Ventus 2C Winglets

[Ventus2NZ]

Hi all

Has anyone fitted winglets to the 18M tips on a Ventus 2C?

I heard this may have been done in Europe, any information greatly
appreciated.

I would even look at getting some Maughmer winglets designed and mod
approved if I had enough interest from other Ventus 2C owners.

Alan.

[weersch[_2_]]

From the recent thread about winglets,
http://groups.google.com/group/rec.aviation.soaring/browse_thread/thread/2f97ad4d32ea29ab/f9ed5249623d8cf5?lnk=gst&q=winglets#f9ed5249623d8cf5,
I read Mark Maughmer's article "THE DESIGN OF WINGLETS FOR HIGH-
PERFORMANCE SAILPLANES".
I was flabbergasted about how little these winglets actually bring in
performance improvement, considering the amount of discussion on this
topic.
I fly in the Sierras, mostly in conditions with more than 4 kts lift.
If I read Fig. 8 and Fig.11 correctly in Mark's quoted article, with
winglets I would gain at max 0.5% L/D at 75kts cruise and 0.5% XC
speed at 4kts lift (assuming that the D2 is close enough to the V2C).
0.5% that is 0.2 point L/D improvement for the V2C @ 75 kts !!!
With my 1000 hours and 1000 flights experience, I still make enough
piloting errors like wrong turn at thermal entry, picking wrong lift
line, etc., which cause losses of a magnitude higher then these 0.5%
gains.
Based on my safety requirements, I set my polar degradation to 20%.
I have many flying buddies that achieve better flights in ships with
less performance, based on the fact that they choose to fly with less
margin and higher risk ( and are better pilots than I am).

In the conclusion of his article, Mark refers to the fact that the
difference between competition winner and no.6 is 1.5% and that
therefore the winglet gains are significant. I guess if you belong to
the "must win" competition crowd, that argument is valid.
My conclusion: for the other 90% of sailplane pilots, winglets are
irrelevant.

Of course the winglets look cool and the coolness factor is always
very important.
But for me, the V2C (and myself) already have so much coolness that I
won't need new winglets (nor hair implants on my balding head, nor a
one inch extension on my willy if I have to believe all the emails I
get)

V2C 3U

[PK]

On Mar 15, 2:12*pm, weersch > wrote:
> From the recent thread about winglets,http://groups.google.com/group/rec.aviation.soaring/browse_thread/thr...,
> I read Mark Maughmer's article "THE DESIGN OF WINGLETS FOR HIGH-
> PERFORMANCE SAILPLANES".
> I was flabbergasted about how little these winglets actually bring in
> performance improvement, considering the amount of discussion on this
> topic.
> I fly in the Sierras, mostly in conditions with more than 4 kts lift.
> If I read Fig. 8 and Fig.11 correctly in Mark's quoted article, with
> winglets I would gain at max 0.5% L/D at 75kts cruise and 0.5% XC
> speed at 4kts lift (assuming that the D2 is close enough to the V2C).
> 0.5% that is 0.2 point L/D improvement for the V2C @ 75 kts !!!
> With my 1000 hours and 1000 flights experience, I still make enough
> piloting errors like wrong turn at thermal entry, picking wrong lift
> line, etc., which cause losses of a magnitude higher then these 0.5%
> gains.
> Based on my safety requirements, I set my polar degradation to 20%.
> I have many flying buddies that achieve better flights in ships with
> less performance, based on the fact that they choose to fly with less
> margin and higher risk ( and are better pilots than I am).
>
> In the conclusion of his article, Mark refers to the fact that the
> difference between competition winner and no.6 is 1.5% and that
> therefore the winglet gains are significant. I guess if you belong to
> the "must win" competition crowd, that argument is valid.
> My conclusion: for the other 90% of sailplane pilots, winglets are
> irrelevant.
>
> Of course the winglets look cool and the coolness factor is always
> very important.
> But for me, the V2C (and myself) already have so much coolness that I
> won't need new winglets (nor hair implants on my balding head, nor a
> one inch extension on my willy if I have to believe all the emails I
> get)
>
> V2C 3U

I added. winglets to my standard class glider last year. Although I
did not make any L/D measurements before and after, therefore I'm not
sure what improvements I gained in that area. The primary reason I
added them to my already heavy glider is to improve the climb. Which
it did!
My scientific measurement was; trying to stay in a thermal with a
friend's 301 Libelle was not very possible over a year ago but it is
now!
6PK

[Tony[_5_]]

On Mar 15, 4:12*pm, weersch > wrote:
> From the recent thread about winglets,http://groups.google.com/group/rec.aviation.soaring/browse_thread/thr...,
> I read Mark Maughmer's article "THE DESIGN OF WINGLETS FOR HIGH-
> PERFORMANCE SAILPLANES".
> I was flabbergasted about how little these winglets actually bring in
> performance improvement, considering the amount of discussion on this
> topic.
> I fly in the Sierras, mostly in conditions with more than 4 kts lift.
> If I read Fig. 8 and Fig.11 correctly in Mark's quoted article, with
> winglets I would gain at max 0.5% L/D at 75kts cruise and 0.5% XC
> speed at 4kts lift (assuming that the D2 is close enough to the V2C).
> 0.5% that is 0.2 point L/D improvement for the V2C @ 75 kts !!!
> With my 1000 hours and 1000 flights experience, I still make enough
> piloting errors like wrong turn at thermal entry, picking wrong lift
> line, etc., which cause losses of a magnitude higher then these 0.5%
> gains.
> Based on my safety requirements, I set my polar degradation to 20%.
> I have many flying buddies that achieve better flights in ships with
> less performance, based on the fact that they choose to fly with less
> margin and higher risk ( and are better pilots than I am).
>
> In the conclusion of his article, Mark refers to the fact that the
> difference between competition winner and no.6 is 1.5% and that
> therefore the winglet gains are significant. I guess if you belong to
> the "must win" competition crowd, that argument is valid.
> My conclusion: for the other 90% of sailplane pilots, winglets are
> irrelevant.
>
> Of course the winglets look cool and the coolness factor is always
> very important.
> But for me, the V2C (and myself) already have so much coolness that I
> won't need new winglets (nor hair implants on my balding head, nor a
> one inch extension on my willy if I have to believe all the emails I
> get)
>
> V2C 3U

my guess is that one time somewhere some guy with winglets beat a guy
without winglets.

[Rick Walters[_2_]]

On Mar 15, 12:40*am, Ventus2NZ > wrote:
> Hi all
>
> Has anyone fitted winglets to the 18M tips on a Ventus 2C?
>
> I heard this may have been done in Europe, any information greatly
> appreciated.
>
> I would even look at getting some Maughmer winglets designed and mod
> approved if I had enough interest from other Ventus 2C owners.
>
> Alan.

Alan

The Ventus 2C 18m is not designed for winglets. It has extreme
polyhedral already
and the last short section of tip is turned up so high that a winglet
would prove worthless.
The V2CX improved the design by reducing dihedral and adding Maughmer
winglets. There is a
measureable performance improvement in the CX, but part of that is due
the new fin, rudder and
horizontal stab, and increased wingloading.

Rick Walters

[Ventus2NZ]

On Mar 16, 6:55*pm, Rick Walters > wrote:
> On Mar 15, 12:40*am, Ventus2NZ > wrote:
>
> > Hi all
>
> > Has anyone fitted winglets to the 18M tips on a Ventus 2C?
>
> > I heard this may have been done in Europe, any information greatly
> > appreciated.
>
> > I would even look at getting some Maughmer winglets designed and mod
> > approved if I had enough interest from other Ventus 2C owners.
>
> > Alan.
>
> Alan
>
> The Ventus 2C 18m is not designed for winglets. It has extreme
> polyhedral already
> and the last short section of tip is turned up so high that a winglet
> would prove worthless.
> The V2CX improved the design by reducing dihedral and adding Maughmer
> winglets. There is a
> measureable performance improvement in the CX, but part of that is due
> the new fin, rudder and
> horizontal stab, and increased wingloading.
>
> Rick Walters

Thanks for the replies.

I know the CX has a thinner aerofoil for the horizontal and vertical
tail surfaces. The outer aileron also extends right to the winglet
giving drag reduction at the tip. It is also a given that the increase
in MAUW is due to to an extra tank in the 18m tips allowing an
increase to 600kg provided the last 75kg's of ballast are carried in
the tips.
As far as the polyhedral goes, the JS1 has a very similar angle on the
last segment of the tip to reduce the toe angle to the winglet. Must
be a good reason for this, just food for thought.