138 M ODEL AVIATION
CONTROL LINE SCALE
Bill Boss, 77-06 269th St., New Hyde Park NY 11040
Dave DulaItIs (Sun City Center, Florida) is back this month
with his latest project: a Martin P4M Mercator. It is a unique
four-engine aircraft with two reciprocating engines and a pair of
turbojets in the rear of each piston-engine nacelle. The Mercator
was built for the US Navy as one of its attempts to gain the
benefit of high overtarget performance combined with longrange
capabilities with the mixed power-plant combination.
The P4M-1 prototype was ordered in July 1944, and the first
flight of this shoulder-wing monoplane with tricycle retractable
landing gear was made in 1946. The power plants were Pratt &
Whitney 2218 KW R-4360-4 Wasp Major radial engines and
3,825-pound-thrust Allison J33-A-17 turbojets in each nacelle.
All 19 of the Martin Mercator P4Ms, designated as patrol
bombers, served in the Navy Squadron VP-21.
The airplane had a speed of 410 mph, a ceiling of 34,600 feet,
and a range of 2,840 miles. Armament consisted of two 20mm
cannons in the nose and tail turrets, and two .5 machine guns in
the dorsal turret and one on each side of the fuselage. The
airplane could also carry approximately 6,000 pounds of bombs.
The preceding information was obtained from Barnes & Noble’s
The Complete Encyclopedia of World Aircraft.
Dave Dulaitis with his latest Scale project: a Martin P4M-1
Mercator built from plans published in 1954. Dulaitis photo.
The Mercator has two O.S. .10s, spans 52 inches, has throttle
control by standard three-line bellcrank system. Dulaitis photo.
Dave’s model was built from plans found in a Smith & Street
publication (probably Air Trails) in 1954. The Mercator has a
wingspan of 52 inches, weighs roughly three pounds, and is
powered with two O.S. .10 engines that are controlled via a
standard three-line bellcrank system. Whistles were installed in
the rear of the model’s engine nacelles to simulate the sound of
the turbojets.
Dave’s recent letters also contained comments on the number
of Control Line (CL) Scale events we have; he believes we have
too many and that our Scale rules are too complicated for the
beginner. He noted that the Profile event, which is supposed to be
for beginners, permits the use of operational features allowed in
the CL Sport Scale event.
Dave believes we ought to have a beginners’ event in which
models are judged only for static appearance, as is done in Sport
Scale. He thinks the only thing that should be required for flight
is the completion of a 10-lap qualifying flight, with one point
awarded for each lap. No operational features, such as retracting
gear, dropping of bombs, etc., would be allowed. The emphasis
would be on building and detailing a full-bodied model without
having to be concerned about installing operational features.
Dave’s idea might be good for a beginners’ event, but a model
for such an event should also have throttle control and be judged
with a minimum amount of points (possibly zero to five each) for
takeoff, flight glide, and landing.
Besides not having to install operational features, in this event
the beginner would be able to learn the principles of throttle
control for takeoff and landing and fly a model that looks more
like the prototype than a profile model does; such an aircraft
would certainly have more spectator appeal. This type of event
could be used as a stepping-stone to the Sport Scale event in
which operational features have become a requirement.
Local clubs could use Dave’s idea to interest members in
doing something with a Scale model, or they could even try it at a
local contest. If any club takes Dave’s idea and runs such an
event, I would certainly like to hear about it and report the results
in this column.
Dave has questioned the number of CL Scale events, and we
might want to think Continued on page 142
142 M ODEL AVIATION
about whether or not there’s a need to reduce
the number of events. How about combining
the Designer and Precision events to create
the ultimate CL Scale event that would be
judged by Precision rules and require the
model to be designed and built by Designer
rules?
This would reduce CL Scale events to
three: the ultimate event (Designer/Precision)
for the expert modeler, the Sport event for the
intermediate modeler, and the Profile or other
beginner event such as Dave has suggested.
What are your thoughts?
the Cradle of Aviation Museum at Mitchell
Field in Garden City, New York, reopened its
doors to visitors May 13, 2002, on the 75th
anniversary of Charles Lindbergh’s famous
New York-to-Paris trans-Atlantic flight.
The revitalized museum boasts 130,000
square feet of space, the Reckson Center, a
three-hundred-seat IMAX dome theater, an
excellent aviation bookstore that has a great
selection of books (good for documentation)
along with educational toys and gifts all
related to aviation, a café, and 70+ aircraft
and space items on display. The aircraft
include Lindbergh’s Jenny and the Brunner
Winkle Bird he was said to have purchased
to teach his wife Ann Morrow how to fly.
The museum is located on Charles
Lindbergh Boulevard in Garden City and is
open daily from 10 a.m. to 5 p.m. It’s a great
place to take the family or school classes for
a tour and learn something about Long
Island’s heritage as it relates to the
advancement of aviation and space
exploration.
The museum is easy to find. Take
Meadowbrook State Parkway to exit M4,
follow signs to the Nassau Coliseum on
Charles Lindbergh Boulevard. Go to the
second traffic light and turn right into the
museum parking lot. For more information,
visit the museum Web site at
www.cradleofaviation.org.
Wind Canyon Books, Inc. offers three great
books about the Golden Age of Aviation:
Cessna’s Golden Age, Aeronca’s Golden
Age, and Piper’s Golden Age. The books
provide details of the family, people, and
manufacturing operations of each aircraft
company from the early 1900s through the
Golden Age and World War II. Each book is
softbound and has 90-124 pages filled with
history, photos, and three-view scale
drawings, and is in the 81⁄2 x 11-inch format.
Did you Know …
That any donation you make to AMA is tax-deductible?
AMA is a 501(c)(3), not-for-profit association. This means that any funds
you donate beyond your regular membership dues can be deducted from
your taxes.
Please consider donating to AMA. Your gift will help us continue our
efforts to improve your organization.
Wind Canyon has all Paul Matt scale
airplane drawings in sheet form, two books,
and CD-ROM. Also available are Superscale
drawings in 24 x 36-inch format for such
airplanes as the P-47D Thunderbolt, the
Lockheed P-38L, the Spitfire Mk I, and
several others. The drawings include
cockpits, structures, markings, and details.
For the cost and complete listing of books
and drawings, write to Wind Canyon Books,
Inc., Box 511, Brawley CA 92227, or visit
the Web site at
www.windcanyonbooks.com.
Workshop tips: Bob Furr of the Orbiting
Eagles club of Omaha, Nebraska, says that a
close-fitting joint will often bond
satisfactorily under atmospheric pressure
without clamping. You can achieve this by
wetting both surfaces with glue, then rubbing
them together to squeeze glue and air out of
the joining components; this is known as a
“rubbed joint.” Don’t use this method if
there is any reasonable way to get the parts
clamped together to ensure a good fit.
When gluing two sheets of balsa along the
edge, a bead of glue often forms along the
seam that can be difficult to sand. One trick
to minimize this problem is to fasten the
sheets together with wide Scotch tape, then
slice them back apart leaving the tape on the
two pieces of sheet. Once that’s done, tape
the sheet together from the other side as
usual. When you put the glue in the joint
now, any bead that forms will be on the tape
and not the wood.
When the glue is dry, pull the tape off
and the bead of excess glue comes with it,
leaving the sheet of wood almost free of glue
on the surface. You will have little, if any,
sanding to do to smooth the joint.
Please send ideas, notice of upcoming CL
Scale events, contest reports, and especially
photos of CL Scale activity to me at the
address at the top of this column. MA
Continued from page 138
Control Line Scale
