REFLECTOR: FW: Blended Winglets and intersection fillets.

[Alex Balic]

I have the 3" radius going everywhere around the fuselage too built them
exactly the same way as you described with the layer of fine bid on  top.
About the fillets- I had some of my old buddies at Texas A&M Flight Research
Laboratory help me on this- they actually have had a Velocity XLRG airframe
over there that they use for some drag testing/canard to wing airflow
studies, and they had the data- there were a couple of theses written on the
aircraft- not drag fillets specifically, so I had to sort of work through
it- as far as them needing to have high precision of form- that is not
really the case- since the reduction is  low compared to the overall drag of
the aircraft, but it would be measurable- i.e.- several knots- only time
will tell, I hope to be airborne before the end of the year. the AR5 "why is
goes so fast" tapes are still available- and I think that Mike has 4 DVD's
out now- he was able to go well over 200 mph on 65 hp, and made a big deal
about wing to fuselage and wing to wing intersections, so I figure he knows
how to reduce drag pretty well.. The blended winglet would be a best case
scenario, but I didn't want to re-engineer the wings structurally for a few
knots...

  _____  

From: reflector-bounces at tvbf.org [mailto:reflector-bounces at tvbf.org] On
Behalf Of Lawrence Epstein
Sent: Wednesday, August 03, 2011 9:18 AM
To: Velocity Aircraft Owners and Builders list
Subject: Re: REFLECTOR: FW: Blended Winglets and intersection fillets.

 

We made a 3"radius fillet at the Fuselage to strake intersection, top &
bottom. We did this using pour foam which we then sanded down with a 3" PVC
pipe and then covered with BID. 

We had some engineers at a certain Aerospace company in Mohave (thanks Ken!)
look at the prospect of doing the same thing on the wing-winglet interface
and the feeling was that the drag reduction would be minimal and the exact
shape required would necessitate extensive testing. The blended winglet
would work better here.

I will attach photos when I get access to them (maybe tonight).

Larry Epstein

On Wed, Aug 3, 2011 at 9:22 AM, Alex Balic <velocity_pilot at verizon.net>
wrote:

 

 

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