As mentioned earlier, it has been decided flush rivets
would be a nice touch for the RV-12. In order to utilize flush rivets, all the
holes on the skins will need to be dimpled as well as the corresponding holes
in the ribs underneath. However, that
change will constitute a deviation from Van’s plans and change how the aircraft
needs to be certificated.
About to start the dimpling of the vertical stabilizer
skin with the C-frame. Note the
use of the noodles (the pool toy variety) to
keep the skin level with the C-frame.
The noodles as you can see are just about the
same height as the lower die in the C-frame. The noodles
keep the skin from
becoming scratched plus allow the skins to be moved easily across the C- Frame.
So what does the title of this Blog mean? Well,
in a nut shell the RV-12, as sold by Van’s, is to be certificated as an E-LSA
(Experimental – Light Sport Aircraft). When building an E-LSA aircraft from a
kit, the builder is required to use all the parts the manufacturer supplies and
make no changes what so ever … essentially you are building an exact carbon
copy of the original Van’s RV-12. The main advantages include a relatively
short phase one flight testing requirement, professional building assistance is
permissible and annual inspections can be made by subsequent owners after
passing a 16 hour course. The big disadvantage is no changes can be made until
after the aircraft is registered and flight testing is completed.
In the case of an airplane certificated as EAB
(Experimental Amateur Built), a category that has been around since the late
1940’s, the FAA has strict restrictions. The true intent of EAB is solely for
the builders own education and recreation. Strict requirements are placed on
what is called the 51% rule … a rule that requires the builder to be able to
prove he or she did at least 51% of the work on the aircraft (this includes
taking into consideration parts prefabricated by the kit manufacturer) and the
practice of farming out parts to a professional for assembly is prohibited.
Lately, the FAA has been scrutinizing kits closer to make sure they truly comply
with the 51% rule. To Van’s credit, Van’s petitioned the FAA to have the RV-12
evaluated and it has passed the evaluation and is now on the FAA’s list of
aircraft kits that qualify under the 51% rule. The main advantage of building
the RV-12 under EAB rules is the ability for the builder to make changes to the
RV-12 during the build … so if a better radio, GPS or neat gizmo were to come
along, the builder can incorporate the new technology during the build rather
than waiting until after the build when it is much harder to make changes. The
biggest disadvantage is the phase one flight testing requirement is far longer,
typically 40 hours. The builder can apply for maintenance privileges which will
allow the builder to do the annual inspections … however subsequent owners of
the airplane must use a certified A&P mechanic to perform the annual
inspections.
For a complete tutorial on the subject of E-LSA
vs EAB there is a well written article on the Experimental Aircraft Association’s
WEB site at the following link: