Weight and Balance

[Mark33]

Hi everyone! I'm building an RV-7 (tail dragger) and have a question about weight and balance. Does a 7 tend to be nose or tail heavy? I'm building mine with a parallel valve IO 360 and a Whirl Wind RV 200 constant speed prop. I have two Odyssey 680 batteries on the firewall but I'm concerned about weight and balance. I'm also using the "oil-o-matic" pre oiler which is also mounted on the firewall along with the oil cooler itself. I've heard that the 7's tend to be tail heavy so I'm hopping that the extra wight of the items mentioned above will help balance things out a little.....but not to much! With my current setup, the only thing that I may be able to change is the location of the battery (s) in the event it turns out to be nose heavy. Any expert advice?

 

[sirlegin]

You will not know until you weigh the plane.
All RV's are different depending on the build. Look at the prior weight of RV9A's thread for some enlightening information. No pun intended.

 

[David Paule]

Oilamatic Weight

The Oilamatic preoiler on my Cessna 180 weighs 7.0 pounds and its arm is 2.0" forward of the firewall. I just checked my records on that one.

Dave

 

[B Cunningham]

You'll be just fine. Forget about it. My set up is very close to yours.

 

[Mark33]

Thanks guys for the information. So in general, does the 7 tend to be nose or tail heavy?

 

[B Cunningham]

With a heavy pilot, heavy passenger, and low fuel you will approach the aft limit cg. Baggage will exacerbate this. Normally you will fall in the middle. Fwd cg is never a concern. So, in general, aft cg is the limit that you will be concerned with...

 

[Mark33]

With a heavy pilot, heavy passenger, and low fuel you will approach the aft limit cg. Baggage will exacerbate this. Normally you will fall in the middle. Fwd cg is never a concern. So, in general, aft cg is the limit that you will be concerned with...

Thanks Ben! I was just concerned that all of the stuff that I have on the firewall would make me a little nose heavy and that I may need to move my batteries to the back....but it sounds like everything is going to be OK.