Yugoslav U-AGD/YU-AGS & "Jet-like Trainer" projects

[hesham]

Hi,

the Yugoslavia designed in 1991 a jet-like twin boom aircraft project,
it was powered by one Turbomeca TP-319 310kW turboprop engine.

http://www.flightglobal.com/PDFArchive/View/1991/1991%20-%201738.html

 

[Tophe]

Interesting. The text does not detail the precise location, I wonder if this airplane (if built) would have turned Serbian or Croatian or else now...

 

[Kdmoo]

I had this in my archives. Not sure what it is?

 

[bigvlada]

Lion's share of the SFRJ aircraft industry was in Serbia because it had several aircraft plants before ww2 and biggest experience (scout planes were used in first Balkan war in 1912 and first plane was built in 1908). Some of the factories were dislocated from Serbia to Bosnia after ww2 because Tito feared the Soviet invasion after the split with the Stalin in 1947. The relations improved after Stalin's death in 1953.

This is a project of Faculty of Mechanical Engineering in Belgrade, which has proposed building two aircraft that would fill all the tasks that agricultural aviation was expected to perform . A smaller plane was supposed to have a pushing propeller mounted behind the fuselage with a turbo-propeller engine, which would be more expensive initially but cheaper in the exploitation of the engine. Due to the construction of the vehicle, they claimed that it would have a helicopter flight safety, and for the safety of pilots, in front of the plane deformation aluminum surface (nose) was set that would protect pilots and plane during the crash.This single engine aircraft was named YU AG S (agricultural, single).
YU AG D (agricultural,double) was twin engine design with propellers mounted on the tips of the wings set in rings in order not to disturb the flow of air and to spray treated surfaces evenly.

my city military forum has the whole document (above picture is just first page) in english
http://www.mycity-military.com/Avijacija-i-PVO/Jugoslovenska-vazduhoplovna-industrija-posle-WWII_2.html#782426

 

[Tophe]

Thanks for this expert analysis and interesting link.
Is Yu-Ag-S the name of the twin-boom version? Yu is for Yugoslav obviously but Ag like Agricultural? S like Single engine?

 

[bigvlada]

Yap, Yu-Yugoslav, Ag-agricultural, S-single. No, twin boom version was named D (double).

The funny thing is, this project could still see completion. A lot of countries need cheap agricultural plane (one of the good things about these two designs is that parts are interchangeable as much as possible (I believe, and this is unverified, that 80% of the parts are identical for both planes)) and I can see these planes fulfilling this role (hell, An-2 is still used in Serbian agricultural aviation).

The other thing is, Utva aircraft plant that was bombed in 1999 is again operational and is currently producing Lasta 95 light trainer aircraft for Serbian and Iraqi airforce. This project is also more than three decades old but produced the bird in the end after all. AG-S and AG-D are on the same technological level with bigger potential market. If the Lasta sales increase, maybe even the modified Super Galeb G4MD jet trainer will see mass production (Did you know that the US Airforce was considering using its previous version as a trainer in the late eighties?).

 

[Tophe]

Do you know if the Stanojevic S prototype has ever been completed? (scheduled in 1991)
Source: Jane's All the World Aircraft 1990-91

 

[Tophe]

This trainer seems related. Completed too?
Source: Air International August 1991

 

[Tophe]

Maybe this is the same subject as this one http://www.secretprojects.co.uk/forum/index.php/topic,3456.0.html sorry (to be merged?)

 

[Antonio]

merged topics

 

[bigvlada]

A few more scans of the YU AG S/D, known also as ppa-1 and ppa-2 (ppa - poljoprivredni avion - agricultural aircraft).
One of the reasons for the victory of this project was it's adaptability. It's jet like trainer version was posted above, and on the last picture a few more versions are presented.

 

[Tophe]

One of the reasons for the victory of this project was it's adaptability.

Victory... do you mean: ordered and built and flown and bought?

 

[bigvlada]

It won the competition, if the country didn't disintegrated as it did, it would have been built. With the revitalization of the Utva aircraft plant (it currently builds Lasta 95 basic trainer) this bird could still fly. We'll see.

 

[Tophe]

After 20 years waiting, either it would need update installing modern engines, or else it could provide a cheap aircraft, cheaper than brand new designs...

 

[bigvlada]

Well, it's agricultural aircraft, not stealth fighter, they age slower The intriguing part is that the authors claim that putting those circle hmm, casings around propellers makes them 30% more efficient on low speeds (less than 250km/h).
It would certainly be improvement, because we still use those 17 different models.

 

[Tophe]

I think you are right for most parts.
Just, don't forget the principle of capitalist-market economy: each manufacturer wants to be alone on the market, saving funds for customers by common stocks of parts, centralised maintenance, decreased advertisement, then - when competitors are dead - it raises the prices to get maximum benefits... and the customers regret the time when there was competition to control prices down for success over concurrence. Only two or three main competitors can raise prices together secretly, just minor competitors would propose cheaper heretic ways. This is not simple (I am not expert at all), but such an aircraft designed in communist surrounding has much to invent to succeed in a capitalist new world. Technical efficiency is not the main key, maybe. Good luck!

 

[bigvlada]

Heh, we were a strange bird although Yugoslavia was a communist country. It was not the part of the Warsaw pact.Yugoslavia chose to form non-aligned movement (check the US and USSR press from 1961 and you'll realize one of the factors that led to the demise of that country) People believed in communism and they had the opportunity to go to the west or east whenever they wanted or liked. Workers self government in state owned factories and visa and master card among average citizens. Foreign goods were scarce and burdened with high import taxes, bureaucracy was horrible. Political plurality was nonexistent although you could buy foreign press freely.
What I wanted to say was that those projects were created using market based economy principle. Light trainer Lasta 95 was the project from the same period (first flight in 1985), and 20 were delivered to Iraq this year, beside the Serbian Air Force. That's why i believe that those agricultural planes have the chance to became reality too.

 

[Tophe]

Interesting background analysis: these facts are not well known in the Western World, where propaganda (against Communist countries) was/is more common than analysis... I hope this will provide this twin-boom agricultural plane with a chance to conquer the skies...

 

[overscan (PaulMM)]

Model pics of YU-AGS/AGD


Source: Aerosvet International Issue 1

 

[overscan (PaulMM)]

http://www.mycity-military.com/Ostalo-3/Jugoslovenska-vazduhoplovna-industrija-posle-WWII_4.html


Posted earlier - has lots of original material so adding to topic with light photo editing.

 

[overscan (PaulMM)]

More...

 

[overscan (PaulMM)]

More:

 

[overscan (PaulMM)]

More:

 

[overscan (PaulMM)]

Last ones.

 

[hesham]

My dear Paul,you made my day,very cool.

 

[hesham]

From Aerosvet 06-07,


here is anther pictures to a model of this aircraft.

 

[hesham]

Also from Aerosvet magazine,


here is some of its variants.

 

[hesham]

As request from Richard N,


here is the next page in two pieces.

 

[hesham]

Also the last part;

 

[hesham]

From JAWA 1991.

 

[majevica]

This trainer seems related. Completed too?
Source: Air International August 1991

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