Hello everybody!



I just (well 4 hour ago) bought an 53" Ultimate biplane and a NIB Enya
120-4C engine.

The question is: will she fly, or how will she fly? I know it is the matter
of airplane's weight.

My last airplane was an aerobatic lowwing plane of my own design. She was
60" span and was powered with ST61G with tuned pipe.

You could say she was invulnerable with weight over 4kg (9lb). Although she
was "little" too heavy she was quite fast with this engine. Now I have
doubts with my new combination. How heavy may the plane be to get good
aerobatic capabilities? This is question for the biplane experts but all
opinions are welcome.



Best regards

Przemek

Hi,

What is the weight of the aircraft with the engine? Do you happen to know
which company manufactured the aircraft?

You indicated that the wing span is 53". This may be the Goldburg Ultimate
"60" size.

The Enya is not a major power house for the 1.20 size range, but if the
model is in the 8.0 to 8.5 lb range, the engine should haul it around the
sky with authority.

Check the wing attachments, the struts, and linkages between the ailerons.
Make sure everything is solid and that the aileron throw is symetrical to
each other and on both sides. Check both wings to make sure there is no
"twist". Run through the standard "pattern" trim flight routines and make
the adjustments as indicated by the results.

I have owned three different "Ultimate-300"s and the Goldburg version (kit -
not ARF) flew reasonably well with an OS 1.20 once I got her rigged and
trimmed correctly. With a little extra entry speed and the rudder set for
maximum throw, she would do a respectable knife-edge loop. One of the nice
things about the design is that the airfoils, fuselage, and struts appear to
generate a little less drag than many bipes. And yet, it still slows quickly
enough to provide a nice entry into a clean snap roll.

You should have fun with it.

J




"Przemek 'Japim' Jakubczak" <pjak2000@o2.pl> wrote in message
news:b9rcvb$22pp$1@foka.acn.pl...
> Hello everybody!
>
>
>
> I just (well 4 hour ago) bought an 53" Ultimate biplane and a NIB Enya
> 120-4C engine.
>
> The question is: will she fly, or how will she fly? I know it is the
matter
> of airplane's weight.
>
> My last airplane was an aerobatic lowwing plane of my own design. She was
> 60" span and was powered with ST61G with tuned pipe.
>
> You could say she was invulnerable with weight over 4kg (9lb). Although
she
> was "little" too heavy she was quite fast with this engine. Now I have
> doubts with my new combination. How heavy may the plane be to get good
> aerobatic capabilities? This is question for the biplane experts but all
> opinions are welcome.
>
>
>
> Best regards
>
> Przemek
>
>
>
>

> What is the weight of the aircraft with the engine? Do you happen to know
> which company manufactured the aircraft?

Unfortunately I don't know it yet. The model I bought is an unfinished kit
with
fiberglass fuselage and styro-abachi wings. I could even say it is an ARC
version :-)
One thing left to do is painting.

> You indicated that the wing span is 53". This may be the Goldburg Ultimate
> "60" size.

Yes it is exactly 53.14" span. I don't think it is CG Ultimate as the kit
consists of fiberglass fuselage.

> The Enya is not a major power house for the 1.20 size range, but if the
> model is in the 8.0 to 8.5 lb range, the engine should haul it around the
> sky with authority.

I think I should manage to keep it that way.

[cut]

Thanks for advises.

> You should have fun with it.

When I finish her and get ready for the first flight I will let you know
(even show photos).

I have also another question. Where should the CG be?
As I get the second hand plane there were no plans with it.
If you give me the relative dimension in % of profile lenght I will find it
on my plane.
And the last question but not least. What servos should be used to operate
the double ailerons (top and bottom)??
I mean how strong should be these servos?

Best regards
Przemek Jakubczak