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-   -   C/G testing (https://vansairforce.net/community/showthread.php?t=67570)

Mike S 01-22-2011 10:46 AM

C/G testing
 
I am at the point of my phase 1 flying where I am ready to start moving the C/G around.

This is in an RV 10.

I would like to see how others have done this------What did you use for weight, and how was it secured in place???

I am leaning toward using 25# weights from a barbell set, and rigging up a rope loop through the weight so I can use a seat belt to go through the rope loop, and keep the weight somewhat in place.

Problem is this still allows a fairly large amount of movement of the weight, should I hit bad turbulence, or have a sharp break when I do my aft C/G stalls.:eek:

Sand bags seem to be an even worse idea, as they cant be strapped down very effectively far as I can tell.

So, how do I go forward with this.

Seats in, or out for this??? I am thinking a hundred plus pounds of iron weights on the seat may not be too good for the cushion.

Thanks in advance,:)

noelf 01-22-2011 12:34 PM

I had a similar task with my -6A...
 
...and fabricated a wooden box that exactly fit the contours of the passenger seat position. The internal blocking was designed to accommodate lead dive weights. The weights are easily available in 5 and 10 lb sizes.

I also looked at bar bell weights, but the dive weights were easier for me to fine tune loading configurations.

Van published my writeup in a recent issue of the RVator, sorry, I don't remember which one.

edit...article and pictures published in the 3rd issue, 2010.

N941WR 01-22-2011 01:41 PM

Our EAA chapter has a pile of 00 buckshot bags for CG testing. They work good and can be secure in a duffel bag.

Mike S 01-22-2011 08:50 PM

Quote:

Originally Posted by noelf (Post 506352)
...and fabricated a wooden box that exactly fit the contours of the passenger seat position.

That is one of the ideas that has been floating around in my poor overworked brain. Glad to hear it worked for you.

Thanks for the input.

Mike S 01-22-2011 08:52 PM

Quote:

Originally Posted by N941WR (Post 506358)
Our EAA chapter has a pile of 00 buckshot bags for CG testing. They work good and can be secure in a duffel bag.

Duffel bag-----------great idea, hadn't thought of it.

I will have to see if it will work with my weights, as I dont have that much lead shot.

Thanks,

Kyle Boatright 01-23-2011 07:13 AM

Quote:

Originally Posted by Mike S (Post 506500)
Duffel bag-----------great idea, hadn't thought of it.

I will have to see if it will work with my weights, as I dont have that much lead shot.

Thanks,

That's exactly what I did - duffel bags and excercise weights. I've got plenty of each.

jjconstant 01-23-2011 03:57 PM

+1 for duffel bags...
 
...on a leash. I used rope through the handles and then through my baggage tie-downs to secure them where I wanted them.

Jeremy


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