CONTROL LINE RACING - 2003/06

AS I WRITE this column the roar of racing
engines from Daytona, Florida, indicates
that spring is almost here, and with that
comes another flying season. I recently
attended the annual Tangerine contest in
Titusville, Florida. Some of the events flown
were Mouse II, Quickie Rat, and Fox
Racing.
In Mouse II the usual starting problems
plagued most competitors, resulting in poor
race times, but the airspeed even on the
longer wire was extremely impressive for
some competitors. Bob Whitney has
prepared two first-class airplanes, for
himself and his pilot Dave Hallas. Bob’s
entry suffered this year, but Dave’s was
definitely the class of the field with Cyclon
power.
Dave’s model was consistently
approximately 96 mph in traffic during the
race. The 100 mph mark is not out of the
question, and I would expect to see some
airplanes running that speed at the
Nationals. What makes this even more
impressive is the 10%-nitromethane fuel
being used. Ralph Aaberg finished second,
and Gabe Manfredi took third.
Brian Silversmith came from New Jersey
to do some racing, and he had not only an
unforgettable airplane but an unforgettable
incident. Although it was conventional in
appearance, Brian’s model had an aluminum
brake attached to the landing gear. It was a
piece that formed an upside-down “T” from
the airplane, with the wheel bolted to the
rear of the horizontal piece. The front
worked as a brake during pit stops. By
nosing the airplane over on landing, the
aluminum piece dragged the ground,
stopping the airplane.
This is an old concept, but it needed to
be slightly better conceived. I do not
recommend this horizontal approach. If a
person in the pit crew misjudged a catch just
slightly, he or she could have a piece of
aluminum plate sticking in his or her hand
or some other body part.
The other problem is that it could
become a line-snagger on landing. With the
forward-protruding piece of aluminum it is
easy to see how this could catch a set of
lines, resulting in a catastrophic accident.
Safety is a vital concern at all airplane
contests, and being safe requires that all
participants be alert about what they are
doing at all times.
The second unforgettable event occurred
during the two-minute warm-up. An
incident took place that could have easily
resulted in two people being hurt, and a lost
airplane at the very least. Fortunately Dave
Wallick was holding the handle.
The pit crew had a moment of poor
communication and poor circle awareness.
As the airplane was warmed up, the second
person in the pit crew—whose responsibility
it is to hold the airplane—let it go. Not only
did this take the person starting the airplane
by surprise, but it took the pilot, who then
had a live racer on his hands, by surprise.
If it weren’t for Dave having the handle
in his hand, this could have been a serious
incident. As it was, I think the people
involved were not only humbled by their
lack of circle awareness, but were visibly
shaken knowing what they had done.
Safety is everyone’s responsibility, and
we must all work to ensure that it is 100% in
the forefront of our minds and actions. The
next time you are at the circle, make sure
you are aware of what is going on around
you because others might not be.
Brian went on to win with a time of 5:51.
CONTROL LINE RACING
Dave McDonald, Box 384, Daleville IN 47334; E-mail: [email protected]
Bob Whitney prepares to start Dave
Hallas’s Mouse II entry in Florida. It ran
approximately 96 mph in traffic.
The cut rod in the K&B 4011-series
Quickie Rat engine is showing no signs of
fatigue during testing.
In John McCollum’s engine-testing room, notice the tachometer on an adjustable arm
and the fuel bottle that is adjustable for carburetor height.
144 MODEL AVIATIONJune 2003 145
That was an extremely good time for this
contest, and he will have to repeat it at the
Nationals if he wants to get into the
winner’s circle. Gabe Manfredi finished
second, and Ralph Aaberg was third.
In Quickie Rat I flew Wayne Trivin’s
entry, which was one of the fastest airplanes
at the meet. With a one-flip start and a oneflip
pit, Wayne was able to post a 3:01 in the
first of his heat races. That’s a good time in
this event; it could have easily been under
the three-minute mark with a little luck
flying through traffic.
All of the airplanes are closely matched
in this event, and it usually comes down to
who can outpit the other person to determine
the finalists. In this case, Ralph Aaberg and
Byron Bednar turned in good heat times to
secure their spots in the final with Wayne.
The final was something less than stellar;
Wayne didn’t even get the airplane to start
during the final, resulting in him finishing
third. Ralph claimed first place and Byron
took second.
If you are looking to escape the winter, I
highly recommend that you plan on
attending this event next year; the weather is
usually nice for flying. There are many
things to see and do around this area of
Florida, and you can plan on making a week
or so out of the trip. You can stop at
Daytona Speedway, Walt Disney World,
Cape Kennedy, or visit one of the many
wonderful golf courses in the area.
Testing of new Quickie Rat engines and ideas
became a reality recently. I stopped by John
McCollum’s on a business trip, and we tested
some of the engines in his test room. John has
a wonderful indoor test facility, complete with
a tachometer stand, an adjustable-height fueldelivery
system, and a system to remove the
exhaust from his work area.
I gathered parts during the winter,
including numerous spare pistons and liners
for approximately nine Quickie Rat engines.
During my winter engine program I decided
to document all of the engines; I wrote
down their timing numbers, head
clearances, the type of rods that are in them,
and the vintage crankshafts.
Using the K&B 4011-series engine, I
have observed that there are two basic types
of cranks. The one vintage, which I believe
to be the older type, has a black
counterweight and pressed-in crankpin. I
have found this crank softer and slightly
smaller in inside diameter (ID) than the
newer-type crank. The crankpin is not a
separate item in the newer crank, but is
machined on the crank. This crank is harder
than the older style, and the ID is slightly
larger.
Both cranks can be bored out using a
carbide ball end mill without a problem. The
question is, how far can one go and not
develop reliability problems? I have bored
the cranks out to .385 and have not had any
reliability issues. With a .315 venturi as the
maximum, my idea is not so much making
the crank bigger as it is to make every
moving part lighter. The crank is the first
step.
Second, I have removed material from
the inside of the pistons. This is probably
more work than it is worth, but I wanted to
go the full route in making everything as
light as possible. One of the things I did and
was told, “Oh, it won’t work,” “Oh, it will
break,” etc. was to remove the center from a
conventional connecting rod.
My idea was not only to lighten the rod,
but to try to make the rod run cooler and
reduce the obstruction from the crank hole.
The cooler idea came from the United
Kingdom F2C guys who have done a
variation of this in their F2C engines for
several years without problems. I am
pleased to report that not only did I save
noticeable weight, but I saw a measurable
performance increase in the engine to which
I did this. So far the rod shows no signs of
abnormal wear or fatigue.
Throughout the years K&B has made
many variations on the rod. There is a
debate about the performance of the round
rod versus the conventional type, and unless
you are planning on modifying a stock rod I
suggest that you use a round rod. One thing
you should look at is the rod in your engine;
throughout the years there have been many
different types and construction methods.
Some had bushings; some did not. I do not
recommend using a rod that does not have a
bushing at both ends.
Another modification I am making is to
remove material from under the venturi area.
If you look into a K&B 4011-series front
end, it has a square opening under the
venturi. I have made a fixture and removed
some of the square area to allow me to make
a better fuel-delivery system and still use the
holes in the case for the needle valve. When
done properly, you can remove the entire
front square area and still keep it on both
sides. The sides control the crank’s timing.
I have also recut the heads to allow me to
play with head clearance. If you do this, you
will need to make or find some shims to
then move the head to the desired clearance
range. I am also trying removing some
material from the sleeves, thinning the webs
in the exhaust and transfer openings, and
changing some engines’ timing to determine
its effect on power, range, and the torque
that the engine develops. As testing
continues we will see how these
modifications work, if they work as a whole,
or if only a portion of them are beneficial.
Steve Wilk has introduced a new carbon
landing gear for Scale Racers. These are a
copy of the Glenn Lee landing gear and are
roughly half the weight of the titanium gear.
Initial testing on this gear is proceeding, and
hopefully those results can be shared in the
near future. Steve is making two variations
in the gear: how the gear is made and the
amount of tow or cloth that is used.
My initial reaction is positive, and I
prefer the type with the cloth on the exterior
of the gear. Using a test stand is one thing,
but as the weather gets more conducive to
flying I will be anxious to see how these
work on an airplane during race conditions.
If you are interested in a set of carbon
landing gear or would like more
information, contact Steve at 3257 Welcome
Ave. N., Crystal MN 55422, or E-mail him
at [email protected].
As always, your comments are solicited and
appreciated. MA