How many RV-12 fuselage kits can you fit in an RV-10?

Short answer: one.

Long answer, see below...

Friday, March 1, 2013 seemed like a good enough weather day to fly the 185 nm trip from Sequim, Washington down to Aurora, Oregon to pick up an RV-12 kit for EAA chaper 430 member Trent Sommer.  Trent's first RV-12 kit had arrived in a crate that had been almost broken in half by the trucking company, so he wasn't that eager to place another bet on them.

VansRV12andMyRV10


It seemed a good omen when  we pulled into the Vans aircraft company ramp, and got the chance to park the RV-10 next to Van's own personal RV-12
KitOnCart

The RV-12 fuselage kit is normally shipped in a wooden crate that is 96" X 39" X 14" and weighs 238 pounds.

We saved the crating charge, and Vans staff put the contents that would have gone into the crate on a rolling cart.  We didn't weigh the contents-less-crate, but it was a pretty good guess that the total was less than 200 pounds -- about one back seat passenger equivalent for the RV-10, which had its back seats removed for 'aerial SUV' service.
Long pieces

The kit contains a bundle of long thin pieces that fit comfortably on top of the RV-10 center console.  The open space between firewall and baggage bulkhead in the -10 is a remarkable 109 inches, which meant that the 'slightly less than 8 foot long' bundle of pieces fit nicely, without having to remove the baggage bulkhead.
Kit in RV10

The largest pieces in the RV-12 fuselage kit are the one piece fuselage bottom skin, and the side skins.  These fit nicely with a gentle bend, extending from the floor of the baggage area forward to the front seat backs, protected from scratching the RV-10 interior by shop towels and duct tape.  The remainder of the bundled subkits and miscellaneous parts (rudder pedal weldments, steps, spar carry through assembly) all packed well into the rear seat foot wells and the flat floor of the rear cabin.
Empty cart

Cart contents consumed by RV-10.

The Van's website says "Although RVs can do many things, they won’t do everything. If you want to hurtle through the upper atmosphere at jet-like speeds, compete in advanced aerobatics or haul large dead animals out of remote places, you will need something else." 

But we can say now with certainty that if you want to haul an RV-12 fuselage kit, you won't need something else.  An RV-10 works fine and is way more fun than waiting for the truck freight guy to show up.
VanAndTrent

The icing on the cake was at departure time, when Van himself showed up and came over to take a picture of our plane and cargo.  He is shown here with builder Trent Sommer.  (I wanted to get myself in the picture but couldn't figure out how to do that.  Maybe next time. :) ).

The 185 nm back to northwestern Washington state took only an hour, and in spite of some turbulence on descent, everything stayed put in the back. 

At 8500 feet, with a 173 kt true airspeed showing on the EFIS and a 20 kt tailwind, we were covering ground at 193 knots/220 mph. 

Try that in your UPS truck!

All in all, a fine RV kind of day...