Letters to the Editor - 2004/05

Correction
The wingspan of the Electric Flash RC
park flyer featured in the March issue was
incorrectly cited as 28 inches; the correct
measurement is 44 inches.
We apologize for any inconvenience
this may have caused.
—MA staff
Sleeve Valve Engines
For as much as I respect the knowledge
demonstrated by [MA’s “The Engine
Shop” author] Joe Wagner, I fear that I
have to differ with him regarding his
remark [on page 9 of the March issue] that,
“… rotary sleeve valve engines powered
thousands of British combat airplanes in
WW II.”
Thanks to the generosity of H.M., at
differing times I was able to blunder
around the skies between a number of
those sleeve valve engines, and I can state,
without fear of contradiction, that the
Bristol Hercules radial engines—and the
later Centaurus—were not rotary valve
equipped and therefore bore no
relationship to the RCV engines, as
implied in Mr. Wagner’s note on page 9 of
the March issue.
The Hercules pistons traveled up and
down inside a liner—or sleeve—which,
itself, reciprocated (up and down) a very
limited amount, in addition to oscillating
left and right through an arc of about 30°
only.
The skirt of each liner engaged a very
small crank that was driven off the
engine’s propeller speed reduction gears.
That crank had a throw (at a guess) of
about 21⁄2 to 3 inches. This limited
reciprocating motion, coupled with the
limited oscillation, enabled the inlet and
exhaust ports, that pierced the sleeve, to
align with ports cut through the aluminum
alloy, finned cylinder barrels.
Incidentally, although I have seen a
couple of involuntarily disemboweled
Hercules engines during my service, it is
only now that I discover, through reading
the description of the sleeve drive, that
there were 56 gears involved in driving the
propeller speed reduction and the 14 shafts
driving the sleeves!
Jim Newman
Kent City, Michigan
USA-1
I greatly enjoyed the USA-1 article by
Bill Werwage that appeared in the March
2004 issue. Not only is the airplane very
nice-looking, but the history made
interesting reading.
I would love to see more on CL Stunt.
Please keep up the good work.
David Zwolak
Philadelphia, Pennsylvania
Misrepresentation
on AMA Applications
On the application for AMA
membership we’re asked to check the
boxes for the type of modeling that
interests us. When I filled mine out the last
time, I didn’t see a box for Scale
Aerobatics or for IMAC, the Scale
Aerobatics competition SIG. So I naively
figured I’d check “Scale” and also check
“precision aerobatics.” I figured, “Hey,
those things fit the criteria close enough
and they’ll understand what I mean.” But I
had no idea that checking those boxes
would be taken so literally and that I was
actually adding numbers to a group that I
really don’t have an interest in nor do I
participate in.
I wonder how many of us who have an
interest in SA checked the box for “Scale”
or for “precision.” In fact, AMA really has
no way of knowing how many people have
an interest in Scale Aerobatics. They just
see that there are a large number of people
interested in Scale modeling. Do you think
that the Executive Council counts SA
enthusiasts as involved in Scale activities?
I don’t really know, but I kind of doubt it.
And it’s clear that our numbers as counted
in IMAC memberships don’t really tell the
whole story.
How many SA enthusiasts ever actually
compete? Probably a very small fraction. I
know that each time I go to the flying
field, almost half the airplanes there on
any given day are SA aircraft flown by
Sunday fliers and sport fliers. Of course,
none of them are members of IMAC. So
how are we counted? Does it matter? I
think it does matter because decisions are
being made on an ongoing basis that affect
many aspects of our hobby, and a good
number of those decisions are based in part
on the numbers of participants. In fact, I
think decisions about the future direction
of the AMA magazine are highly
dependent on those numbers.
I’d like it to be understood that Scale
Aerobatics is far bigger and more diverse
than our IMAC SIG numbers would
indicate and that we need to be counted. It
just doesn’t seem like those of us with SA
interests have a realistic representation.
Mike Hurley
Westminster, Colorado
Thanks to Many
One goes through life knowing he is
making friends and perhaps followers but
has no reason to acquaint that with “how
many.” That is until he has a problem
such as my time in the Moffitt Cancer
Center in Tampa, Florida.
Moffitt is a fine operation. They know
what they are doing but their aggressive
cure methods leave a lot to be desired!
After five hours of oral surgery,
prognosis is fine and I am finally back
home for two months of recovery.
The main objective of this letter is to
have a way to thank the great number of
people who have given me attention. I
have a stack of “get well” cards, every
one of which was appreciated and
cherished. My E-mail has been swamped
with kind messages which also have fine
meaning to me. As you might imagine,
all this came as a surprise and in reality
demonstrates what fine people modelers
are!
Please accept this letter as my way of
letting you know of my appreciation.
Also that one of my cherished
possessions is the friendship of so many.
God has been so good to me and I thank
him every day!
Hal deBolt
Sun City Center, Florida
Mahalo!
I am a member of the LIARS club in
Suffolk County, Long Island, and I took
an extended vacation in Maui, Hawaii,
during November, December, and
January. I found the Maui RC Pilots club,
and I am writing to tell your readers how
great the members treated me.
I would like to especially thank
members Ian, Steve, and Jed. They
showed me helpfulness, skill, and
camaraderie, and they made me, a New
Yorker, feel welcome and at home.
Mahalo (thanks) to my Hawaiian flying
buddies.
Bob Berger
Stony Brook, New York
Feedback From a New Member
I very recently got into RC electric
flying through a community open house
at the local club. I was online joining the
AMA when I noticed the magazine and a
series of articles by Bob Aberle. They
looked good, so I printed them out and
read them, and boy, did I learn a lot!
I wanted to thank you all for making
those available and compliment you on
the clearness and thoroughness of the
material. MA
Lenny Lipton
Bethel, Connecticut
Model Aviation, 5161 E. Memorial Dr., Muncie IN 47302
Letters to the Editor
May 2004 9