152 MODEL AVIATION
IN THE APRIL column I mentioned the possibility of having a
money contest on Monday and Tuesday July 12 and 13, 2004,
immediately following the Control Line World Championships. I
have begun a serious effort to secure funding so that we might offer
a substantial amount of money. My goal is to have at least $3,000 to
divide among the top finishers. This will be a fairly new approach to
Combat. The idea is to use FAI F2D models with AMA Fast
Combat rules.
Andy and Bobby Mears ran a similar contest in Lubbock, Texas,
last year and had a lot of fun. There is a considerable amount of
interest in this event on both sides of the Atlantic. In the United
States, a number of pilots who have never made it onto the US team
are extremely good. There are also those, such as myself, who have
had one crack at the world’s best pilots and would like another
opportunity to fly against them.
It looks as though this will be quite a large contest. Plenty of
Americans will be entered, and it is hoped that the Europeans will
want to have a go at the cash. After every World Championships
there are leftover models galore. Since this will be an open-to-all
event, the mechanics and helpers from the European teams will be
eligible to participate.
If you have not decided to go to the World Championships and
National Championships, perhaps this event will spark your interest.
As assistant team manager for the US, I will be rather busy during
the World Championships and ready to pick up a control handle the
instant it is over.
F2D competitions often end in ties, requiring numerous reflys
with a great deal of wasted time. Contributing to this is the
simultaneous launch and the no-kill-wins-the-match option. The
preparation of two models per bout also contributes to the time
required in processing before the match.
With the use of the AMA Fast starting procedure, the chances of
a tie based solely on airtime are remote. Kills will end the match
instantly. This will save equipment and keep the contest moving at a
lively pace. Also, the long kill zone on F2D streamers
(approximately 9 feet, 9 inches) will make getting a kill a bit easier
than with a regulation 7-foot Fast Combat streamer.
I am getting excited about the prospect of this contest coming
together. This sort of event will have a better chance of attracting
the Europeans than regular AMA events such as Fast and 1⁄2A
Combat will. The pilots will already have equipment that is sorted
out and legal for the event.
One other item of concern is the manpower needed to run a fullon
F2D competition. You need teams of judges and plenty of pit
personnel and jury members. There is considerably less to do with
fewer people for an AMA Fast Combat contest. It’s necessary to
keep the matching board accurate and the win-loss board up to date,
but the judging is fairly easy. I expect that many of the participants
will be called on to judge several matches during the event. Once a
kill is registered, the judging is done. Expect a full report in a future
column.
I wrote about fuel systems and the pros and cons of each type in the
April column. What I did not go into is how to actually use a
bladder fuel system, which is the most commonly employed type for
1⁄2A, FAI, Fast, and Speed Limit Combat.
The first thing you have to do is determine the size of surgical
tubing you want to use. A good source for bladder material is
George Cleveland’s GRS Models at 36 Antigua Dr., Kenner LA
70065; Tel.: (504) 443-4640; E-mail: [email protected].
Another source is Mejzlik Modellbau at Borova 14, 644 00 Brno,
Czech Republic, Europe; Tel.: 011420 5 43218888; Fax: 011420 5
CONTROL LINE COMBAT
Rich von Lopez, 8334 Colegio Dr., Los Angeles CA 90045
Shown are several types of bladders, end plugs, and a ruler so
you can get an idea of the parts’ sizes.
A group of bladders including a couple types of pacifiers.
This shows how long kill zone is with full-length FAI streamer.
06sig5QXD 3/24/04 11:50 am Page 152
4321 8880. Tomas Mejzlik also sells bladders
that are already made and ready to go.
Once you have determined the size of the
material you are going to use, you need to
gather several other things, such as soft
binding wire, end plugs, leadout eyelets, and
regular fuel tubing. You can find most of
these items in hardware stores or in local
hobby shops.
Start building the bladder by plugging
one end with a nylon or metal plug. This will
need to be tied in place with soft wire;
copper or galvanized steel (24 gauge) will
work.
Frank Sims, who used to be a regular at
our flying site, showed up at the field one
day with a batch of nylon plugs that fit
perfectly into the end of the surgical bladder
material we were using. These plugs had a
couple grooves that would allow the binding
wire to grip without slippage. Another
option is to tie a knot at the end of the
tubing. This works well, but it uses a bit of
extra bladder material.
Push a leadout eyelet into the fuel tubing
that you then slip into the surgical tubing
and bind in place as you did the end plugs.
Pete Athans would tie his bladders together
with string that had a drop of cyanoacrylate
glue.
Now you have to determine how long
you want to make the bladder, and that will
depend on how big your bladder
compartment is and how long of an engine
run you want. For a typical store-bought FAI
model, a bladder that holds 3 ounces of fuel
will give you more than enough fuel to run a
full four-minute match and the 1-minute
warm-up period. The Mejzlik and Yuvenko
models have bladder compartments that will
accommodate 3 ounces of fuel.
The bladders that I make use 31⁄2 inches
of bladder material. It is best to know how
long your engine will run on a given amount
of fuel. If your engines run a full five
minutes with just 21⁄2 ounces, that is what
you should use to practice with and to trim
your model.
Once you have built your first bladder,
you will need to test its capacity. I have, in
the past, used water to do this. You must
have a syringe with which to push the liquid
into the bladder. You can purchase 2-ounce
syringes from medical-supply stores, and
they are rather cheap. You can also find
them in hobby shops from time to time.
The syringes come with markings for
ounces and metric liquid amounts, which
will allow you to be precise in your fuel
measurements. Once you have filled the
bladder with the amount of fuel you want,
you can determine if you have too much or
too little bladder material.
The one thing I have not mentioned is
that you will need some sort of device to
pinch off the fuel tubing so that it does not
spray liquid everywhere. Most modelers use
a line connector that has been soldered at the
slip joint with one end cut off. The large
opening of the connector allows fuel to flow
to the engine. Pushing the fuel tubing into
the narrow portion of the line connector
closes off the fuel flow to the engine.
Having a pincher such as the lineconnector
device onboard and part of the
fuel system has its advantages. They are
cheap, easy to make, don’t get lost, are easy
to use, and are there in the event that the
model crashes and you need to stop the fuel
flow immediately.
Several pilots, such as George
Cleveland, Chuck Rudner, and Richard
Stubblefield, have been quite successful
using hemostats or homemade clothespin
pinchers. Many of the Europeans use a
device that is similar to the line connector
except that it is part of the model or bolted
to the engine mount.
The fuel in a bladder is under a great
deal of pressure and can empty in a matter
of seconds. One must always have a healthy
respect for fuel under pressure. Using safety
glasses is not a bad idea, nor is using extra
caution when handling a fuel bladder.
The first time I run an engine with a
bladder, I start with the needle valve closed.
I hook up the bladder and slowly open the
needle valve with the venturi facing down,
until I start to get fuel flow. It has to be a
steady drip. This gets me fairly close to the
actual running setting.
You must pinch the fuel line while trying
to start the engine. The prime will give you
a burst of running so that you can release the
fuel flow to the engine. If it does not catch
right away, pinch the fuel tubing quickly or
you will flood the engine. This takes some
trial and error at first. Once you get the hang
of it, you will be pleased with the results.
Most expert pilots set their engines a bit
on the rich side. To determine this, you will
need to pinch the fuel line for an instant to
see if the engine picks up rpm. If it does, it
is probably good to launch. If the engine
sags, it may be too lean and will need to
open the needle valve a bit. Good luck. MA
Edition: Model Aviation - 2004/06
Page Numbers: 152,153
Edition: Model Aviation - 2004/06
Page Numbers: 152,153
152 MODEL AVIATION
IN THE APRIL column I mentioned the possibility of having a
money contest on Monday and Tuesday July 12 and 13, 2004,
immediately following the Control Line World Championships. I
have begun a serious effort to secure funding so that we might offer
a substantial amount of money. My goal is to have at least $3,000 to
divide among the top finishers. This will be a fairly new approach to
Combat. The idea is to use FAI F2D models with AMA Fast
Combat rules.
Andy and Bobby Mears ran a similar contest in Lubbock, Texas,
last year and had a lot of fun. There is a considerable amount of
interest in this event on both sides of the Atlantic. In the United
States, a number of pilots who have never made it onto the US team
are extremely good. There are also those, such as myself, who have
had one crack at the world’s best pilots and would like another
opportunity to fly against them.
It looks as though this will be quite a large contest. Plenty of
Americans will be entered, and it is hoped that the Europeans will
want to have a go at the cash. After every World Championships
there are leftover models galore. Since this will be an open-to-all
event, the mechanics and helpers from the European teams will be
eligible to participate.
If you have not decided to go to the World Championships and
National Championships, perhaps this event will spark your interest.
As assistant team manager for the US, I will be rather busy during
the World Championships and ready to pick up a control handle the
instant it is over.
F2D competitions often end in ties, requiring numerous reflys
with a great deal of wasted time. Contributing to this is the
simultaneous launch and the no-kill-wins-the-match option. The
preparation of two models per bout also contributes to the time
required in processing before the match.
With the use of the AMA Fast starting procedure, the chances of
a tie based solely on airtime are remote. Kills will end the match
instantly. This will save equipment and keep the contest moving at a
lively pace. Also, the long kill zone on F2D streamers
(approximately 9 feet, 9 inches) will make getting a kill a bit easier
than with a regulation 7-foot Fast Combat streamer.
I am getting excited about the prospect of this contest coming
together. This sort of event will have a better chance of attracting
the Europeans than regular AMA events such as Fast and 1⁄2A
Combat will. The pilots will already have equipment that is sorted
out and legal for the event.
One other item of concern is the manpower needed to run a fullon
F2D competition. You need teams of judges and plenty of pit
personnel and jury members. There is considerably less to do with
fewer people for an AMA Fast Combat contest. It’s necessary to
keep the matching board accurate and the win-loss board up to date,
but the judging is fairly easy. I expect that many of the participants
will be called on to judge several matches during the event. Once a
kill is registered, the judging is done. Expect a full report in a future
column.
I wrote about fuel systems and the pros and cons of each type in the
April column. What I did not go into is how to actually use a
bladder fuel system, which is the most commonly employed type for
1⁄2A, FAI, Fast, and Speed Limit Combat.
The first thing you have to do is determine the size of surgical
tubing you want to use. A good source for bladder material is
George Cleveland’s GRS Models at 36 Antigua Dr., Kenner LA
70065; Tel.: (504) 443-4640; E-mail: [email protected].
Another source is Mejzlik Modellbau at Borova 14, 644 00 Brno,
Czech Republic, Europe; Tel.: 011420 5 43218888; Fax: 011420 5
CONTROL LINE COMBAT
Rich von Lopez, 8334 Colegio Dr., Los Angeles CA 90045
Shown are several types of bladders, end plugs, and a ruler so
you can get an idea of the parts’ sizes.
A group of bladders including a couple types of pacifiers.
This shows how long kill zone is with full-length FAI streamer.
06sig5QXD 3/24/04 11:50 am Page 152
4321 8880. Tomas Mejzlik also sells bladders
that are already made and ready to go.
Once you have determined the size of the
material you are going to use, you need to
gather several other things, such as soft
binding wire, end plugs, leadout eyelets, and
regular fuel tubing. You can find most of
these items in hardware stores or in local
hobby shops.
Start building the bladder by plugging
one end with a nylon or metal plug. This will
need to be tied in place with soft wire;
copper or galvanized steel (24 gauge) will
work.
Frank Sims, who used to be a regular at
our flying site, showed up at the field one
day with a batch of nylon plugs that fit
perfectly into the end of the surgical bladder
material we were using. These plugs had a
couple grooves that would allow the binding
wire to grip without slippage. Another
option is to tie a knot at the end of the
tubing. This works well, but it uses a bit of
extra bladder material.
Push a leadout eyelet into the fuel tubing
that you then slip into the surgical tubing
and bind in place as you did the end plugs.
Pete Athans would tie his bladders together
with string that had a drop of cyanoacrylate
glue.
Now you have to determine how long
you want to make the bladder, and that will
depend on how big your bladder
compartment is and how long of an engine
run you want. For a typical store-bought FAI
model, a bladder that holds 3 ounces of fuel
will give you more than enough fuel to run a
full four-minute match and the 1-minute
warm-up period. The Mejzlik and Yuvenko
models have bladder compartments that will
accommodate 3 ounces of fuel.
The bladders that I make use 31⁄2 inches
of bladder material. It is best to know how
long your engine will run on a given amount
of fuel. If your engines run a full five
minutes with just 21⁄2 ounces, that is what
you should use to practice with and to trim
your model.
Once you have built your first bladder,
you will need to test its capacity. I have, in
the past, used water to do this. You must
have a syringe with which to push the liquid
into the bladder. You can purchase 2-ounce
syringes from medical-supply stores, and
they are rather cheap. You can also find
them in hobby shops from time to time.
The syringes come with markings for
ounces and metric liquid amounts, which
will allow you to be precise in your fuel
measurements. Once you have filled the
bladder with the amount of fuel you want,
you can determine if you have too much or
too little bladder material.
The one thing I have not mentioned is
that you will need some sort of device to
pinch off the fuel tubing so that it does not
spray liquid everywhere. Most modelers use
a line connector that has been soldered at the
slip joint with one end cut off. The large
opening of the connector allows fuel to flow
to the engine. Pushing the fuel tubing into
the narrow portion of the line connector
closes off the fuel flow to the engine.
Having a pincher such as the lineconnector
device onboard and part of the
fuel system has its advantages. They are
cheap, easy to make, don’t get lost, are easy
to use, and are there in the event that the
model crashes and you need to stop the fuel
flow immediately.
Several pilots, such as George
Cleveland, Chuck Rudner, and Richard
Stubblefield, have been quite successful
using hemostats or homemade clothespin
pinchers. Many of the Europeans use a
device that is similar to the line connector
except that it is part of the model or bolted
to the engine mount.
The fuel in a bladder is under a great
deal of pressure and can empty in a matter
of seconds. One must always have a healthy
respect for fuel under pressure. Using safety
glasses is not a bad idea, nor is using extra
caution when handling a fuel bladder.
The first time I run an engine with a
bladder, I start with the needle valve closed.
I hook up the bladder and slowly open the
needle valve with the venturi facing down,
until I start to get fuel flow. It has to be a
steady drip. This gets me fairly close to the
actual running setting.
You must pinch the fuel line while trying
to start the engine. The prime will give you
a burst of running so that you can release the
fuel flow to the engine. If it does not catch
right away, pinch the fuel tubing quickly or
you will flood the engine. This takes some
trial and error at first. Once you get the hang
of it, you will be pleased with the results.
Most expert pilots set their engines a bit
on the rich side. To determine this, you will
need to pinch the fuel line for an instant to
see if the engine picks up rpm. If it does, it
is probably good to launch. If the engine
sags, it may be too lean and will need to
open the needle valve a bit. Good luck. MA
