CL Navy Carrier - 2012/10

The CL Navy Carrier event has been flown at the
National Aeromodeling Championships for 63 years. The
first time it appeared was at the 1950 Nats at the Dallas
Naval Air Station. For many years, the U.S. Navy sponsored the
Nats as part of its recruiting efforts, and the practice continued
for approximately 25 years, producing fond memories of Navy
hospitality for many of our “seasoned” modelers!
For the first six years of CL Navy Carrier flying, the contest
was a Navy event. The Navy supplied the carrier deck, dubbed
USS Smallfry, and specified the rules. Many of the rules we
currently use are derived directly from those Navy rules.
The sizes of the carrier deck and models have remained
fixed throughout our history until Profile models were allowed
to expand to a 50-inch span to include some of the existing
Profile kits.
The original 44-inch span size limit was intended to
produce a carrier deck and model of approximately the same
proportions as the operational straight-deck aircraft carriers
of the day. Original specifications also called for a maximum
58-inch length and 17-inch height. Those specifications were
set so that the models would fit on a 1/12-scale standard aircraft
carrier elevator and fit into a 1/12-scale hangar deck.
The Scale Model Bonus has always been 100 points.
Requirements for Scale models have been refined throughout
the years from rather general requirements originally, to the
specific tolerances and requirements of today. Since it was a
U.S. Navy event, only U.S. Navy aircraft models could earn
the Scale Model Bonus in the original rules. By 1955, the rules
even specified which aircraft could be modeled.
There were 33 aircraft listed, of which eight were biplanes
and five were jets, limiting the number of practical aircraft
for modeling to roughly 20. When the AMA took over the
CL Navy Carrier rules, the U.S. Navy restriction was initially
retained. The number of eligible aircraft was expanded
considerably in 1969 with the inclusion of naval carrier aircraft
from all countries.
The winner of the first CL Navy Carrier event was Cal
Smith. His Douglas AD-2 Skyraider was built to the 44-inch
wingspan limit of the rules. Its wing area was roughly 305
square inches.
Cal’s model was closer in size to the models currently being
flown rather than to the smaller models that evolved in the
early years of the event. Cal used an O&R .60 ignition engine.
His only speed control was a second set of ignition points,
which allowed for a single, preset low-speed power setting.
Originally, there was one class of large CL Navy Carrier
models and a small 1/2A class, flown on 35-foot lines. By 1955,
the 1/2A event had been dropped. There was originally no
engine size limit specified in the AMA
rules, although the current .65 cu. in. limit
was soon adopted.
In 1967, Class I models with a displacement limit of .40 cu.
in. came into being, and in 1969 the Profile Navy Carrier event
first appeared in the AMA rulebook.
Although it was an official AMA event, Profile Carrier was
considered a category for beginners, and there was a restriction
at the Nats against entering Profile Carrier if one was flying
either of the Scale Carrier classes.
The Profile rules went through a series of engine restrictions
that were focused on limiting competition. Those ineffective
restrictions generated far more controversy and arguments
than new modelers.
The original scoring system was retained until 1976, when
the scoring was changed to deemphasize
high speed. For good or for ill, that was
also the fi rst year that a Profi le model
was hung on its propeller for slow speed
at the Nats. The original scoring system
has been retained in the unoffi cial
Nostalgia Navy Carrier events of the
Navy Carrier Society (NCS).
Rules Proposals
I am writing this column in July and
the next major changes to the Carrier
rules are currently being discussed. In
addition to the possibility of adding
Electric Carrier (E-Carrier) events to
the AMA rulebook, one of the biggest
potential changes may be the inclusion
of RC technology for controlling
auxiliary functions on Navy Carrier
models.
To fi nd out the results of the voting
on various rules proposals, check the
Competitions section of the AMA
website. By the time this column is
published, the results will be available.
The 2.4 GHz spread spectrum RC
technology is being tested in some areas
to gather data for the decision on adding
such technology to Navy Carrier fl ying.
There is a photo this month of Tony
Naccarato’s Profi le Carrier MO-1, which
uses radio control to operate the throttle.
The fi rst time I saw Tony fl y a Carrier
model with a radio-controlled throttle
was approximately four years ago in
Phoenix.
Fairey Firefl y
A new model making the Carrier
competition scene this year is pictured in
this column. Wayne Buran has produced
a Fairey Firefl y in the T-2 trainer variant.
The Firefl y served the British Royal
Navy during World War II and beyond
as a fi ghter and reconnaissance aircraft.
I’m fond of the Firefl y and built one for
Class I in the early 1970s.
Wayne’s Firefl y has a 41-inch
wingspan and a 33-inch fuselage. Power
is from an Irvine .36 fi tted with an O.S.
4BK carburetor and turning an APC 9 x
6 propeller. The model is equipped with
a Brodak three-line control system.
U/Tronics Systems
Electronic throttle controls were part
of my last column, but I failed to give
details of the system. Clancy Arnold
makes the U/Tronics systems, which
use a 10k potentiometer as an input
device and produce an output signal
compatible with standard RC servos or
ESCs.
There are two common methods for
using the U/Tronics system for Carrier,
and Clancy produces a single-channel U/
Tronics unit well suited for Carrier. The
U/Tronics controller can be mounted at
the handle with the servo signal passing
through the lines or the unit can be in
the model with the potentiometer in the
handle. Both methods use two insulated
lines for elevator control.
Pete Mazur’s U/Tronics handle is
depicted. He houses the U/Tronics
unit in the handle along with batteries
and connects the potentiometer to the
throttle control of a handle that mimics
the confi guration and feel of a standard
mechanical three-line handle.
In Pete’s application, the signal drives
an ESC directly in a Class I F8F Bearcat
for Class I E-Carrier fl ying. The same
system could drive a servo to control an
internal combustion engine.
Another common practice in
E-Carrier fl ying is to use a standard
mechanical three-line system with the
throttle arm of the bellcrank connected
to the potentiometer as I described in
my July column. In such a system, all of
the electronics are in the model. Contact
information for Clancy Arnold is at the
end of this column.