a champion model pattern plane. Thinking about the Simla-Taurus I am also interested in a comparable plane, there is one.

Some keywords:

Designer and builder did look to the real airplanes to have a visualization of his new plane.
Both were Mr. Ka
The development period was a project over several years and prototypes.
The designer and builder never became a world champion with the plane himself.
After the first kitting of the plane after several prototypes it became world famous

What can we learn when we look to the stories of these two airplanes?
There already is done a lot of organized work before the realization of the plan, kit or ARF before you can buy.
Believe me these planes did not drop of the air.

More to come

Cees

"The World According to Cees...?"

Gents,

Why did I start this thread?

I did start this thread to show how I did reconstruct the oldest Taurus on Earth, visible on the crate picture, the high resolution picture I have from the estate of Ed Kazmirski.
It is not believed, read for example this post of Duane Wilson and Evan Pimm,

http://www.rcuniverse.com/forum/fb.asp?m=8793099

or this one:

http://www.rcuniverse.com/forum/fb.asp?m=8853456

or this one:

http://www.rcuniverse.com/forum/fb.asp?m=9602877

To show you an other side of the story, some posts of the members of that same team. How capable are they in recognizing a champion plane, the Dalotel of Hanno Prettner, 10 May 2010.
First post, Ustik thinks the plane did have a blue bottom side, so what do we do? As he did before with Taurus pictures, change the picture by photo shopping!

http://www.rcuniverse.com/forum/fb.asp?m=9723124

“After playing with the white balance I think these findings (especially the blue) are quite reliable.” (Ustik)


After seeing this post of Ustik I was triggered, could not believe the refrigerator pictures are reliable and as I normal do, double check.

http://www.rcuniverse.com/forum/fb.asp?m=9723227

Bottom colors are purple, no doubt!

In post 73 RFJ shows us probably the “example” picture, some other, really blue bottomed duck!
http://www.rcuniverse.com/forum/fb.asp?m=9723453

Story continues on the next page, post 77 indeed a complete different plane they did use as an example!

Crate picture?

Only when you design and built model airplanes yourself for a long time you will recognize the differences immediately.
If you don’t? You have to be the friend of any kit cutter or other supplier.

More to come.

Cees