SEN 871 - 1 May 2004

SCAT Electronic news 1 May 2004 issue 871


Table of Contnets
=================
Spring Cup Seguin Results - Parker
NZ World Cup Events 2004 Plus other events
Patching Ikorex - Ulm
Patching Icrex - Bradley
Seelig Glider Timer: - Stalick
"Leeper"? simple answer...
Power Book [ NFFS not Apple !] - Stalick
SAFETY ALERT: LI-POLY BATTERIES
FAI Qualifier... - Shailor
A Few Seeligs ... - Woodhouse
Electric powered FF models - Horejsi
May in Muncie - Markos


Spring Cup Seguin Results
=========================

The weather Saturday morning was good except for the fact that the wind had
not decided on a direction. The middle of the field was very wet which
meant that we had to stay on the runways, which severely limited the useable
field in any direction. Once the wind finally took a ?set? the direction was not good.
After several delays, and three moves we called it a day after five rounds.
Everyone worked very hard to get their flights in and almost all of the
flights in rounds 4 and 5 went off the field. We ended the day with
three clean in Open Gas and two in F1C. F1C will be decided at a later date.

On Sunday we held the fly off in Open gas at 7AM and all the people were
off the field in three minutes. Round one of the Mini events started at
8 sharp with a stiff NE breeze. Six people had put in flights when
the torrential rains hit at about 8:30. We waited until about
11AM and a lull in the rain to get everyone packed up and off the field.
Fortunately no one got stuck, but the mini events were washed out and
have been rescheduled for the Tri-City 23rd Annual on 5 June, starting
at 0800. Thanks to everyone that attended (we had 24 contestants)
and we hope for better weather next year.

F1A (3 Flew)
1. Steve Spence 118 120 90 120 120 568
2. Mike Fedor 120 120 90 96 120 546
3. Mike Reeves 120 44 164

F1B (3 Flew)
1. Eddie Vanlandingham 120 120 90 120 120 570
2. Dick Wood 120 111 90 120 115 556
3. Jim Bradley 120 120 21 16 277

F1C (3 Flew)
1. Henry Spence 120 120 90 120 120 570
1. Reid Simpson 120 120 90 120 120 570
3. Faust Parker 120 120 90 47 377

Open Power (8 Flew)
1. Jackie Sheffer 120 120 90 120 120 192 762
2. Mark Troutman 120 120 90 120 120 127 697
3 Bob Hanford 120 120 90 120 120 0 570

P-30 (4 Flew)
1. John O?Dwyer 120 120 120 150 510
2. Bob Hanford Sr. 120 120 120 139 499
3. Jim Thornton 115 120 120 355

Faust Parker
Contest Director





NZ World Cup Events 2004 Plus other events
==========================================

Kotuku Cup - F1A
PlaceName Country Seconds
1 Lee Hines USA 2010
2 Antony Koerbin NZ 1967
3 John Harte NZ 1885
4 Phil Mitchell Aus 1854
5 Brian van Nest USA 1724
6 Steward Cox NZ 1443
7 Bill McGarvey NZ 1439
8 Chris Murphy NZ 1263
9 Henning Hyhegn Den 1258
10 Mikhail Kochkarev Rus 1239
11 Vin Morgan Aus 1221
12 Craig King NZ 1184
13 Rob Wallace NZ 1110
14 Linc Vincent NZ 930
15 Moira Vincent NZ 7

Kotuku Cup - F1B
PlaceName Country Seconds
1 Terry Bond Aus 1951
2 Ladya Horak Can 1947
3 Roger Morrell USA 1560
4 John Malkin NZ 1525
5 Linc Vincent NZ 1493
6 Alan McDonald NZ 1484
7 Karen Kenmir Aus 1259
8 Dave Ackery NZ 1273
9 Tim Harte NZ (Jr) 1245
10 Brian Van Nest USA 1240
11 Alister McKenzie NZ 1132
12 Leigh Morgan Aus 1061

Kotuku Cup - F1C
PlaceName Country Seconds
1 Henning Nyhegn Den 1290
2 Roy Summersby Aus 1274
3 Phil Smith NZ 1274
4 Rex Bain NZ 1030

Kotuku Cup - HLG
PlaceName Country Seconds
1 Tim Harte NZ (Jr) 355
2 Phil Smith NZ 297
3 Phil Mitchell Aus 289
4 Chris Murphy NZ 279
5 Lee Hines USA 278
6 Craig King NZ 232
7 Stu Cox NZ 197

Kotuku Cup - Open Combined
PlaceName Country Seconds
1 Rob Wallace NZ 540
2 Mikhail Kochkarev Rus 540
3 Chris Murphy NZ 180
4 Henning Nyghen Den 148

Kotuku Cup - Mini Combined
PlaceName Country Seconds
1 Vin Morgan Aus 740
2 Antony Koerbin NZ 719
3 Moira Vincent NZ 473
4 Phil Mitchell Aus 462
5 Roy Summersby Aus 360
6 Karen Kenmir Aus 246
7 Bernard Scott NZ 240
8 Terry Bond Aus 204
9 Mikhail Kochkarev Rus 2

Kotuku Cup - Catapult Glider
PlaceName Country Seconds
1 Lee Hines USA 237
2 Tamsin Smith NZ 172

Omarama Cup - F1A
PlaceName Country Seconds
1 Robert Wallace NZ 1871
2 Lee Hines USA 1770
3 Mikhail Kochkarev Rus 1692
4 Phil Mitchell Aus 1650
5 Antony Koerbin NZ 1275
6 Brian Van Nest USA 1270
7 John Harte NZ 1249
8 Stu Cox NZ 1221
9 Bill McGarvey NZ 1218
10 Craig King NZ 1162
11 Henning Nyhegn Den 1101
12 Moira Vincent NZ 743
13 Linc Vincent NZ 709

Omarama Cup - F1B
PlaceName Country Seconds
1 Alan MCDonald NZ 1268
2 Alister McKenzie NZ 1262
3 John Malkin NZ 1240
4 Tim Harte NZ (Jr) 1236
5 Terry Bond Aus 1228
6 Roger Morrell USA 1219
7 Leigh Morgan Aus 1197
8 Karen Kenmir Aus 1171
9 Ladya Horak Can 1168
10 Linc Vincent NZ 1114
11 Brian Van Nest USA 1105

Omarama Cup - F1C
PlaceName Country Seconds
1 Roy Summersby Aus 1260
2 Rex Bain NZ 1207
3 Phil Smith NZ 1185
3 Henning Nyhegn Den 1185

Omarama Cup - F1G
PlaceName Country Seconds
1 Terry Bond Aus 600
2 Roger Morrell USA 529
3 Linc Vincent NZ 411

Omarama Cup - F1H
PlaceName Country Seconds
1 Mikhail Kochkarev Rus 1680
2 Phil Mitchell Aus 1200
3 Stewart Cox NZ 654
4 Brian Van Nest USA 577
5 Moira Vincent NZ 30

Omarama Cup - F1J
PlaceName Country Seconds
1 Roy Summersby Aus 587

Omarama Cup - P-30 Rubber
PlaceName Country Seconds
1 Vin Morgan Aus 1101
2 Karen Kenmir Aus 706
3 Roy Summersby Aus 359
4 Terry Bond Aus 345
5 Lin Rodway NZ 285
6 Chris Murphy NZ 264
7 Stewart Cox NZ 120

Omarama Cup - Open Combined
PlaceName Country Seconds
1 Stewart Cox NZ 1121
2 Henning Nyhegn Den 997
3 Mikhail Kochkarev Rus 810
4 Craig King NZ 706
5 Antony Koerbin NZ 540
6 Roger Morrell USA 535
7 Lee Hines USA 527
8 Karen Kenmir Aus 521
9 Leigh Morgan Aus 515
10 John Malkin NZ 483
11 Rob Wallace NZ 446
12 Linc Vincent NZ 339
13 Ian Henry NZ 329
14 Moira Vincent NZ 257

Omarama Cup - Hand Launch Glider
PlaceName Country Seconds
1 Lee Hines USA 324
2 Chris Murphy NZ 279
3 Stewart Cox NZ 247
4 Phil Mitchell Aus 230

Omarama Cup - Catapult Glider
PlaceName Country Seconds
1 Lee Hines USA 373
2 Stewart Cox NZ 337
3 John Malkin NZ 208
4 Chris Murphy NZ 155
5 Owen Moore NZ 143

Omarama Cup - Kiwi Power
PlaceName Country Seconds
1 Lin Rodway NZ 535
2 Bernard Scott NZ 488
3 Alister McKenzie NZ 345
4 Chris Murphy NZ 82

Omarama Cup - Payload
PlaceName Country Seconds
1 Lin Rodway NZ 637
2 Chris Murphy NZ 540
3 Bernard Scott NZ 514




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

West Marine sells a tape that is about 2” wide that passes for Ikorex
with a glue backing. Even the weave pattern is the same as is
thickness (well, pretty close) . I think the sailboat folks use it
to wrap wire and cable rigging.

Cut a piece to size, peel off paper backing to expose glue, stick it on.
Hit with the hot iron to shrink if required and you are done.

I have only seen it in white tho.

Good luck,

Gene Ulm



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

Chuck,

I have had very good luck batching Icrex and Micafilm but treating it just like
it was a tissue patch. Cut out the damaged area and overlap the patch about
1/8" and apply the patch with clear dope. After the dope dries you can shrink
up any wrinkles without the patch pulling loose because the heat does not effect
the dope.

Jim Bradley



Seelig Glider Timer:
====================
Author : This email address is being protected from spambots. You need JavaScript enabled to view it.


Jim Farmer got his Seelig, but if anyone else is interested in a Seelig
glider timer, I have one in excellent condition setting in a drawer and availab
le.
Price is negotiable.
Bob Stalick



"Leeper"? simple answer...
==========================
Author : This email address is being protected from spambots. You need JavaScript enabled to view it.

Hi Kev,[and to all SEN readers!]

I got the #12 Arm Soar yesterday...another good job done by you.
So glad you liked our HLG/CLG article, and you are welcome.

To explain my "Leeper" nickname, of course it combines my name with
the fact my jumping ability is[ahem], shall we say, 'limited' these days.
This is due obviously in part, to the fact I am surprisingly not as
young as I was before[How could that happen?!], plus some leg injuries
I have incurred.
Tom Coussens gave me the 'Leeper' handle, sometime after I started calling
him 'Squatter'[from a picture...long story...].
The best news is that I just[yesterday,28Apr04]returned from a fantastic
trip 'Down under'[OZ & NZ specifically], where I had a magic time, both
with touring the countries and the competitions!
All this activity has healed and strengthened my legs, plus brought my
fitness back up to a more acceptable level.
I placed well in the 4 World Cup F1A events[a 1st, a pair of 2nds plus one
cockup]as well as winning HLG once and all 3 CLG comps.
Len Surtees[AKA 'Shirtsleeves']was pleased to beat me in the AFFS Champs
HLG comp, but my solace is that Craig King[NZ]used a BatCat 18[and better
air picking!]to pip us all!
Mind you, CLG for the lads down there is very much a new thing, in fact,
NZ have no rules set up yet. They were asking for my input, which I believe
they found useful.
At the Kotuku Cup, where I won F1A, HLG was taken by young Tim Harte, a few
days after his successful assault on the low-ceiling category F1N World
record.
I have him to thank, as they had to go home to Christchurch before the
Omarama
Cup event, thus allowing me a bit easier time of it to take HLG top place.

The entire trip was just such a 'Happening', as my good traveling chum,
Henning
Nyhegn so aptly stated, that my mere words are so inadequate a description.
The fantastic salmon dinners and the trip around Mt Cook snowfields were so
special that I must send a heartfelt general 'THANK YOU!' to all my friends
in OZ and NZ who helped make it so memorable.

Ciao,
Leeper

--- Lee Hines
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Power Book [ NFFS not Apple !]
==============================
Author : This email address is being protected from spambots. You need JavaScript enabled to view it.

Regarding Dennis Kargol's question about a successor to Keith Hoover's 1992
Power Book.
As the current proprietor of the NFFS Publications Services function, I am
unaware of anyone who might be doing such a project. If anyone is interested,
NFFS would be pleased to work with someone to produce such a book. Keith Hoover

actually began an update of the book, but was only started on the project
before he passed away.
FYI: the current 1992 Power book is still available from NFFS Publications
for $10 US, plus postage. There are about a dozen books remaining in stock.
Bob Stalick, NFFS Publications Services.




SAFETY ALERT: LI-POLY BATTERIES
===============================
Author : This email address is being protected from spambots. You need JavaScript enabled to view it.


Hi all,
FYI, info from the AMA website I thought you should be aware of.
Lee

[info follows below]

Emergency Safety Alert: Lithium Battery Fires
(Added 4/23/04)

Lithium batteries are becoming very popular for powering the control and
power systems in our models. This is true because of their very high energy
density (amp-hrs/wt. ratio) compared to Nickel Cadmium (Ni-Cds) or other
batteries. With high energy comes increased risk in their use.
The principal risk is fire which can result from improper charging, crash
damage, or shorting the batteries. All vendors of these batteries warn
their customers of this danger and recommend extreme caution in their use.

In spite of this many fires have occurred as a result of the use of Lithium
Polymer (Li-Poly) batteries, resulting in loss of models, automobiles, and
other property. Homes and garages and workshops have also burned.

A lithium battery fire is very hot (several thousand degrees) and is an
excellent initiator for ancillary (resulting) fires. Fire occurs due to
contact between lithium and oxygen in the air. It does not need any other
source of ignition or fuel to start, and burns almost explosively.

These batteries must be used in a manner that precludes ancillary fire. The
following is recommended:

Store and charge in a fireproof container, never in your model.
Charge in a protected area devoid of combustibles. Always stand watch over
the charging process. Never leave the charging process unattended.
In the event of damage from crashes, etc., carefully remove to a safe place
for at least a half hour to observe. Physically damaged cells could erupt
into flame. After sufficient time to ensure safety, damaged cells should be
discarded in accordance with the instructions which came with the
batteries. Never attempt to charge a cell with physical damage regardless
of how slight.
Always use chargers designed for the specific purpose, preferably having a
fixed setting for your particular pack. Many fires occur in using
selectable/adjustable chargers improperly set. Never attempt to charge
lithium cells with a charger that is not specifically designed for charging
lithium cells. Never use chargers designed for Ni-Cd batteries.
Use charging systems that monitor and control the charge state of each cell
in the pack. Unbalanced cells can lead to disaster if it permits overcharge
of a single cell in the pack. If the batteries show any sign of swelling,
discontinue charging and remove them to a safe place—outside—as they could
erupt into flames.
Most important: NEVER PLUG IN A BATTERY AND LEAVE IT TO CHARGE UNATTENDED
OVERNIGHT. Serious fires have resulted from this practice.
Do not attempt to make your own battery packs from individual cells.
These batteries cannot be handled and charged casually such as has been the
practice for years with other types of batteries. The consequence of this
practice can be very serious and result in major property damage and/ or
personal harm.

AMA Safety Committee




--- Lee Hines
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FAI Qualifier...
===============
Author : This email address is being protected from spambots. You need JavaScript enabled to view it.

Just a reminder that on Friday, May 14, 2004, the Detroit Balsa Bugs will be
holding an FAI qualifier to accumulate towards the Finals. This will be held
the day before our Inter-City Meet in Muncie, Indiana at the AMA field.
There is no entry fee and there will be no rounds. Flight time will be
determined by weather with an understanding this is only to accumulate time.
Max-outs will be rewarded with beer at the Shailor motorhome.
So come early to the meet, test and get free time!
Hope to see you all there.
Bill

A Few Seeligs ...
=================
Author : This email address is being protected from spambots. You need JavaScript enabled to view it.

I have a few Seelig timers left. See my list for details of what I have.

Michael J Woodhouse, Norwich, UK.
Free Flight Supplies has secure internet credit card facilities.
All mail to: -
web site: -

on 29/4/04 5:59, SCAT user at This email address is being protected from spambots. You need JavaScript enabled to view it. wrote:


Electric powered FF models
==========================
Ivan Horesji

State of art of electric power units 04/2004

I like very much the idea of F1Q, but I am afraid that some of the
proposals woule open big can of worms. The limitation of the power is not
simple!!!
We can learn from the experience of RC modellers but our requirements are
partially different. Typically, we need maximum power provided within
rather short time period.

The power unit is a chain of more parts.

Motors
------
1. Ferrit magnets, carbon brushes. Very cheap, mass produced motors. Lower
efficiency. For the large power output a motor made for low voltage can be
used and heavily voltage overloaded. Such a motor can provide large output
but it can burn out after few minutes of run. If the motor type is not
limited it is probably the way to go but in wrong direction.
2. Motors with good quality magnets (neodym or similar). Better efficiency,
more expensive. Can be overloaded, too.
3. Brushless three phase motors. The best efficiency, made in low quantity.
Expensive but affordable.

Speed controllers – excellent solution for us.
It is the electric control unit installed between battery and motor.
Another cable from the controller connects the unit with the receiver which
controls the revs AND in usually supplies the onboard electronics. In case
of brushless motors, the controller generates also the 3-phase current from
the battery DC. These controllers are much more expensive than those for
the DC motors. Still affordable.

I believe that the speed controller is invoidable device for our purpose
from more reasons:
- it can provide very simply the On/Off function. In the common RC
equipment, the controller is connnected to one of the receiver servo
output.
- most of the controllers can brake the motor shaft (prop). Inavoidable
function for our purpose. If not used, even the folding prop will not fold
but will rather freewhel forever, even if the motor is not supplied from
battery!!!

The receiver signal can be replaced by a servo tester (a small and very
cheap servo controller with just On/Off would be better for the purpose),
controlled maybe mechanically by an arm (connected to a mechanical timer).
The servo controller can be supplied from the speed controller withou any
additional wiring (BEC function of the speed controller).
All the wiring is very simple.

Gearboxes
---------
Very common in electric power units and cheap, no reason to be worry of
them.

Battery
-------
1. NiCd: SAFE, cheap, long lifetime, low inner resistance, lower capacity.
2. NiMh: similar, but shorter lifetime, higher capacity, slower charging.
3. Li xx: STILL VERY DANGEROUS FOR US !!!, expensive, very high capacity.
Currently under rapid development, the maximum available current is
increasing every few months. Overloading, overcharging or just puncture
(crash, DT) will cause VIOLENT FIRE!!! The case is made of fine plastic
sheet.


Charging
--------
From the safety reasons, I would limit the debate to the Nixx. Due the long
time necessary to charge the NiMh I would further limit to NiCd only.

- Any battery can provide the maximum voltage (and thus the power output)
in the first stage of discharge.
- If you want to get most from the battery, it should be fully discharged
before new charge. The battery should be cool before charging.
These facts would make necessary “one charging cycle – one flight”
necessary, at least for the contest flying. Flying in FF style (lot of
starts within short time) will ask for more battery packs.

Chargers
--------
Chargers for up to 7 NiCads are usually cheaper. They can be fed directly
from the 12 V car battery, without any voltage mutiplcation.
Chargers providing larger currents (5 Amps+) are more expensive. The
charger must be fed on the field from car battery, the car must be close to
the start position. Moving external (heavy) car battery is not quite simple
task.
The typical dicharge/charge cycle can take some 30 minutes.

Fuse
----
It is something extraordinary in the electric power units. I asked some
people and was told that the accuracy of any fuse isnot acceptable, the
switch off current can be in range +/- 30%!!! Also, the enviromental
temperature of the fuse is important. Certainly we should avoid spray
“supercooled” fuse cases.


RC approach
-----------
There is a class of electric powered gliders, called LMR (Limited Motor
Run) or very unofficially F5J, as it is still not even a provisional FAI
class. There are 3 versions of the rules, which differ in the “size” of
model. One of them would be close to our requirements:
The power unit is limited to motor 400, supplied from max. 8 NiCd cells.

Resume
------
All in all, I would take lesson from the LMR class. So, I would personally
prefer the French idea, but without the fuse. Maybe the wing area could be
ommited, maybe the minimum weight should be prescribed to avoid building
“lighter than air” airframes.

New comments
------------
After I read the article from Taapio, I contacted Mr. Tomas Bartovsky. He
solved similar problem, regarding limitation of the F3B winches output.
They use now the resistor, but the problem is not still fully solved. He
would not recommend the resistor for us. Instead, he suggested a special
speed controller which would cut-off the excessive current.
Then I contacted the producers of the speed controllers JETI, one of the
best selling mark in the world. I was told that the suggested solution
would be theoretically possible, but: “ forget it, prescribe just simply
the type of cells, number of cells and their weight”.







May in Muncie
=============
Author : This email address is being protected from spambots. You need JavaScript enabled to view it.



Roger,
The Free Flight and FAI calendar for the International Aeromodeling Center in
Muncie, IN for the month of May is worth considering for those who don't mind
a little travel and who also are interested in picking up some America's Cup
and National Cup points.

To start with, the Detroit Balsa Bugs will be hosting their annual
Inter-Cities contest on May 15 -16 for FAI competition plus a good number of Na
tional
Cup events. They have also scheuduled Friday, May 14 as a separately sanctione
d
contest for FAI team selection to accomodate those who need to accumulate
some more flight time to qualify for the Finals.

The following weekend is really full. The Hoosier Cup FAI will be on May 22
- 23 sponsored by the Chicago Aeronuts. In addition, the COFFA will sponsor
a "one-design" contest on
Friday, May 21 (model designs selected by the NFFS for the previous 5 or 6
Nats). Also on Sat and Sun the CIA will sponsor its annual Oldtimer and
Nostalgia contest.....wait, there's a lot more: The FAC will hold a scale con
test
on the weekend and the CIA will continue into Mon and Tue (May 24-25) with the

"National Cup Challange."

Most of the contest information can be found on the NFFS website in the
competition calendar.

The field at Muncie is about one mile wide EW and 1.5 miles long NS.
However, to the east is farmland for about another 3/4 mile. The crops will be
just
sprouting at this time of year. If your model lands on private property, it
is imperative that the owner's permission be granted before retrieving it. Of

course, we all know better than to take our chase bikes and ATVs into those
fields.

Chuck Markos



...................................
Roger Morrell