SZD-10 Czapla, scale 1:5

[patte de loup]

beautiful job,
But just one remark ,if I can , I think you use plastic film for covering. It is a shame face to this pretty plane. In addition with "solartex " or something like that , you avoid bubbles. Ok it is longer , but more realistic . for a vintage glider.
BTW your plane is beautifu l Now we are waiting the maidden flight
Pat'

[ultralajt]

PhotoStory:

http://www.youtube.com/watch?v=2u0Ghykj2J8

[loopingfred]

Now that's nice !
Congratulations on a really beautifull job, on a really nice glider

I have the very detailled factory plans for this machine... And I think detailled photos of the full size one, I think from you
You relaunch my interrest for this machine big time !

[ultralajt]

Hi!

I armed myself to the teeth with all Czapla photos that can be found on the Internet, and fellow from Poland send me drawings that I was able to use for making all necessarry drawings and plans.

Off course if someone want to build this glider and make scale cockpit interior, some aditional info (photos&drawings) would be nice.
I didnt bother with cockpit interior for now. I just put two pilots inside (shoulders up only).

I am very anxious about the first flight.

I plan to do it such way:

First "flight" or "jump" will be done in a plain level meadow, (very large without obstacles).
I will use bungee asisted launch. It is a short bungee that can pull 4 kilograms with average speed exceeding 30 km/h. (I test bungee "Mythbuster`s style"...test with 4 kg weight and recording with a camera to measure travel of each frame on the video..finding out a velocity)
At model side of bungee I will use about 50m of line, so if somehow line stay attached to the tow hook, model will be free to fly for about 100m in length. Just a safety percaution, and a way to avoid model to land just to the spike where a bungee is anchored to the ground.

A friend of mine, will hold a glider level and tension the bungee chord . Then he will make copule steps (about 10 steps rearward), holding model level make some fast steps forward and release it from hands. The bungee will accelerate model some 10 feets and model will be in the air. From those 2 meters of height it will glide until land.
I will probably make safe landing and then do all necessary corrections on the trim and controll throws.

Then will do some more short flights.

If everything went well, we will try start model from a little slope above this field (~5m high) and probably will be able do do some S or U flights until land.

And then.... the real slope or aerotowing on the nearest model airfield.

What do you think about the described approach?
Any suggestions? Warnings? Hints and tips?
What C.G: location is better for first start? Forward, middle or rearward (regarding calculated C.G.)...

Mitja

[loopingfred]

Hi Mitja,

When I first test the models, I put the CG to the middle calculated range (never too much forward, well, I try as you will basically fly a truck...).
Then, I do a launch on flat if the model is not too big to be hand launched safely, and then, straight to the slope !
Bungee testing can be a bit tricky IMO as it's never too good for the model safety to have an fast accelerating model, for the fly test, so close to the ground .
On the slope, at least, you have the safety of "altitude" straight from the start, and the possibility to land quickly if something go wrong. (depending of the configuration of the slope of course)
So, for me, test flight, first, a launch on flat to see how the model react, to start to "feel" it.
Then, slope or tow straight away

[ultralajt]

Thanks a lot!

Mitja

[ultralajt]

I am finished with work and now praying for a nice weather tomorrow.




I set controll surfaces deflections:

Rudder: 30° left&right, 30 EXPO
Elevator: +/- 20°, 30 EXPO
Ailerons: down 10°/up 15°, 30 EXPO (frise type ailerons)

What do you think? It is my judgment, but I dont know if model will be lazy or too lively....

Mitja

[ultralajt]

Hi!

Today I made some short flights with a model.
I need to add some nose weight and lower the controll throws, as model was lively and nervous when flying.

But awerall feeling about model is pretty well. I think, it will be a pleasant flyer after CG and deflections will be properly set.

Here are some photos and a short video (click):

Model assembly on the field.














I use 40m of a thin chord and 6 bicycle inner tyres as a bungee chord, joined in length. It was about 20 steps of usable elasticy..just enough for a nice asisted launch of the model.





















Next flights will be much easier now.

Regards!

Mitja

[ultralajt]

And one vintage look short video clip:

http://www.youtube.com/watch?v=2Lj3SJDzVDo


Mitja

[Frédéric]

Hello Mitja !

Splendid glider !


Amicalement
Frédéric

[patte de loup]

hello Mitja,

Congratulations
Seiing your maidden flight, I am sure, you are not so far for taking some big pleasure with your glider
Pat'

[Texier Serge]

Very nice !!



I like a lot your approach of teaching in your Posts, in the presentation of your pictures and your videos.

Good luck for your next flight.

[caralp_laurent]

Hi Mitja,
very nice glider and little bungee flights !
It seems to be light isn't it ?

Congratulations !

Lolométéo

[cw]

Nice job Mitja...

[ultralajt]

Thanks!

Hey, great news!!!

Today I was present on an aerotow meeting. A giant Piper towing plane take my Czapla to the heights!

I was very concerned before the actual towing as it was my first time. But they told me, it was just O.K. for a first timer. I jump a little to much up and down behind a tow plane but we manage to rise to decent altitude.
I trim a little to down and right and then enjoy the graceful slow flight of the sailplane. I think, I even made some turns in a brief thermall, but I was too concern of aquinting myself with model, and more concentrating to pure fligtr rather than centering a thermal. I was a little high at final, but I didn`t want to risk another 360° turn, so I open brakes, make some "S" approach and manage to land on the field.

Now I am more convinced about the plane and my ability to fly it, so next step is to fly on the slope, when apropriate wind will starts to blow.

But of course I will attend next gathering of aerotow enthusiasts in a month or so...

Some photos of today`s meeting:



Assembling the glider.







Group photo.



Parking....



Towplane, semiscale Piper Super Cub







My Czapla was only Vintage.. all others were glass ships...



Some of them really big and elegant....


And a short VIDEO of first aerotowing (click)

Regards!

Mitja

[GuillaumeG]

Congratulations for your first towing and real flight with the Czapla!!

Very nice flight and video. Enjoy the next ones!!

[Stephan]

Mitja
congratulation for this nice glider and its first flight. Only one remarque, the towplane was by far to fast
Cheers
Stephan

[ultralajt]

Thanks!
I will try to enjoy next fligts indeed.
Regarding the speed of aerotowing, maybe those vertical oscillations I made with a glider was partly induced by my unexperience in towing and partly from a fast flight of towplane. More speed equalls more sensitive elevator...

Some pilots said to me after my flight, that I should just to controll the roll axis, and not bother much with pitch as glider will take a proper altitude behind towplane by itself, as his nose is pulled by a towing rope so he cant drift a lot from a towing direction.
Well, next time I will try to pay more attention to that.

Just now I am waiting for a proper weather forecast, to fly on the slope. I would like to fly slope as there you can enjoy glider flying very close and see it clearly. You can fly at eye level, but model is still high over the ground. I would like to make allso some nice flyby photos and video clips.

Yesterday the light was bad and was no good for shooting...

Now this project is moving to its end and about in a month, a SZD-10 Czapla KIT complete should be available for the builders.
Wait for further info here!

Regards!

Mitja

[ultralajt]

Hi!

An unexpected outcome of this project just happens to me!

I did not agree with option that give me "would be" KIT producer, that ask from me designing of this sailplane, so now I am free in search for another KIT producer, that is maybe interested in this sailplane.

If I will not find a producer from Europe or East, I will probably start to sell plans and files on my website.

See here for further information, if you are interested in KIT production and sale:
http://ultralajt.webs.com/szd10czapla.htm

Regards!

Mitja

[ultralajt]

Hi!

Today I made a first flight on the slope with Czapla!

It was even better than I imagine!

I was amazed with agility and soaring capability! Model responds very prompt on the controls, but they should be very harmonized and coordinated. Strong use of rudder is needed when put in or out of a turn, but then Czapla can turn in very small radius (look at the video)

There were a little low wind and on moments it allso dissapear, but luckily some thermalls save me a couple of times. Model soars very nicely.

At some higher speed the voice that model produce sounds very "vintage" and it is awesome to hear it!

Here are some photos, and at the bottom you will find a link to teh short video of that flying.



Assembly of the model on the starting place.



Checking the model and waiting for a headwind.



Starting! What a figure?!





































And a VIDEO (click)


Regards!

Happy Mitja

[czirh]

Nice slope soaring & video..
Congratulation..

[Olivier]

She's a beauty...

Congratulations !

[ultralajt]

Hi!

Long time no see....

Czapla is stil alive. It went under minor maintenance work.

Last week, I replace the clear plastic on the canopy as I want to place mini camera in the cockpit and old canopy was not so clear. There was some "foggy" places on the canopy as result of CA glue fumes.

Another thing was that I noticed in flight tendency of the model to bank left. Model need quite a lot right aileron trim. I find out, that right wing is lighter than left one and that left wing has slightly lower twist as needed to be.

I clamp wing on the bench, twist it and heat it with a hort air gun. Left uder twisting load for couple days and check the new twist. It is not perfect, but close enough. I am still afraid that this is not permanent solution. Hopefully teh balsa skin combined with tension and heat will remain in newer shape.....

I also glue some lead weight into right servo bay (aileron servo) to statically balance the wings. 24g was needed. Hopefully that will do...

On the sunday I will go to local aerotowing meeting, where I will test those modifications. I hope that the weather will be fine.

I am looking forward to take some cockpit video clips!

Mitja

[ultralajt]

Yesterday we have a meet of Scale gliders in Ajdovscina airfield.

I made 3 tows with my Czapla.

here is a video clip of first one!

Enjoy!

Movie (click)



Mitja

[Anonyme]

Very nice video, it would be nicer if the pilot could turn his head on the left and on the right ! Maybe in next vintage scale sailplane model ?

[ultralajt]

[Anonyme]

You can also directly place the camera inside the pilot's head and film through his eyes !

[ultralajt]

[ultralajt]

And another movie with flight No2 and 3.
This time I didnt use music background from Polish author, but instrumental music that I find more apropriate for soaring...

VIDEO2: http://www.youtube.com/watch?v=-nT_khoH5EE


Mitja

[czirh]

Hi Mitja,
beautiful videos, congratulations...!