Many potential RV-12 builders don’t realize that they have a choice in how to build and certify their aircraft. The two choices for the RV-12/RV-12iS are Experimental – Light Sport Aircraft (E-LSA) and Experimental – Amateur Built (E-AB). 

E-LSA — Van’s has designed the RV-12 (and RV-12iS) specifically to conform to the E-LSA category. If the builder opts to certify it E-LSA he/she must build the plane EXACTLY as the plans specify, no deviations or modifications whatsoever. In exchange for that restriction the “51% rule” that governs E-AB aircraft does not apply and the manufacturer can provide a more highly manufactured kit that might not comply with the “51% rule” thus reducing build time. 

E-AB — Van’s wisely applied for and received NKET approval early on so that the RV-12 is “pre-approved” for certification into the E-AB category just like all of the other RV models. In fact when Van himself built an RV-12 right when they were being introduced he certified it as an E-AB though I don’t think he deviated from the plans in any way. This option has always been available to RV-12 builders but relatively few have utilized it.

In the time since the RV-12 was introduced it seems that Van’s has encouraged and pushed the E-LSA path. I’m sure it reduces their support burden when builders follow the plans exactly. Van’s cannot provide support for any builder mods though apparently builders commonly ask. 

Having built two E-AB aircraft I’m a bit spoiled by the flexibility the builder has in configuring the aircraft. That, and consistent with one of my reasons for this plane — that I need it to be IFR equipped and legal for IFR flight — I will build and certify mine as an E-AB. Though E-LSA aircraft can be used for instrument training any LSA category may not operate in actual IMC. And there are certain mods I want to make, fairly small actually, that I’m just not willing to compromise on.  

In summary, I will be building/certifying as E-AB and my initially intended deviations from E-LSA are:

• A heated pitot under wing, likely omit the standard standard pitot system in the spinner.
• Likely customize the instrument panel center section to include an IFR navigator.
• Install LEMO headphone jacks in addition to the standard jacks for ship’s powered ANR headsets. (can’t believe these aren’t standard!) 
• Use Skybolt fasteners for the cowling perimeter
• Various other small deviations, none structural of course.

I plan to document it all here, check back whenever you’re curious and let’s see how it turns out!