Ka-6 TE Probe

My Ka-6 currently has no TE compensation for the Vario. At one time it
had a Scheumann compensator installed, but this nifty box didn't come
with the glider. So now I am looking to install a TE probe.

Does anyone have any recent experience in installing one?

I was initially thinking about the tail mounted type (probably the
ILEC with the socket), but the fuselage mount type would be a much
simpler install. Is the tail mounted probe worth the extra effort in
install over the fuselage type?

Does anyone have a Schuemann compensator gathering dust they want to
sell?

thanks

Pete

On Aug 28, 9:24*am, vontresc wrote:
My Ka-6 currently has no TE compensation for the Vario. At one time it
had a Scheumann compensator installed, but this nifty box didn't come
with the glider. So now I am looking to install a TE probe.

Does anyone have any recent experience in installing one?

I was initially thinking about the tail mounted type (probably the
ILEC with the socket), but the fuselage mount type would be a much
simpler install. Is the tail mounted probe worth the extra effort in
install over the fuselage type?

Does anyone have a Schuemann compensator gathering dust they want to
sell?

thanks

Pete

Dick Johnson would probably have told you the fin mount type are not
necessary. See his article on making simple but effective fueslage
mount TE probes in Soaring Magazine. Sorry I don't recall the issue,
think it was a in the last few years. I'd go the path of least work,
kind of hard to justify worrying about state of the art TE
compensation for a Ka-6.

Darryl

Darryl Ramm wrote:
I'd go the path of least work,
kind of hard to justify worrying about state of the art TE
compensation for a Ka-6.

Last I looked, efficiently finding and centering thermals is even more
important in a Ka-6 than it might be in, say, an ASH-26E.

The Johnson article was in the June 2005 issue of Soaring...

Marc

On Aug 28, 10:00*am, Marc Ramsey wrote:
Darryl Ramm wrote:
I'd go the path of least work,
kind of hard to justify worrying about state of the art TE
compensation for a Ka-6.

Last I looked, efficiently finding and centering thermals is even more
important in a Ka-6 than it might be in, say, an ASH-26E.

The Johnson article was in the June 2005 issue of Soaring...

Marc

Marc, that was not the point (and you know it :-)). having the T.E.
compensation work over a wide dynamic range makes T.E. compensation
less of a challenge given the performance of older gliders like this.
That is not a slight on the Ka-6. I'd put in an easier to install
fuselage mounted probe and spend that extra money you saved buying
beers/dinner for your tow pilot.

BTW I center iron thermals perfectly in the ASH-26E.


Darryl

Darryl Ramm wrote:
On Aug 28, 10:00 am, Marc Ramsey wrote:
Darryl Ramm wrote:
I'd go the path of least work,
kind of hard to justify worrying about state of the art TE
compensation for a Ka-6.
Last I looked, efficiently finding and centering thermals is even more
important in a Ka-6 than it might be in, say, an ASH-26E.

The Johnson article was in the June 2005 issue of Soaring...

Marc

Marc, that was not the point (and you know it :-)). having the T.E.
compensation work over a wide dynamic range makes T.E. compensation
less of a challenge given the performance of older gliders like this.
That is not a slight on the Ka-6. I'd put in an easier to install
fuselage mounted probe and spend that extra money you saved buying
beers/dinner for your tow pilot.

BTW I center iron thermals perfectly in the ASH-26E.

I would assume so 8^)

Marc Ramsey wrote:
Darryl Ramm wrote:
I'd go the path of least work,
kind of hard to justify worrying about state of the art TE
compensation for a Ka-6.

Last I looked, efficiently finding and centering thermals is even more
important in a Ka-6 than it might be in, say, an ASH-26E.

My experience in both those gliders is the Ka-6e doesn't need as good a
TE as the 26E, because the cruise speed is much lower. Pulling up from
65 knots isn't as demanding as pulling up from 85 knots.

Once in the thermal, the variations in speed are small and don't affect
the vario reading enough to see the difference between a fin mount or a
fuselage mount. This is particularly true because a 2 or 3 knot
variation at the 50 knot thermalling speed of the 26E is over twice the
altitude change that 2 or 3 knots produces at the Ka-6's 33 knot
thermalling speed.

And finally, my distant recollection of flying the Ka-6e is it's 5 light
wing loading (lb/sqft vs 8.5 lb/sqft) and low thermalling speed made it
easier to find/feel/sense and center thermals.

So, I'd suggest trying the very easiest thing first: a TE probe mounted
on the removable turtledeck, probably towards the rear it. If it works,
great; if not, very little effort wasted.

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly

* Updated! "Transponders in Sailplanes" http://tinyurl.com/y739x4
* New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more

* "A Guide to Self-launching Sailplane Operation" at www.motorglider.org

Eric Greenwell wrote:


And finally, my distant recollection of flying the Ka-6e is it's 5 light
wing loading (lb/sqft vs 8.5 lb/sqft)

Well, that went badly: it's 5 lb/sqft vs 8.5 lb/sqft!

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly

* Updated! "Transponders in Sailplanes" http://tinyurl.com/y739x4
* New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more

* "A Guide to Self-launching Sailplane Operation" at www.motorglider.org

Eric wrote.......
So, I'd suggest trying the very easiest thing first: a TE probe mounted
on the removable turtledeck, probably towards the rear it. If it works,
great; if not, very little effort wasted.

Yeah, what he said......................I used a vertical TE probe on
my Duster a hundred years ago and it worked as good as I did. If your
intimidated my the thought of drilling and stringing tubes, go the
easy way, it can be mounted forward of the canopy where there isn't
any interference with the wings. Wings & Wheels sells them and I
believe the top bent portion in set to be vertical with the ship set
in flying position (W&B level)
JJ

Like JJ said

If you want to do it easy and perfectly adequate as well, install a
nearly vertical tube ahead of the canopy near the bulkhead ahead of the
instrument panel (above the static buttons on the side of the fuselage).
I would suggest angling it slightly forward at the top so that the
tube is about perpendicular to the upwash induced by the wing. The top
of the tube could be about 6-8" outside the fuselage. Plug the top end
and put the hole or holes or slots in the back of the tube as drirected
from your favorite article by Oran Nicks' (Nicks tube) or Dick Johnson
or insert other favorite name here. The plumbing is short, easy to
do, and will give a reading that is well compensated. Our club Ka6CR
has one like this and it works well.

I would not suggest over the wing in the turtledeck, since it could
require uncoupling and coupling the pressure tube with some regularity
and it would be easy to damage when the turtledeck is off.

The position on top of the fuselage near the trailing edge of the wing,
however is not a bad one. The flow around the wing is nearly back to a
freestream static condition at the trailing edge and the flow had better
be attached while cruising or thermalling or there are other problems.
If one flys slow enough to separate the flow there, the inboard wing is
already stalled and that's flying too slow.

...... Neal

JJ Sinclair wrote:
Eric wrote.......

So, I'd suggest trying the very easiest thing first: a TE probe mounted
on the removable turtledeck, probably towards the rear it. If it works,
great; if not, very little effort wasted.


Yeah, what he said......................I used a vertical TE probe on
my Duster a hundred years ago and it worked as good as I did. If your
intimidated my the thought of drilling and stringing tubes, go the
easy way, it can be mounted forward of the canopy where there isn't
any interference with the wings. Wings & Wheels sells them and I
believe the top bent portion in set to be vertical with the ship set
in flying position (W&B level)
JJ

On Aug 28, 12:24*pm, vontresc wrote:
My Ka-6 currently has no TE compensation for the Vario. At one time it
had a Scheumann compensator installed, but this nifty box didn't come
with the glider. So now I am looking to install a TE probe.

Does anyone have any recent experience in installing one?

I was initially thinking about the tail mounted type (probably the
ILEC with the socket), but the fuselage mount type would be a much
simpler install. Is the tail mounted probe worth the extra effort in
install over the fuselage type?

Does anyone have a Schuemann compensator gathering dust they want to
sell?

thanks

Pete

Take the time to put it in the fin. This keeps it out of the wing
root wash and will make
the variometer reflect what the glider is doing instead of how it
responds to effect of gusts
on wing root.
It may be easier than trying to work as far behing wing root as it
should go.
Just put one in a K-21 fin and it is MUCH better than aft fuselage.
Good Luck
UH