Free Flight Scale - 2008/03

140 MODEL AVIATION
HI, GANG! You will receive this issue at roughly the height of the
building season. This year is the 30th anniversary of Flying Aces Club
(FAC) Nats competition, and it may see multiengine subjects in
abundance.
FAC Hall of Famer Vance Gilbert is making progress on his
scratch-built version of the Short S.26: a beefy, British, four-engine
flying boat. There is no lake at the Geneseo, New York, flying field,
but this model is sure to make a big splash with the crowd.
Andrew Ricci is well along on his 30-inch-span Arado Ar.440. It
bears a similarity to the Heinkel He 119, but it may have an even better
layout for a high-performance FF Scale subject. I am still chipping
away at my 1/2-inch-scale (62.5 inch span) Lockheed Constellation
Model L-049, which will sport TWA livery.
Those are just a few of the many multis that are being built for the
2008 flying season. There is only one way to see them up close, and
that is to attend the FAC Nats at Geneseo. Scale judging will take place
Thursday July 17, 2008, and flying competition is July 18-20. See the
last paragraph of this column for event contact and registration
information.
Building activity is by no means limited to
multis. Numerous other fine models are being
made ready for FAC events. Tom Hallman, a
superb craftsman, is nearing completion of his
handsome Junkers J 1, which is being covered
with camouflage tissue that is neatly printed in
full color using a computer printer.
The Junkers’ corrugated metal areas are
The 30th anniversary of FAC national competitions is coming!
[[email protected]]
Free Flight Scale Dennis Norman
Also included in this column:
• Gordon Roberts’ fabulous
propeller
• Bhagat Dhillon’s SFA legacy
• Share the joy of FF
• Bill Warner’s guide for
beginning FF modelers
The formidable fuselage of Vance Gilbert’s Jumbo S.26, which
will make its debut at the 2008 FAC Nats. Gilbert photo.
Midconstruction photo of Andrew Ricci’s 30-inch-span Arado Ar.440, which promises
to be a contender in this year’s FAC contests. Ricci photo.
Three views of Tom Hallman’s Junkers J 1 fuselage. He hopes to
finish this project in time for the 2008 FAC Nats. Hallman photo.
Tom Hallman’s J 1’s partially covered flying surfaces. Lines
effectively represent corrugated covering. Hallman photo.
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Half view of Gordon Roberts’ design for making a block for carving a propeller of true
helical pitch. This may be the final answer to an old debate. Roberts diagram.
The author’s Air Ace Models Walnut Spitfire Mk XIV makes excellent use of a 6-inch
Roberts propeller with true helical pitch. Patrick Norman photo.
Japanese tissue printed with color copier to cover the Sky Bunny. You can order
customized sheets for $15, postage included, from Air Ace Models. Patrick Norman photo.
convincingly portrayed using fine lines. Tom
has even made meticulous wheels with the
manufacturer’s name on the wheel covers.
Such attention to detail gets the crowd’s juices
flowing even before the model takes to the air.
Gordon Roberts, the FAC’s legendary Ace
of Aces (with 534 Kanones in FAC
competition) has gifted us with two excellent
articles detailing his efforts to design a
propeller with constant helical pitch. He
recently presented me with a 6-inch propeller
designed to his specifications. I finished it and
put it on my new Walnut Scale Supermarine
Spitfire Mk XIV, with phenomenal results.
Gordon’s idea was to create a propeller
that produces thrust for every bit of its length,
and I believe he has done it. On its maiden
attempts the Spitfire soared gracefully and
gave long, stable flights of nearly a minute.
With tweaking I feel certain that maxes are
possible, and I have the tingling sensation that
the Spitfire will probably go out of sight one
calm, thermal-filled day.
Although Gordon presents his ideas at
length in issues 102 and 108 of the
Crosswinds newsletter, I will summarize the
information for your ready reference. If you
would like copies of issues 102 and 108,
contact Russ Brown. If you want a copy of
Gordon’s articles only, send me $5 and I will
mail them to you, postage included.
Gordon concedes that propeller carving
may have become a lost art because of plastic
propellers, but they do not have true helical
pitch. Therefore, although they are satisfactory
for most uses, they do not give the ultimate
thrust that is possible.
Most of us are content with propellers that
give satisfactory flights. In serious
competition (and Gordon wrote the book on
that subject), even a modest improvement in
propeller thrust can spell the difference
between a Kanone and an also-ran.
Gordon begins his discussion by pointing
out that as far back as the May 1951 issue of
the English magazine Model Aircraft, J.H.
Maxwell drew attention to the fact that socalled
“traditional block” propellers (those
with a straight taper in depth from the halfway
point to the tip) do not give constant pitch.
The “X” block design begins, at the hub,
with constant helical pitch, but it becomes less
effective and wasteful of wood as it
progresses to the tip. J.H.’s solution was to put
a “concave dip” in the side elevation from the
halfway point to the tip.
His ideas were largely ignored for nearly
50 years, until John Barker rediscovered them.
In the November 1997 Sam 35 Speaks, John
confirmed J.H.’s ideas about the outer half of
the blade.
Jim Fullerton of Australia also confirmed
J.H.’s ideas. Gordon notes that the Aussies
were a formidable force in post-World War II
Wakefield competitions, and their propeller
designs were certainly doing their job.
Gordon’s contribution to the story is to
allow the inner portion with the now-almost
universal cutout to half the depth at the hub to
be laid out with a constant pitch. A Ph.D.
scientist, he gives a detailed discussion of the
mathematical calculations needed to arrive at
true helical pitch.
Gordon has done calculations for several
03sig5.QXD 1/24/08 3:15 PM Page 141sizes of propellers, to cover most options for
FAC events, including 12, 10, 8, and 6 inches
in diameter. A sample for a 6-inch-diameter
propeller block for true helical pitch
accompanies his article. Patterns for the other
sizes I listed, with the mathematical reasoning
for them, can be found in the reprints I
mentioned.
Gordon tested his theory by carving
several propellers. He found a significant
improvement in propeller performance. He
concluded his comments by giving tips for the
order and method of carving blocks for
making propellers of true helical pitch.
First, drill the hole for the propeller shaft in
the block using a drill press to make sure it is
vertical. Second, cut the outer tips using a
band saw. Third, cut the center cutout (side
view). Fourth, cut out the two dips on the face
elevation.
Carving technique is beyond the scope of
this effort, but there is an excellent discussion
of the process in an article by Steve Griebling,
a meticulous craftsman, in issue 100 of
Crosswinds.
I am saddened by the loss of any modeler,
but this passing should be noted out of
comradeship and respect for the shared
interest in our wonderful hobby. Bhagat
Dhillon created and administrated the hugely
successful Small Flying Arts (SFA) Web site.
It was a home for FF Scale modelers around
the world.
Thousands who shared a passion for model
aviation found an SFA forum, which let them
exchange ideas freely and enthusiastically.
Bhagat managed SFA and sustained it at his
expense with his considerable energy.
He was suddenly taken from us by a
massive heart attack at age 47. Since he
appeared to be in great health, this has come
as an incredible shock to his family and
friends.
Dhillon’s sons, Arjun and Derek, are doing
their best to continue SFA, but they are young
and in school. They are looking for others to
help and eventually take over the Web site.
The tentative plan is to either sell the Web site
or pay someone who will dedicate the same
amount of time and care that Bhagat did in
managing it.
Anyone who is interested in further
details should contact Arjun Dhillon. The
best tribute to Bhagat would be to continue
the fine work that he was doing with SFA.
As I have previously written, since we all
have expiration dates, it is vital that each of us
makes an effort to share model aviation with
the young. Through the years I have made an
effort to share it not only with my eight
children, but also with my grandchildren
(which currently number nine). I have taught
about model airplanes to countless groups of
school students, and I have had the pleasure of
mentoring many in my workshop.
I am currently taking my grandchildren to
Cleveland Free Flight Society contests to give
them an opportunity to experience the joy of
FF. Since five of my grandchildren live out of
state, I must content myself with taking the
four “locals” (ranging in ages from 4 to 7) to
the CFFS contests.
Because they are young, their parents
usually come. Time on the field is limited to
two hours. More than that might be
burdensome for them.
At this point all are enjoying the contest
experience, and I have made sure that each
has at least two or three models apiece to fly. I
am not referring to junk balsa gliders found at
discount stores. They do not generally
perform well, and nothing can turn off a
potential modeler more than attempting to fly
models that are essentially incapable of
satisfactory flights.
Last year I began handing fully wound,
high-performance FF Scale models to even
my 3-year-old grandchildren. After a few
fumbling attempts, they were able to release
the airplanes and watched in awe as they
soared away for flights of nearly a minute.
Nothing I could have said or done would have
given them more joy.
For the 2008 flying season I have built
four Sky Bunnys, designed by Bill Warner,
for my pint-sized flying buddies. The design is
excellent for teaching a new flier the FF
basics.
The Sky Bunny has adjustable tabs on the
wing, stabilizer, and rudder to show the effects
on the model’s performance. The “stick”
fuselage permits easy adjustment of the wing
and allows one to demonstrate the impact of
wing position on the aircraft’s flight.
The kids have been dubbed “Flying
Tigers.” Special markings have been created
for their models, which sport sharks’ teeth, an
early US insignia, wings covered in black on
the underside (to make them easier to spot at
altitude), and garish, flamelike yellow-andblack
tiger stripes on the top sides.
To keep things from becoming too
uniform, I covered each model’s tail surfaces
in the pilot’s favorite colors (e.g., my
granddaughter, May, likes pink and white). I
also printed, in large letters, each child’s name
on the underside of the wing.
Bill Warner wrote a 14-part series of articles
for Model Builder magazine between
November 1987 and December 1988. The
features were beautifully illustrated by Jim
Kaman and were intended as a guide for
beginning FF modelers.
When I realized that this information was
no longer readily available, I contacted Bill.
He graciously gave me permission to reprint
them. I brought all 14 articles together in an
82-page booklet entitled Hey Kid! Ya Wanna
Build a Model Airplane?
These books are currently available from
Air Ace Models for $20 each plus $3 for
shipping and handling. Those who are
interested can order by contacting me.
As I mentioned at the outset, the FAC will
celebrate the 30th anniversary of its Nats this
summer. If you have not already done so, I
strongly recommend that you contact Colonel
Lin Reichel, Commander-in-Chief, at FAC
GHQ for registration and housing
information. The 2008 edition will probably
be another record for this event. Until then,
build well, build often, and enjoy much! MA
Sources:
Air Ace Models
(216) 631-7774
[email protected]
Arjun Dhillon
(920) 385-8367
[email protected]
Colonel Lin Reichel, Commander-in-Chief
FAC GHQ
3301 Cindy Ln.
Erie PA 16506
Russ Brown
4909 N. Sedgewick
Lyndhurst OH 44124
142 MODEL AVIATION
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