We’re finalizing out latest updates (the new Vertical Power electrical system and interior) and condition inspection, so it’s time for a new Weight and Balance. Awhile back I mentioned that we bought some performance scales from Intercomp racing. The process is pretty simple with these, as the load cells can take 1,500 pounds apiece, we just roll up on them, check level side to side, get the nose when on a scale a zero incidence, and take the measurements. Of course, all of the usable fuel needs to be taken off, but that’s usually a minor point. Here you can see our set. I put my name and number on everything because the scales were a bit pricey, and my EAA chapter members like to borrow them (and I want to make sure they come home!).

She came out about 100 pounds heavier this weigh-in. I figure I put at least 20 pounds of electronics in her, between the new avionics shelf and Vertical Power, the new third screen for the GRT, the 2 1/4″ airspeed, alitimeter, and TruTrak ADI, and the CO guardian, so the interior must weigh a bit better than 70. That’s more than I would’ve figured, but the scales don’t lie. We added about 20 pounds on the nose, putting us back at about 125 pounds empty nose weight, right where she did her first flight. We’ll probably ballast her a bit with a salt bag or two on the luggage shelf until we get the constant-speed prop on her. We did also add 60-70 pounds (the new prop and governor weight) to see what it would do, and this drops the nose weight down to a nice 85 pounds.

Also note that we have a couple of Weight and Balance spreadsheets in the Downloads section of the website (click Downloads at the top of the page and select Owners Documents).

Intercomp Scales, they do total weight, per wheel, and fore/aft split	Computer
A set of heavy-duty ramps are handy, I use my winch to pull the plane onto the scales (the winch is a 1,000 AC unit so Beth can attach to the tow bar and put the plane away by herself)	Put chocks on scales to zero them out
Get the plane on and chock it, make sure it’s not resting on the ramp at all	Check Level
Check pitch (checking incidence)

Posted By: Brett Ferrell
Sunday August 7th, 2011 at 9:23 PM

Categories: Final Assembly
Tags: Building Final Assembly Intercomp Scale W&B Weight and Balance