RV-7 weight numbers
I completed the weight and balance on my RV-7 today with the following configuration and results:
Engine: IO-360M1B with dual PMAGS
Prop:Hartzell 72" Blended Airfoil CS prop
Dual Andair wing root gascolators, Andair fuel pump, Andair fuel valve.
Single G3X Touch IFR panel (GTN 625, G5, heated pitot, autopilot etc...)
Electric pitch and roll trim
Night lighting (flyleds Nav/Strobe and Baja Squadron Pro landing lights)
Tosten military grips
Airframe fully primed internally (Ekopoxy) and fuselage fay sealed.
Canopy Supertracks (best mod on the aircraft)
Sikaflex Canopy and Carbon/Glass skirt
Full carpet (walls self adhesive "fossliner" 340gsm, baggage and seat pan with 490gsm Spectropile and forward floor with Autex Reef 800gsm)
Forward floor 3/4" sound insulation foam.
All Van's seat cushions/spacers installed (canvas covered)
5 point Crow harnesses.
EarthX lithium battery, single alternator
Oversized 380-150x5 tires (second favourite mod)
JD Air Parts Tailwheel assembly and vent/drain fairings.
Ceramic wool/stainless firewall protection
Titanium/ceramic wool belly fire protection
Full external paint and all fairings in place.
Unusable fuel (22lb or 3.68gal total)
Total Empty Weight: 1135lbs
Empty Arm: 79.35"
Tailwheel weight: 62lbs
So it appears I built a bit of a pudgy sucker. I focused hard on keeping the CG forward during the build, which I achieved, however I blew my target weight by 27lbs. It's amazing how all of these little mods add up, even after the lithium battery weight saving. With two 170lb people on board and full fuel I'm limited to a baggage weight of 72lbs due to gross weight (1800lb) limits, and for aerobatics I'm limited to half tanks with two on board. In no loading case am I CG limited.
If I was to do things again, I would look at a lighter engine/prop combo (perhaps a composite sump and propeller, but stick to the 8.5:1 compression) and put it on a 320 engine mount. I would maybe ditch the interior primer and just fay seal everything with a modified silicone polymer (apart from the 6061T6, which I'd still prime). I guess I'll have to build another one...
Last edited by tgmillso : 07-21-2018 at 04:37 PM.