TEK Probe Data Charts Etc

[Paul Hanson]

I got 2 charts form Dr Ludek Smolik, and here are
the links to them. Draw your own conclusions from them.

http://www.eaglebrandproducts.com/TE-coefficient.JPG


http://www.eaglebrandproducts.com/Speed.JPG

As far as gusting errors, I firmly believe that the
yaw free probe (2 or 3 way that is) will give more
accurate readings during horizontal gusts. Perhaps
defining some things are in order though for this to
make sense. I never meant this to mean that the vario
will not register gusts, of course there will be a
jump up or down in the reading when there is a head
or tail gust. When that happens there is indeed a change
in total energy. If it is a head gust you can use the
additional increase in speed to gain a little hight
and vice versa. Perhaps this link will help explain
this:
http://www.eglider.org/newsarticles/totalenergycompensationinpract
ice.htm
Towards the end of this article Rudolph Brozel of ILEC
not only explains gusts adding/subtracting from total
energy, but also stresses the importance of an accurate
static system, one that does not suffer yawing errors.
This is of course going to be very different form
ship to ship.

Paul Hanson
"Do the usual, unusually well"--Len Niemi

[Martin Gregorie[_1_]]

Paul Hanson wrote:
> I got 2 charts form Dr Ludek Smolik, and here are
> the links to them. Draw your own conclusions from them.
>
> http://www.eaglebrandproducts.com/TE-coefficient.JPG
>
>
> http://www.eaglebrandproducts.com/Speed.JPG
>
Interesting stuff. I've just one question: what was the Standard probe,
IOW was it a non-swiveling Smolik probe or something else?


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

[Paul Hanson]

At 22:06 10 October 2007, Martin Gregorie wrote:
>Paul Hanson wrote:
>> I got 2 charts form Dr Ludek Smolik, and here are
>> the links to them. Draw your own conclusions from
>>them.
>>
>> http://www.eaglebrandproducts.com/TE-coefficient.JPG
>>
>>
>> http://www.eaglebrandproducts.com/Speed.JPG
>>>Interesting stuff. I've just one question: what was
>>>the Standard probe,
>IOW was it a non-swiveling Smolik probe or something
>else?
>
>
>--
>martin@ | Martin Gregorie
>gregorie. | Essex, UK
>org |

Thanks for the interest. I asked Dr Smolik your good
question and here is his reply:

Hi Paul ,

quick answer, yes the reference probe was an identical
one, more then that, it was indeed the same one,
that means 3 way and yaw free.
By the first measurement I used it as a swiveling probe
and measured the velocity and the TE-low pressure as
a function of yaw angle.
Then I taped the small air foils to the CFK main tube
and made the same measurements with such fixed probe.

In case you have not yet watched the short youtube
video of the 3-way probe in question...
http://www.youtube.com/watch?v=OpN9sYHF_yc
Hope this helps. Dr Smolik is going to start posting
soon to this group, and will be able to answer questions
quicker and better than I.

Paul Hanson
"Do the usual, unusually well"--Len Niemi

[[email protected]]

Paul, thanks for the introduction ,

probably a few words more to the "swivelling probe".
It would be not serious to claim and to preach here that such probe
can discover additional thermal.
In other words such probe is not a silver bullet !
I started the experiments with such type of probes in order to develop
a systematic better instrument for study of thermal and varios and
first I concentrated on the yawing-plane, because the free swivelling
in both planes (yaw and pitch) resulted in oscillations of the
probe.
The results with this probes show the expected improvement during the
yawing compare to the standard probe but this is not so surprising !!
At the same time the question arises: can such better reading be
converted to a better climbing etc. due to pilots action ?
For this task I have no objective measurements yet and indeed I
believe it´s a hard job to invent a meaningful experiment.
Probably our current "old-fashioned" instruments are not truly
adequate for a quick decision when the parameter which has to be
optimised calls the instantaneous sum of kinetic and potential energy
of the glider and probably also of the useable energy in the
surrounding thermal.
Who of us is fluently thinking in terms of kinetic and potential
energy ??? Just think of a moving car and its braking distance, we
learn about the quadratic velocity dependence in the school but in the
practice often first when it crashed.
I believe (and this since many years) data acquisition and computing
with data from x-y-z accelerator measurement can improve the new type
of sophisticated soaring instruments dramatically.
>From the theoretical point of view this is a natural next step in the
McCready theory and behind it. McCready theory deals with velocity
means and assumes they are more or less constant. It´s obvious that
the next dynamic improvement is to measure the forces directly taking
into account the second derivative namely the acceleration as a
function of time.

Regards Ludek