dcronkhite
 

Hi,
Was just wondering if you talk to Mike a lot? I am very interested in his answers to my questions on all of the H9 1/3 planes.

dcronkhite
 

I do actually.. I'll see him in a couple days when I head up to Las Vegas for the TOC. If you send me the questions.. I'll get him to answer them when I'm there.

-Doug

Mike McConville
 

Here's the questions from 2 previous posts of mine.


Just a few questions Mike, where does all your hanagr 9 planes balance at? With the GT-80 installed, Where does the CAP 232, Extra 330L and Sukhoi Su-31 balance at? Did you add weight to get them to balance? Enquiring minds want to know!!!! I have all 3 and none of them balanced like stated in the ads or instructions, all needed some weight. All of them have the recommended engine Zenoah GT-80, all built according to the instructions. Come on Mike, where did yours balance without no weight? Did you add weight to balance them?

From a previous post:

Received today from Mike McConville

------------------------------
I'm hopeful that almost everyone that is an Aerobatic fan is a Sukhoi fan,
just waiting for a truly refined model to become available. This ARF model
is approx 1/3 scale, 97" span, 1810 square inches. 80cc engine. It comes our
a little lighter than our H9 33% Cap. Approx 24.8 lbs w/ a GT-80 and 23.5 w/
a ZDZ 80 (Single). It took about a pound of lead in the nose when I put in
the ZDZ. Takes no ballast w/ the Zenoah 80. Quality is excellent, and is on
par with, and maybe a little better than the Cap.

Also from a previous post:

with the GT-80, why did it need so much lead in the nose? I thought this plane was supposed to balance OK using the GT-80, supposedly Mike McConville's did with the batteries behind the wing tube.

YO Douggie
 

Hi Doug :D

BV

dcronkhite
 

I think the real answer is simply variation in materials from kit to kit. I have seen a couple of the Caps that balanced without any weight at all, and some that have taken quite a bit.

My Sukhoi is going to balance without adding any weight with a DA-100 up front.

-Doug

oh.. and Hi Bill :-)

BUT 18 OZ.
 

Is there that much variation that some people have to put 18-20 oz of lead on the firewall?

Richard

dcronkhite
 

I'd say it's very possible. Look at the moment arm.. Just a few ounces difference in the tail area can mean anywhere from 3 to 4 times that much on the nose to balance.

With the Sukhoi.. there is another thing too.. that being the length of the standoffs required to mount the engine. A friend of mine had to add almost 24 ounces to the nose of his Sukhoi to get it to balance.. When I looked at his installation.. I noticed he'd mounted his DA-100 directly to the firewall.. roughly 3/4" back from where it should be. 3/4" is a big difference when you're hanging a 7 pound engine/prop/spinner on the front of an airplane.

This isn't an issue with the GT-80 since it's designed to mount up to the firewall.. but the other issue is still very possible. For every ounce difference in the tail, you'll have to add 4 ounces to balance on the nose generally. It's pretty easy to add weight back there too..

-Doug

OK
 

But still would like to know if Mike added any lead, and if so, how much?

My Sukhoi with the GT80 installed balances at 1.5" behind the tube. A lot of posts note that this is a good CG. Is the CG in the manual a little conservative. I haven't flown the Sukhoi yet hopefully this weekend.

Richard

dcronkhite
 

The CG in the manual is very conservative honestly. I've read the same thing you have.. that 1.5" back is a good place too. I'll ask Mike when I see him on Friday but I won't be posting anything until I get home on the 14th.

-Doug