Lowering Stall

[Dick]

Just for discussion, what opinions are there for an individual lowering the
stall speed of an existing wing considering constructability and cost?

I remember there was some leading edge profile modification studies done
years ago but can't see that as a practical approach for an individual.

Thinking about how to add sailplane-type upper surface spoilers, WW2
fighters underwing dive brakes, etc.

Dick

[Jan Carlsson]

Dick,
Spoilers on gliders kill lift and add drag, so it does really not lower the
stall speed.

A modified leading edge will, it can be made with a ad-on like it is made on
Cessnas and others.

One simple way to gain some is to seal the hinge line and the junktion
between wing and fuselage.

VG's = vortex generators is another way to go.

Jan Carlsson
www.jcpropellerdesign.com


> Just for discussion, what opinions are there for an individual lowering
the
> stall speed of an existing wing considering constructability and cost?
>
> I remember there was some leading edge profile modification studies done
> years ago but can't see that as a practical approach for an individual.
>
> Thinking about how to add sailplane-type upper surface spoilers, WW2
> fighters underwing dive brakes, etc.
>
> Dick
>
>

[ET]

"Dick" > wrote in
m:

> Just for discussion, what opinions are there for an individual
> lowering the stall speed of an existing wing considering
> constructability and cost?
>
> I remember there was some leading edge profile modification studies
> done years ago but can't see that as a practical approach for an
> individual.
>
> Thinking about how to add sailplane-type upper surface spoilers, WW2
> fighters underwing dive brakes, etc.
>
> Dick
>
>

Are you wanting to slide your plane into the sport pilot rule perhaps???



--
ET >:)


"A common mistake people make when trying to design something
completely foolproof is to underestimate the ingenuity of complete
fools."---- Douglas Adams

[Dick]

excellent guess. you're correct. I have two incomplete projects that might
be convertable to LSA (Light sport Aircraft) definition and use the Sport
Pilot license upon losing my medical/PPL.

[ET]

"Dick" > wrote in
om:

> excellent guess. you're correct. I have two incomplete projects that
> might be convertable to LSA (Light sport Aircraft) definition and use
> the Sport Pilot license upon losing my medical/PPL.
>
>
>

I had a conversation with one of the folks a Jabiru, they have 1 airplane
that becomes 4 airplanes with the a change of wing, taking out 2 seats,
and/or just putting on the placard "not to exceed 1250lbs Gross" (for a
sportplane) even though it's the exact same plane that can haul 1540lbs
Gross.... watchout for FAA guys bearing scales eh?? <heh>



Sonex is talking about their 150-170mph plane, just change the prop to a
"climb" prop, it's now sport plane legal.

--
ET >:)


"A common mistake people make when trying to design something
completely foolproof is to underestimate the ingenuity of complete
fools."---- Douglas Adams

[Paul Lee]

Have you looked at those vortex generator tabs placed on top of
the wing. Very negligible top end decrease. They come in a kit
and are easy to apply. Users claim 5-10 kt decrease in stall.

"Dick" > wrote in message >...
> Just for discussion, what opinions are there for an individual lowering the
> stall speed of an existing wing considering constructability and cost?
>
> I remember there was some leading edge profile modification studies done
> years ago but can't see that as a practical approach for an individual.
>
> Thinking about how to add sailplane-type upper surface spoilers, WW2
> fighters underwing dive brakes, etc.
>
> Dick

[Dick]

I'll need to find a site. Sounds interesting. Thanks.
"Paul Lee" > wrote in message
om...
> Have you looked at those vortex generator tabs placed on top of
> the wing. Very negligible top end decrease. They come in a kit
> and are easy to apply. Users claim 5-10 kt decrease in stall.
>
> "Dick" > wrote in message
>...
> > Just for discussion, what opinions are there for an individual lowering
the
> > stall speed of an existing wing considering constructability and cost?
> >
> > I remember there was some leading edge profile modification studies done
> > years ago but can't see that as a practical approach for an individual.
> >
> > Thinking about how to add sailplane-type upper surface spoilers, WW2
> > fighters underwing dive brakes, etc.
> >
> > Dick
>

[Gilan]

Most of the people I have talked with that have VGs on their wings get
around a 10% improvement on stall speeds. 50 becomes 45 you get the
picture.

--
Have a good day and stay out of the trees!
See ya on Sport Aircraft group
http://groups.yahoo.com/group/Sport_Aircraft/