SEN 981 - 4 Nov 2005

SCAT Electronic News 4 Nov 2005 issue 981

Table of Contents
Southwest FAI Challenge RESCHEDULED !! - -Booth
F1A electronic bunt questions - Murray
Vasi will not come to MaxMen-2006
2006 Finals - McKeever
Charlie's sister

Southwest FAI Challenge RESCHEDULED !!
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Hi Roger,

I received a surprising amount of feedback that asked us to re-schedule the
SW FAI Challenge. So we did it !

We received notice from the City of Boulder yesterday that our lakebed use
permit had been approved for the new dates November 19 & 20. The sanction
has been transferred and we are back on. Jon Zeisloft, our primary local
contact in Las Vegas has promised perfect weather and a dry lakebed. OK,
not really, but he did say in the past they have had many nice weekends into
December, but it is the fall and the weather is unpredictable. The national
weather Service web page does not project that far ahead, but Accuweather
has Friday November 18 listed as 72 degrees and wind at 3 mph. More
importantly, there is no rain projected on their forecast for the next 2

I will post more information this weekend, but I wanted to get this out as
soon as possible.

Thanks to everyone who sent us a note or called.

Bill Booth

F1A electronic bunt questions
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Hi Roger,

I hope this is the right way to post questions on your fantastic

I am setting up my first electronic bunter and wonder whether any of the
F1A experts would be kind enough to offer their advice on the
bewildering array of possibilities an e-timer opens up. (The model has
two servos, one controlling the stab and one controlling the wash-in to
the inside wing.)

1.. Is it worth taking out inner wing wash-in during straight tow? I
am used to towing with a small amount of opposite rudder to neutralize
the wing wash-in which gives the model a degree of "steering" by varying
line tension (tow speed). I hope taking out wash-in would eliminate any
weaving tendencies but am worried that the model will be less
"steerable" without a balance of opposing forces, as well as the
constant moving of the wing servo during long tows adding to the drain
on the batteries.
2.. Is it better to launch straight or to try to bank & turn during
the bunt? My inclination is to launch straight without any turn during
the bunt sequence, eliminating zoom rudder deflection and taking out
wing wash-in (so there will be no transition from dragging to lifting on
the washed in wing) during the acceleration ( hook straight, latch open
phase). I am hoping this will reduce the need to keep one eye on the
model whilst the desperate sprint phase is on at the bottom end of the
line (and streamline the model for a bit more speed as well?) Can't
imagine having to hang on till the model turns in the right direction
whilst covering ground like a greyhound would be a reliable way to go.
3.. Should one keep the circle tow stab incidence during the pre
launch acceleration phase for extra line tension or should one lower the
stab for extra speed? I plan on circle towing with extra wash-in on the
inside wing and extra stab incidence to compensate for the effect of the
towline drag and give a tight circle with a realistic sink rate for
assessing the air the model is in. Should I keep the extra stab
incidence during acceleration to help get good line tension and rely on
this to pitch the model up at release or should I take it out to get
extra speed and have a quick blip of up to pitch the model upwards on
release? (I presume personal timing sequences are top secret but if
anyone is prepared to give me some suggestions they would be very
gratefully received.)
4.. What changes if the day is windy? Accelerating the model will be
easier but the velocity will be air speed not ground speed so the
momentum will be less. I would expect this to affect the bunt and would
assume that perhaps a different setup will be required with shorter
times for the cruise and bunt sections after release, maybe even having
to bank and turn to lessen disturbance from gusts. Is this correct and
do most have a windy launch program and, if so what changes?
5.. Final question - towlines. Is there still a huge variation of
opinion on which is best or has a preferred type risen to the surface. I
would like to use Russian rod but am worried that it is too thick at 1mm
- the drag on the model when circling will knock enough out of the glide
with the line attached to make picking air difficult when lift is very
marginal (for me anyway). With an e-hook, a snapped line is not a lost
model anymore so provided it does not happen twice in one round the
consequences are not serious. I am tempted to try 50 kg Kevlar with a
leader of 15m Russian rod but am scared I will have no fingers left
after a while (less serious now that it is not necessary to build models
anymore but still required to earn the greater income needed to buy

As a final aside, would anyone like to comment on thermal hunting trim?
I take conventional trim to be about 2mm wash-in on the inside wing and
trimmed near the stall to tighten up in lift. I am confused by reports
of Wakefield fliers flying with the outside wing washed in (or inside
washed out) and (as I understand it) the fin lifting away from the turn
to resist spiraling in if lift is strong. I don't really understand how
this would prevent a spiral dive once the model speeded up, say in a
dive after a stall. In a normal glide the outside wing would be dragging
against the rudder turn - but if it speeded up the outside wing would
start lifting adding to the rudder turn - with no way to recover from
there as far as I can see? Do any glider flyers use this trim, is it
really superior and how does it work in reality?

Many thanks for your efforts in keeping this wonderful forum going.


Neil Murray

Vasi will not come to MaxMen-2006
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My dear customers and friends,
It seems like I will not be able to make my next trip to
California next February. There is family reason- we do
expect another baby (girl) right at the middle of feb.
That's why I am asking you to keep my not coming in
mind and make your orders earlier to give me and my
teamwork couple of month of time to get stuff done.
I do plan to mail some large boxes to USA at the
beginning of January to Don Zink and Ed Caroll so, they
will help to pass orders directly to you.
So, see some of you in Ukraine next summer and probably
nex endless October!
Best thermals!
Your pal,
Vasily Beschasny

2006 Finals
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I have submitted a proposal to be Contest Director at the 2006 Finals. The
proposal has been accepted by the Finals Committee and the 2006 Finals will
be at Lost Hills, Ca beginning October 9, 2006 with model processing. October

10 flying starts with F1B and C (F1A times), followed on October 11 with F1A
and B (F1C times), and concluding October 12 with F1C and A (F1B times).
Friday the 13th can be used as a reserve day and potential flyoffs. Sorry abo
that Friday the 13th deal, should bring the winners luck in Ukraine.

My Contest Administrator is Bob Norton. I have had many volunteers to help
run the contest but it is my desire to make this Finals as fair and as
smoothly run as possible so I would like to add interested parties to the Final
Team. I need volunteers for the jury, score keeping help and model processors

for both spot field processing and winner processing.

My current team has come up with several ideas that should make this Finals
one of the best and I look forward to selecting a great team to represent the

United States in 2007. Please send me an E-mail and let me know your
interest. As a bonus, next year's Finals is between two premiere events, The
Invitational run by Juan Livotto and the Sierra Cup World Cup. Both events
should draw international competitors which may assist us on timing issues. I
you are an interested flyer outside the United States, please let me know if
you are willing to time. As with the last Finals, compensation will be paid
for timers willing to time for the three event days.

I know we will be selecting the best team possible to represent us in
Ukraine. I look forward to hearing from volunteers that would like to assist
us in picking our team.

Thanks, Mike McKeever

Charlie's sister
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FOR YOUR INFORMATION: Charlie Sotich, stalwart of model aviation and free
flight and Secretary of the IMACS lost his sister in her passing thursday 27
October 2005. Sympathy cards can be sent to him at 3851 W. 62nd PL,
Chicago, IL. 60629-4622. We shall miss you at our annual banquet Pat.

Roger Morrell