SEN 681 - 6 Mar 2002

SCAT Electronic News 6 march 2002 issue 681

Table of Contents
More bent Benedek - Mathews
Oleg's Foils ? - Mathews
F1E and GPS - Scott
FOR SALE: New Stamov Electronic F1H with RC DT function - Mac the Bigot
No disgraceful stall here - Woodhouse
Correction to Nor Cal FF Champs - Terzian
Totally Left - Mosely
left turning - Brooks
Safety my Donkey - Parker
FAI Meeting March 22 2002 - Segrave

More bent Benedek
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Subject : Re: SCAT Electronic News 2 March 2002 issue 680

> B-6456f and long runs
> ======================
> Perhaps the trickiness of the section is due to using high
> camber AS WELL As a rearwards point of maximum mean camber.

The whole point of the Benedek/Jedelsky analysis of low reynolds number
sections, was to ignore the mean camber completely. The idea was to treat
the upper surface camber and the lower surface camber separately. So I
believe that whether a section has a rearwards or forwards mean camber
is irrelevant.

Reviewing the 6456-f, the section has a maximum upper surface camber of
9.0% at 30%. This is farther forward than some, but not out of the
ordinary. The maximum undercamber is 4.5% at 60% chord. This is fairly
far back. I could not find any of the Gard sections with the same
undercamber. While the Gard 8910 also has 4.5% undercamber, it occurrs at
50%, and not 60%. The maximum thickness of the 6456-f is 6.5% at 20%
chord. Now this is farther forward than many other sections. I also note
the lack of Phillips entry, and the steep curvature in the front 20%. It
has always been my experience that a lack of Phillips entry, and a steep
intitial curvature is "less stable" than a section with more Phillips, and
a flatter intial curvature. Perhaps these features have more to do with
the alleged "trickiness" of the section than the flatter top and the rear

The 9.0% top camber is not what I would call "high camber" for F1B, at least
for a root section. Although 9.0% is about the maximum that I would use on
an F1B. For F1A, a maxiumum of 10% seems possible (perhaps even a bit
higher?), while for F1G I would think that no more than 8% is advisable.
Reynolds number effect and all that.

As for long prop runs for F1B, I seem to recall that we have been down that
path before? Perhaps Mike Segrave remembers Ben Tarnovski's models? If I
recall, he used a very long prop run for many years. I was always underwhelmed
by this approach. I also remember many of the french aeromodellers using
extreme prop runs some years ago. Then there was John Gard with his
Monarchs. In the early 90's Walt Ghio was pushing the prop run on his models
to over 70 seconds (IIRC). He told me that he thought the long run models got
higher in thermals, and that might be an advantage for long fly-off
flights. Of course this assumes that you actually nail the thermal! It always
seemed to me that the long run models looked good in thermals, but looked
horrible in mediocre or even poor air, while the shorter run models might
still attain sufficient altitude in mediocre air to still max. I can never
get the image out of my mind of one of Ben's models chugging away for what
seemed like an eternity in a still evening, only to barely make less than
towline height. Give me altitude any day!

Tony Mathews

Oleg's Foils ?
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Does anyone have any details of Kulakovsky's F1B that they could send me? I am
particularily interested in the wing and stab sections (of course!). I would
appreciate any help on this matter.


Tony Mathews

Bear Cup
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1 Valo Jari FIN 900+300 327 - - 1527
2 Findahl Per SWE 900+300 294 - - 1494
3 Varhos Denits SWE 900+300 258 - - 1458
4 Kulmakko Kimmo FIN 900+300 210 - - 1410
5 Leino Laura FIN 900+300 184 - - 1384
6 Tahkapaa Heikki FIN 900+284 - - - 1184
7 Tchop Victor UKR 900+278 - - - 1178
8 Varuskivi Vesa FIN 900+273 - - - 1173
9 Isotalo Tommi FIN 900+270 - - - 1170
10 Poliayev Valeri RUS 900+254 - - - 1154
11 Lepp Andres EST 900+251 - - - 1151
12 Kuikka Petri FIN 174 180 180 180 180 894
13 Pajunen Timo FIN 180 180 180 180 172 892
14 Heikkinen Juha FIN 163 180 180 180 180 883
15 Koivula Kalle FIN 160 180 180 180 180 880
16 Kutvonen Lauri jr1 FIN 180 180 180 171 163 874
17 Rahkala Pekka FIN 180 180 180 153 180 873
18 Laaksonen Jori FIN 180 160 180 180 168 868
19 Lihtamo Matti FIN 144 180 180 180 180 864
20 Kuningas Juhani FIN 144 180 176 180 180 860
21 Sillgren Jukka FIN 180 128 180 180 180 848
22 Tuisku Kari FIN 117 180 180 180 180 837
23 Runnari Valve FIN 115 163 180 180 180 818
24 Henrikson Kim FIN 180 85 180 180 180 805
25 Kiiskinen Tuomo jr2 FIN 180 137 118 180 180 795
26 Ronkanen Pekka FIN 88 166 174 180 180 788
27 Kordemets Anti EST 53 180 180 180 180 773
28 Munnukka Niilo FIN 153 144 124 167 180 768
29 Lehtovirta Joonajr3 FIN 137 160 153 153 165 768
30 Parna Ardo EST 180 180 64 180 152 756
31 Selgoja Ants EST 67 179 150 180 180 756
32 Kutvonen Ari FIN 180 180 180 18 180 738
33 Kiljunen Harri FIN 147 125 101 180 180 733
34 Malm Jouni jr4 FIN 118 125 142 180 126 691
35 Vuks Virko jr5 EST 103 96 151 125 145 620
36 Ahmetov Eldar jr6 EST 131 112 129 116 120 608
37 Puju Enno EST 158 117 39 157 58 529
38 Auvaart Priit jr7 EST 110 94 119 102 28 453
49 Runnari Juho jr8 FIN 16 32 - - - 48
40 Taponen Teemu jr9 FIN - - - - 12 12

1 Razko Vadims LAT 900+300 248 - - 1448
2 Kutvonen Ari FIN 900+300 133 - - 1333
3 Sarpila Teppo FIN 900+255 - - - 1155
4 Girsus Laurynas LIT 900+244 257 - - 1144
5 Linkosalo Tapio FIN 900+244 219 - - 1144
6 Waltonen Yrjoe FIN 900+240 - - - 1140
7 Isotalo Juhani FIN 900+225 - - - 1125
8 Rosonoks Viktors LAT 900+164 - - - 1064
9 Soederling Magnus SWE 900+ 83 - - - 983
10 Isotalo Janne FIN 179 180 180 180 180 899
11 Kiiskinen Markku FIN 172 180 180 180 180 892
12 Rolands Markus LIT 180 180 180 180 160 880
13 Solodov Maxim RUS 154 180 180 180 180 874
14 Harjo Indrek EST 180 180 180 180 152 872
15 Posa Riku FIN 180 180 180 150 180 870
16 Mantere Antti FIN 170 113 180 180 180 823
17 Kilpelainen Ossi FIN 137 125 180 180 180 802
18 Henrikson Jari FIN 121 165 175 19 5 485
19 Holm Thomas FIN 180 178 85 - - 443
20 Pakarinen Teuvo FIN 102 - 117 126 75 420

1 Naaber Raimond EST 900+276 - - - 1176
2 Kuukka Kaarle FIN 900+264 - - - 1164
3 Roots Jyri EST 180 180 180 180 66 786
4 Lindgren Kari FIN 102 - - - - 102

1 Mihkel Joala EST 123 170 180 169 180 822
2 Kutvonen Lauri FIN 164 150 180 180 144 818
3 Lehtovirta Joona FIN 130 153 165 180 140 768
4 Kiiskinen Tuomo FIN 72 155 175 180 180 762
5 Taponen Teemu FIN 127 140 129 149 180 725
6 Jarvinen Mauri FIN 145 107 143 118 137 650
7 Runnari Juho FIN 58 100 76 120 174 528
8 Penttila Topi FIN 125 72 104 118 34 453
9 Airaksinen Henry FIN 35 73 142 25 74 349

F1E and GPS
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F1E and GPS.

If satellite transmissions can be harnessed via GPS for steering
purposes in the F1E event, as a couple of contributors seem to think,
the possibilities are boundless.

I can envisage an F1E model being programmed to climb away from the
launch point until preset distance out and height are reached, then
incidence adjustments maintain this position. As conditions vary, and
changes in altitude are sensed, corrections are fed smoothly and
continuously to the flying surfaces. Any deviation from the preset
co-ordinates - whether left, right, fore, aft, up or down - are
compensated for automatically by the on-board unit, until such time as
another maximum is made. At this time, the model obediently follows its
programming and uses its continuous stream of satellite guidance signals
to gently descend and land on the launch co-ordinates.

Another glorious flight, and with none of those little impediments the
other, less sophisticated, flyers are still experiencing. No more errant
models, no more retrieves, no more careful study of the local
conditions, no more sense of achievement, no more skill. I am in full
agreement with the sentiments expressed by Steve Philpott regarding the
nature of F1E and the likely effects of so called "development". =
28 Feb, #679).

Besides, why re-invent the wheel? The type of model that would result
from the mating GPS and F1E already exists - it's called a radio
controlled slope soarer. Why not simply fly one of these if you need to
get that "control" fix?

Bernard Scott.

[It appears to me that the fundemental difference between Radio Control and
other forms of flight control that are
being discussed is the matter of human intervention. With Radio Control
the sportsman is flying the airplane. He is the person who judges the
the situation and command the airplane. That is on of the appeals
of Radio Control. What is being proposed with F1E and GPS and the like
is that the sportman predetermines the actions before take off.
We do that already with Free Flight airplanes with the warps and other
built in aerodymanic setting, the power adjustments and
automatic surfaces of various kinds. Sometimes these cause our
airplane to fly perfectly, sometines they malfunction upset the
intended flight and other times the flight is upset by natural
events such as thermals, down drfats, turbulenence, wind, ...
The challengs of Free Flight is to overcome all of those
obstacles to produces the perfect flight.

This discussion is similar to the one we had some years back about
the use of electronics in F1A, B and C. There is a school of thought
of which Bernard Scott appears to be a memember that regards anything
electronic as bad and in fact some form of Magic [probably Black!].
By having this on board Magic a max is assured so there will be no
more comptetion or that the Magic will clearly out weight the
aerodymanic qualities of the airplane and abilties of
the sportsman. As someone who has been involved with on
board Magic for about 10 years I can assure you that this
is clearly not the case as while I have not had any catastrphoic
system failures, my on board Magic has not overcome
the aero dymanic qualities and abilities of sportsmen
such as Walt hgio, Oleg Kulakovsky, Alexander Andriukov, and
many others.

I am also painfully aware that it is impossible to convince anyone
of the difficulty of making Magic. During the last round on this subject
I do not belive that I convinced anyone and that I think the only
person who did was Matt Gewain. I believe that succeeded in convicing one
person that Magic is hard and not assurance of an instant max. However
Matt was discouraged by the offical US position in restricting
on board electronics and the associated noise that he stopped
flying F1A. Clearly the Luddite objective was achieved when
they discouraged one of the top F1A innovators, a World Champion,
many time team member from partitpating in his event. ]

FOR SALE: New Stamov Electronic F1H with RC DT function
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FOR SALE: New Stamov Electronic F1H with RC DT function, Brand new, was
flown a few time by Victor and myself on the day of delivery, it's trimmed
and ready to go, state of the art! I'm upgrading to an M&K Mechanical F1H so
I don't need this one. I paid $1,050 for it this last October. Also
includes the RC DT control box and the cable from the Palm Pilot to the
model. Be kind and only make reasonable offers!

Jon Davis

No disgraceful stall here

Interesting in that I had and have mentioned the stalling with the Benedek.
I tried that Gard section and obviously pushed it too hard and managed the
odd stall down with that as well. So that I abandoned it. Currently I use
on my best performing model the B-6356-b thinned and flatened towards the
tip. This section has never disgraced itself by stalling dowmn.

Michael J Woodhouse, Norwich, UK
All mail to: -

Correction to Nor Cal FF Champs
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The only glaring error I noticed in SEN was that the One Design Event for
the T-Bird 1/2A gas design is that the T.D. .049 and .051 engines are NOT
allowed since this is a Nostalgia event. The typo must have been a carryover
from last year when we sponsored the Space Rod by the late Vic Cunnyngham
(which was a design that followed the Nostalgia period cutoff date).

Fred T.

Totally Left
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> Maybe that's
why Jim Brooks' F1Bs go left (I don't think he uses left-handed props).

Yes, he does. Jim's lefthanded....

left turning
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My props are sinistral, thier sinistrogyrations often producing =
sinistrorse results: were it otherwise the outcome might well be sinistrous=

Safety my Donkey
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The French are really missing the boat on the safety issue if they don't
include Fuzevev's folder in the proposed ban. That thing is one "Serious
Lawn Dart" when it doesn't unfold, as experienced several times by the
fliers at the 99 World Champs in Israel. And how about that nasty Tan II
rubber; that stuff really scares me when their breaking motors all around me
on the flight line! The CIAM will loose all credibility if they touch the
gear this late in the game.


FAI Meeting March 22 2002
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You are right to suspect whhat may happen t this meeting, if some of the
following is taken onto account. First, the F1C flyoff at the 95 World
Champs in Domsod,Hungary. At the end of the days flying, there were 5 left
to dispute to 10 minute round early the next morning, 2 USA men,Archer and
Morris (who I thought has the best plane there). 2 Chinese and one European,
Boutillier. As I ate my evening meal, I began to wonder how they were going
to make the European win as he did not seems to have an outstanding ship, at
least not noticeably better than the others and certainly not better than
Morris's. Next day, those who had kept time on the previos days were
astounded to learn that ONLY HUNGARIAN timekeepers would be used - the first
hint? The Chinese led off but had a bad pullout. Next, Morris but 2 or 3
shallow stalls ended his hopes. The European and the chinese went next but
neither looked like the winner. Finally Archer, straightup,perfect bunt with
no height lost and floated away. We all waited for the result. As times came
in Pierre Chaussebourg infiltrated into the proceedings. This was allowable
for he was a member of the Jury - but ONLY AS A MEMBER OF THE JURY. Andras
REE the contest director then allowed Chaussebourg to go to the FOUR
timekeepers of Archer's flight, record the times on a slip of paper and then
tell REE what Archer's time was. Remember, he waas only there as a member of
the Jury and NO OTHER FUNCTION other thhan observer. What's even more
distressing i that REE did go and verify Archers times with the timekeepers.
Meanwhile ship had sailed away over the trees at the side of the field
landing at around 11 minutes which would have made him an easy winner. As it
was, such were the times recorded by Chaussebourg that Archer did not veen
get a place!!! only 4th. 2 years later, at Sazena in the final flyoff in
F1C. the best climb was by Bob Gutai but guess what, he got 2 repeat
OVERRUNS and did not place anywhere the top. Doug Galbreath has said a
number of tmes that he gets screwed every time he goes to Europe. Is is
because all three are Americans? It has often been said the World Champs are
really a European Champs to which the USA Canada Australia and Japan and
China attend. There seems to be some trith in this, it seems. On reading the
above, I see that I have written ".. that Ree did go and verify". That
should read "..that REE did NOT go and v erify". QED Mike S

Roger Morrell