How do I legallly install winglets on a standard airworthiness certificate?

On Nov 22, 3:16*pm, Scott wrote:
On 11-22-2010 13:36, JJ Sinclair wrote:





On Nov 21, 5:49 am, *wrote:
Scott,

The 337 form can be sent in before the work begins. *This allows for
approval/disapproval before a saw is taken to the airplane. *I imagine
you will have to hire a DER (designated engineering representative) to
do an engineering analysis to accompany the 337. *Harold Kasola is
very easy to work with and has Kasola Engineering in Albany, GA. *A
call to him would be worth the effort. *Having just certified a club
glider in experimental (last week), I can tell you it took a few days
and a trip to the FSDO.

No inspector is going to sign a 337 before the work is done and DAR/
DER's aren't cheap. I paid $750.00 for an airworthiness-for-export and
the guy wasn't here more than 30 minutes.
JJ

And I'm still having a hard time wrapping myself around the notion that
the FAA would be happy to change an aircraft airworthiness certificate
from standard to experimental for such a "small" change to the aircraft
and then turn over maintenance to the owner and just have an A&P sign
off a condition inspection yearly. *Plus, I still think 337s are not
used to place an aircraft into the experimental category. *For example,
a 337 (or STC) would be needed (I believe) to recover the wings on a
Cessna 140 that was originally covered with Grade A cotton when built
and certified and you recovered them with Stits.- Hide quoted text -

- Show quoted text -

Scott,
In order to modify a ship in standard category you need a 337 and your
inspector will need an approved method usually an STC. There is no
approved method for adding winglets to your Cirrus and an DAR or EAD
or FAA engineering will still need approved data.
The other way to add winglets to your Cirrus is to go down to your
FSDO and tell them you would like to add winglets, but the factory
doesn't provide this option. Request they change your registration to
experimental. Once your in experimental category, the winglets may be
added with a log book entry from an A&P. I recommend you have the work
done at a certified repair shop because improperly installed winglets
can change the flight characteristics and lead to big
trouble................I remember a guy that added his own home brew
winglets and the ship was the better part of uncontrollable! The only
way he was able to maintain control was to keep the speed above 80. He
was forced to land doing 80 also.
Hope this helps,
JJ