Forward CG 6A

Cadstat · #1 07-03-2011, 08:41 AM

I posted some time ago about my inability to hold the nose off while landing the -6A. I made a spread sheet with formulas so I could quickly find possible loading and resultant shifting CG. I found out I operated at the forward end of the CG on most of my trips around the patch. I added ballast (in the form of a case of pint bottles of water for variable testing) in the baggage as some had suggested in the forum. The spread sheet numbers didn't reflect how great a difference 24 pounds would make but it really made for a much better landing. I was able to hold nose off after the mains touched, something that I couldn't do before. I also learned how amazingly well the 6A can take on all the possible loadings and still be within CG range at gross.

jjconstant · #2 07-03-2011, 10:34 AM

Thanks for the update and letting us know the result of your experimentation. Lots of times folks ask questions, get suggestions and then we're all left wondering if it was pursued any further, and if so, how it all turned out!

I love learning more about these machines and their personalities, both their consistencies from plane to plane and their differences.

Jeremy Constant
RV7A 120hrs.

pierre smith · #3 07-03-2011, 05:19 PM

You haven't told us whether you have a CS prop, a wood prop. or a Catto composite prop...all of which make a big difference.

We also don't know if your battery is in the fuselage, behind the firewall or on the firewall, or whether it's a lightweight PC-680.

Do you have a Landoll crank balancer and so on.....not enough details to offer any opinion.

Best,

jjconstant · #4 07-03-2011, 05:34 PM

Hi Pierre

I believe it's all in reference to this thread:

http://www.vansairforce.com/communit...ad.php?t=73435

I'm guessing they should be merged...

All Best

Jeremy

Cadstat · #5 07-05-2011, 11:57 AM

Jeremy thanks for the link. Pierre you already offered the opinion I needed.

BUT IO-320 engine from a Turbo'd Twin Commanche so heavy heads, long plugs. C/S Hartzel, Battery between petals. Started by B&G. Don't know the weight.
Slider canopy. I'm 185.
Now for the next issue.

If I'm always nose heavy how much is this hurting the top end?
I can only get 170-172mph at 8K. I know I'm giving up 7-9 with the 'A' but I was hoping for 180. I guess the next step is the looking at the prop airfoil. The last owner said I might want to turn up the govenor. I can only get 2600 RPMs in lower FL's which is about what I see on take off at 4680msl. I don't see much MPH difference at all between 2200 and 2400 rpms. Mabye 1-2 mph. Any thoughts?