wrote:
OxAero wrote:

After three years of working to configure Sumon Sinha's deturbulator
tapes for my Standard Cirrus, we finally brought it to Caddo Mills for
one of those Johnson flight test evaluations. He and Jeff Baird flew
it six times with those shiny silver strips on the wings, then three
times without. What did they learn? Come to the Convention in Memphis
to find out. Dick, as usual, will tell it straight. Will you laugh?
Will you be dumbfounded? Will you believe?

Jim Hendrix


It is nice, but will it work on something other than an antique glider?
Is it better than just putting on zig-zag tape? The tests are
interesting, but mean nothing without direct comparisons to standard
treatments and on a modern airfoil.

You know that sounds good - Now I can say:

In September I did my Gold distance and Diamond goal(316Km and 322Km) in an
antique glider.

Somehow sounds quite an achievement.

For what it is worth the lift was strong, and even 1:36 was more than enough.
Now for that 500km - suspect I will have to be a little more courageous for that
one.

The point is well taken that the Cirrus has a rather thick "first generation
glass" profile. It does produce both top and bottom separation bubbles, and
these tend to move, making the exercise of removing them more difficult. This is
why you will seldom see a std Cirrus with deturbulator tape - it does not appear
to work very well except at specific speeds. I agree it may be harder to show
large improvements on better behaved airfoils, but I suspect the old Wortman is
a good place to find out if it works in difficult conditions. I presume Dr Sinha
had a reason for choosing it beyond availability.