Sinha FCS Deturbulator update

Well, here goes. I'll understand, or try to anyway, if my friends, who used
to think of me as a reasonable, level headed kind of guy, turn and run when
they see me coming down the street.

Maybe it really didn't happen. Maybe it was only a dream. Maybe it was a
calculation error or equipment failure. Maybe someone who really knows how
to test aircraft can see a flaw big enough to make it all go away. Maybe
I'll just end up with egg on my face and that will be that.

But I keep sitting here, looking at this graph, in disbelief. I built the
drag rake, constructed and calibrated the pressure sensor, flew the test
flights, crunched the numbers, plotted the graphs. I can't just write this
off as a kooky claim by someone I never heard of. You have that luxury, not
me.

Sumon, Dr. Sinha, my long time friend and hydrodynamics professor at Ole
Miss, told me a few months ago that he thought we could get 25% profile drag
reduction on my Standard Cirrus wing. "Yea, sure," I thought. "We,ll see."

He had already demonstrated 18% on an NLF0414F airfoil last year in
Starkville, MS. And we easily got the same number at some airspeeds on the
first attempt with my glider which has a very different airfoil. "That was
about it," I thought. "We lucked into the sweet spot and we probably can't
do much better than that."

Then, two days ago, last Saturday, October the 18th, Sumon thought he'd try
a little modification. I knew before landing that there was some
improvement, about 0.12 volts on the pressure sensor at 100 kts and much
smaller improvements at low speeds. (With this sensor, 1 volt is 1 inch
water gauge pressure.) When I got home and processed the data, there it was.
We had essentially doubled the drag reduction we were seeing at speeds over
70 kts and we exceeded 26% improvement at two points, one being the highest
tested speed, 100 kts. The average from 50 to 100 kts was 23.7%. We had
also corrected a low speed roll off so that we now saw basically flat drag
reductions, as a percentage of clean wing values, at all airspeeds from 40
to 100 kts.

Maybe it's a fluke, some huge error. Maybe we won't be able to repeat it
and that will be that. Or, maybe it's real.

For the full details you can take your browser to www.oxaero.com and click
the Sinha Deturbulator and Test Results links.

So there it is. Don't expect me to defend it. I'm happy to let time be the
judge.

Fire away!

In article , jeh1941
@bellsouth.net says...
So there it is. Don't expect me to defend it. I'm happy to let time be the
judge.

Fire away!

How about a picture of the device?

An explanation of how it works?

Results of polar measurements confirming the probe results?

An explanation of why you think the pressure measurements the probe
measures are directly proportional to drag when it is in only 40% of
the "flow"?

Why you didn't use little pitot tubes (instead of holes in a block) on
the drag rake, as Althaus thinks is necessary?


--
!Replace DECIMAL.POINT in my e-mail address with just a . to reply
directly

Eric Greenwell
Richland, WA (USA)

Screw that...

Where can we buy it

Al

"Eric Greenwell" wrote in message
.. .
In article , jeh1941
@bellsouth.net says...
So there it is. Don't expect me to defend it. I'm happy to let time be
the
judge.

Fire away!

How about a picture of the device?

An explanation of how it works?

Results of polar measurements confirming the probe results?

An explanation of why you think the pressure measurements the probe
measures are directly proportional to drag when it is in only 40% of
the "flow"?

Why you didn't use little pitot tubes (instead of holes in a block) on
the drag rake, as Althaus thinks is necessary?


--
!Replace DECIMAL.POINT in my e-mail address with just a . to reply
directly

Eric Greenwell
Richland, WA (USA)

You gotta spell things out for us slow kids in the back of the class. Is
the practical relevance that a 40:1 ship becomes a 40:.75? Are you moving
the polar curve, flattening it, both, other? Will it fit in a Christmas
stocking?

Brent

"Jim Hendrix" wrote in message
.. .
Well, here goes. I'll understand, or try to anyway, if my friends, who
used
to think of me as a reasonable, level headed kind of guy, turn and run
when
they see me coming down the street.

Maybe it really didn't happen. Maybe it was only a dream. Maybe it was a
calculation error or equipment failure. Maybe someone who really knows
how
to test aircraft can see a flaw big enough to make it all go away. Maybe
I'll just end up with egg on my face and that will be that.

But I keep sitting here, looking at this graph, in disbelief. I built the
drag rake, constructed and calibrated the pressure sensor, flew the test
flights, crunched the numbers, plotted the graphs. I can't just write
this
off as a kooky claim by someone I never heard of. You have that luxury,
not
me.

Sumon, Dr. Sinha, my long time friend and hydrodynamics professor at Ole
Miss, told me a few months ago that he thought we could get 25% profile
drag
reduction on my Standard Cirrus wing. "Yea, sure," I thought. "We,ll
see."

He had already demonstrated 18% on an NLF0414F airfoil last year in
Starkville, MS. And we easily got the same number at some airspeeds on
the
first attempt with my glider which has a very different airfoil. "That
was
about it," I thought. "We lucked into the sweet spot and we probably
can't
do much better than that."

Then, two days ago, last Saturday, October the 18th, Sumon thought he'd
try
a little modification. I knew before landing that there was some
improvement, about 0.12 volts on the pressure sensor at 100 kts and much
smaller improvements at low speeds. (With this sensor, 1 volt is 1 inch
water gauge pressure.) When I got home and processed the data, there it
was.
We had essentially doubled the drag reduction we were seeing at speeds
over
70 kts and we exceeded 26% improvement at two points, one being the
highest
tested speed, 100 kts. The average from 50 to 100 kts was 23.7%. We had
also corrected a low speed roll off so that we now saw basically flat drag
reductions, as a percentage of clean wing values, at all airspeeds from 40
to 100 kts.

Maybe it's a fluke, some huge error. Maybe we won't be able to repeat it
and that will be that. Or, maybe it's real.

For the full details you can take your browser to www.oxaero.com and click
the Sinha Deturbulator and Test Results links.

So there it is. Don't expect me to defend it. I'm happy to let time be
the
judge.

Fire away!

I've already stuck my neck out and estimated the effect on a 15 m glider
like mine. You can read that at www.oxaero.com, near the bottom of the page
on Dr. Sinha. In about a week I hope to have a good baseline polar for my
ship, then we will apply a full span treatment, inner panels first, and see
what we get.
JEH

"303pilot" brentUNDERSCOREsullivanATbmcDOTcom wrote in message
...
You gotta spell things out for us slow kids in the back of the class. Is
the practical relevance that a 40:1 ship becomes a 40:.75? Are you moving
the polar curve, flattening it, both, other? Will it fit in a Christmas
stocking?

Brent

How long will it last ( UV degredation, trailer rash etc )?

How's it fitted?

I sent a mail to the inventor of this system about a year ago and didn't
even get a response.

If you want to market the system you will have to spill the beans on price
etc!

Ian

Ian,
Don't know about UV yet.
It is delicate and will require TLC.
It sticks on much like turbulator tape and gap seals.
Price will be geared to performance.
Jim

"tango4" wrote in message
...
How long will it last ( UV degredation, trailer rash etc )?

How's it fitted?

I sent a mail to the inventor of this system about a year ago and didn't
even get a response.

If you want to market the system you will have to spill the beans on price
etc!

Ian

Ahhhh

Nothing to do with the cost of production so much as what the market will
stand? I see that the US military have a vested interest in the patents
having supplied funding for the development. What percentage will they get
from sales?

Could be interesting. The US government may prohibit the sale of this item
to outside countries under some 'export of technology' legislation.

Ian

Man, the soaring season is a long way off!

"Jim Hendrix" wrote in message
. ..
Ian,
Don't know about UV yet.
It is delicate and will require TLC.
It sticks on much like turbulator tape and gap seals.
Price will be geared to performance.
Jim

"tango4" wrote in message
...
How long will it last ( UV degredation, trailer rash etc )?

How's it fitted?

I sent a mail to the inventor of this system about a year ago and didn't
even get a response.

If you want to market the system you will have to spill the beans on
price
etc!

Ian

"tango4" s comments read:

Man, the soaring season is a long way off!

A true statement there never was!

At the rate that u.r.a.s.b is going there won't be any sane pilots
left come spring ... quite funny though ;-)
--
Tim - ASW20CL "20"

At 06:54 22 October 2003, Tango4 wrote:
Ahhhh

Nothing to do with the cost of production so much as
what the market will
stand? I see that the US military have a vested interest
in the patents
having supplied funding for the development. What percentage
will they get
from sales?

Could be interesting. The US government may prohibit
the sale of this item
to outside countries under some 'export of technology'
legislation.


If that were the case, the FAI should ban it from international
competitions and world record claims.