SCAT Electronic News 5 January 2001 issue 528

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SCAT Electronic News 5 January 2001 issue 528


Table of Contents
=================
Good really low speed stuff - Andresen
Buy-Tech venders at the Max Men (14 rounder) - Rocket
Stepan Stefanchuk 0n-line
Low speed 'foils - Morris
Weighty A-2 ? - Thorkildsen
Articulated Bunt Animation - Limberger
Getting on line and decalage - grigsby
Join the Clubs - Bennett
Mr Bowman - bennett
Thanks

Good really low speed stuff
===========================
Author : This email address is being protected from spambots. You need JavaScript enabled to view it.

Yes it is hard to find GOOD info on Low Reynolds Number Aerodynamics.
Professor Michael Selig of UIUC has done a lot of design & testing of
airfoils in the 60,000 to 300,000 RN range, mostly for RC Sailplane
applications. It is hard to get good wind tunnel data in the low RN range
as it can be strongly influenced by turbulence and noise level in the tunnel
also the force and pressure levels are very small.

Professor Mark Drela of MIT, a former indoor record holder developed X-FOIL,
a design program for airfoils. Eppler was one of the first to have a design
program for low RN. This was probably used by Hacklinger.

The NFFS Symposia have many excellent articles on Low RN.

Hoerner has some data on low RN, and if one is into theory, Schlicting,
Boundary Layer Theory is the basis for most airfoil programs.

Indoor models have RN in the 5,000 to 10,000 range. Rubber powered record
holders use cambered plates with 3 to 10% camber.

There is also a lot of info on the NET but it is often hard to find an even
harder to filter out the valid stuff.

Forwarding any discoveries of good sites to this SEN would be appreciated.

Thanks,
H


Buy-Tech venders at the Max Men (14 rounder)
============================================
Author : This email address is being protected from spambots. You need JavaScript enabled to view it.

If any of the Buy-Tech venders plan to be at the Max Men please contact me via
e mail This email address is being protected from spambots. You need JavaScript enabled to view it..

I would like to purchase an F1-A.

I am soo ashamed!

Rocket
Akaska, USA
F1-A at the Nordic Cafe:
http://www.bristolbay.com/~rocket/RONF1A.HTM


Stepan Stefanchuk 0n-line
=========================
Author : This email address is being protected from spambots. You need JavaScript enabled to view it.


Hi Roger !
My name -Stepan Stefanchuk from Ukraine, I start with models F1B & F1G.
Many my colleagues already for a long time have the pages in Internet.
I too have decided to try and has made the page.
My address:
www.stsukr.boom.ru
If you are interested please take a look.
I shall be very glad to receive the message with the remarks or
proposals.

Best regards, Stepan.


Low speed 'foils
================
Author : This email address is being protected from spambots. You need JavaScript enabled to view it.

Regarding Professor W. Jerry Bowman's inquiry about low speed wing
performance data, the work of Dr. Michael Selig in this area in the past 15
years is the most definitive that I am aware of. His work along with
collaborators is published in several manuals: "Airfoils at Low Speed",
SoarTech #8, 1989
" Summary of Low-Speed Airfoil Data", Vol. 1, 1995
" Summary of Low-Speed Airfoil Data", Vol. 2, 199
Publisher of all of these is: SoarTech Publications
1504 N. Horseshoe Circle
Virginia Beach, VA 23451
The last address I had for Michael Selig was:
Prof. Michael Selig
Dept. of Aero. and Astro. Eng.
University of Illinois at Urbana-Champaign
306 Talbot Laboratory
104 S. Wright St.
Urbana, IL 61801-2935

Refer also to the 1995 NFFS Symposium Report in which Dr. Selig presented
an article, "Wind Tunnel Test Results of Five Free Flight Airfoils"

Gil Morris


Weighty A-2 ?
=============
Author : This email address is being protected from spambots. You need JavaScript enabled to view it.

Hi David,

3.7 Kg would be 8.16 pounds since a kilogram is a thousand grams and there
are 453.6 grams per pound.

I hope you have carbon wings at that loading but as a basic luddite type AMA
gas flyer I have no idea what is normal on a Nordic A-2 Oh I forgot I know
should say F1A glider.

Thermals and have a happy and healthy new year everyone,

Terry Thorkildsen



Articulated Bunt Animation
==========================
Author : This email address is being protected from spambots. You need JavaScript enabled to view it.


Author: René Limberger

since Allard mentioned my name in his last posting, i would finally like
to join this discussion about the future of AnimatedBuntSytems (ABS) .
(NOTE: the correct term would be: "Articulated Bunt Animation Systems"
(ABAS) but Allard likes to refer to it as "ABS")
as many of you probably know, i am flying Allard's first version of
electronic glider controllers since early 2000 and used his systems
(exclusively!) for the whole 2000 season. my overall experience, using
these systems, was very good and therefore Allard and I decided to
couple for further development.

to give you a brief impression what we are up to in the near future, let
me list our "Roadmap" for 2001 development:

* first off all, we will move to a new micro controller platform soon.
as the timer software gets more complex, the (now) old platform was too
limited in terms of memory and speed (Allard can comment on this... :-))

* in addition to a new timer hardware, we already moved from our old
Psion hardware (Revo, 3, etc.) to a brand new platform called "Compaq
iPAQ"! this device is actually a windowsCE (now "PocketPC") device
but we run "Linux"!!! on it!!! moving to a UNIX/Linux platform opens
development possibility's which are not available for Psion and Palm
platforms and gives us native development toolchain's on our UNIX
desktop workstations. the graphics and floating point performance of the

iPAQ running linux is quite remarkable and gives us a "wearable
workstation" for the flying field!

* implementing a native control application (on the iPAQ) with
GraphicalUserInterface (GUI)

* implementing a "animationGraph©" to create, delete and edit a
articulated bunt graph in real-time using the touch screen of the iPAQ

* implementing signal sampling on the iPAQ and signal reconstruction in
the timer to sample smooth curve data into a "piecewise linear" function
for servo signals

* implementing supplementary features into our application environment
(e.g. GPS software, timer software editing on the field!, etc,)


these are the main goals of our development and we hope to have
something workable in spring!
in fact, i am about to finish our first beta version of the new control
application including real-time graph editing!

Software development is time-consuming (as is hardware development)!
therefore our progress is related to the spare time. as Allard
mentioned, because of his new baby, he was not able to fly last year and
therefore he had some time to do his hardware research and development.
my time is even more limited. i will move to the USA (L.A.) this month
and i hope i will be able to continue the development as fast as
possible. my goal is to have the new systems ready for the World Champs
in october.

although there is still a lot of work to be done, the first impression
of using the new editing system is incredible and we can't wait to get
this stuff on the field!

watch out for our soon to be available project WebSite!


regards to everyone!

rene


Getting on line and decalage
============================
Subject : Re: SCAT Electronic News 4 January 2001 issue 526

Hi, Roger;

A few days back, I tried to get my freind Tom Protheroe signed up to get
the SCAT
newsletter, (he has finally gotten on line), but so far he hasn't gotten an
e-mail, so I
don't know if I did it right or not. Anyway, he's This email address is being protected from spambots. You need JavaScript enabled to view it..
Thanks.

[He's on line now - sometimes it takes me a little while to get
a rounD to it]

B.T.W., I always heard that decalage was the difference in incidence between
the
wings of a biplane, triplane, etc., even though the term has been
mis-applied by
we modelers for so long that it probably should be accepted as wing-to-stab!
Roger Grigsby




Join the club
==============
Author : This email address is being protected from spambots. You need JavaScript enabled to view it.

In a message dated 1/4/01 6:59:35 AM Pacific Standard Time,
This email address is being protected from spambots. You need JavaScript enabled to view it. writes:

<< At this time, the information I have is pretty sketchy. I am looking
for help locating information about wing performance of small wings at
low velocities. >>

Heh heh, you too, huh?

[This is because as a modeller we are always looking
for people - such a Pfof Bowman to help us with our
low speed aerodynamics]



Mr. Bowman
==========
Author : This email address is being protected from spambots. You need JavaScript enabled to view it.

Well, after my "snide aside" I did try to help Mr. Bowman more sincerely.
I sent him a link to Dr. Seelig's lowspeed airfoil website, which is
http://amber.aae.uiuc.edu/~m-selig/ I also described what I had read about
Hacklinger's airfoil tests. (He stood on a tall ladder in big arena to glide
test various indoor airfoils at various CGs.)
May Mr. Bowman really "join the club."
Mark B

Thanks
======

Thanks to F1G flyer Phil Klintworth for his donation in support of SEN.