Since I fly using either a 582 Rotax, or
the 912 four stroke, which both use radiators the same as my car
for cooling and heating I figured there must be some way of
easily and economically hooking heat up on my trainer.
into it I found that there were several problems.
I had to find a heater that worked and
- readily available
- had to be adaptable to fit into the
Rotax cooling system
After spending about $700 bucks, on
various R & D projects a system that fits all of the above came
together. The system shown here is very compact.
fact it fits right up under the dash of the L'il Buzzard.
- It comes in at about 10 lbs. with all
the hoses attached.
- Has a two speed fan plus three warm
air outlets which can be opened or closed.
- It can be purchased from L'il Hustler
Ultralight aviation .
- While the outlets on the heater are
1/2" inside diameter and the hose on the 582/912 are 1 inch
the hoses can be adapter to fit into the system using the
following plumbing supplies available from any supply center.
- 2 - 3/4 inch to 1/2 inch copper T
- 4 - 3/4 inch copper couplers
- 2 - 1.2 inch copper couplers
- 1 foot of 3/4 inch copper pipe
- 1 foot of 1/2 inch copper pipe
- 4 hoses clamps for 1 inch hose
- 4 hoses clamps for 1/2 inch hose
- soldering paste (kester)
- sand paper
- thin gauge wire
- pipe cutters
- propane torch
- wire strippers
Use the pipe cutters to cut off 4 pieces
of 3/4 inch copper about 1 inch long and 2 pieces of 1/2 inch
copper about 1 inch long . Use the sand paper to clean these, to
remove any foreign material
With them clean apply solder paste to
the inside of the 3/4 inch T's and to the outside to the pieces
of 3/4 inch copper pipe. Use the propane torch to heat them up
and solder them into place. Once you have soldered them install
the 3/4 inch couplers onto the stubs sticking out of the T's.
Now solder the couplers.
Now strip a piece very thin piece of
wire so that you have about 6 inches of bare wire in you hands.
Wrap it tightly around the top of the 3/4 inch coupler, and then
lightly solder the wire using a propane torch. Use a file to
make the soldered wire smooth and round. This now gives
something for your hose clamp to grip when you tighten it.
Note: without this you
may find yourself having to land in a farmers field like I did
when the hose blew off!
Repeat this procedure for all of the
ends. There you now have a "T" and a reducer to connect into the
cooling system. Hooked up this way the heater will only heat up
to the engine temperature, and you will find that once you turn
the heater on the engine will run cooler.
To maintain a constant 160 degrees -
which is where the engine should be running you now have to find
a way to change the airflow into your radiator. We do this on
the L'il Buzzard by having a little hand crank in the cockpit,
which is attached to the radiator. As the temperature drops we
raise the rad up, out of the airflow, until the desired
temperature is reached.
While this is MY preferred way of
maintaining a constant temperature - other customers have
installed a shut off valve in the main line just after it comes
out of the cylinder head. They connect this via a rod to the
inside of the dash where the rod is pushed back and forth,
either restricting or opening the flow out of the cylinder head.
Now install the "T"'s into the main lines. Connect the smaller
heater hoses into your heater. Clamp all lines securely.
Hook up the electrics to you heater,
making sure you have a good ground. On planes made of
composites, or in others where a ground is not readily available
you may have to run a line back to the battery. If you are using
the heater that I mentioned above it has two speeds - you will
need a two speed switch. Or you can hook up only the fast side .
With all your hoses connected refill
your rad with a mixture of 50% DISTILLED WATER and 50%
anti-freeze. (For the 912 it is necessary to adjust the mixture
to 80/90 % antifreeze depending on the aircraft engine
installation) Start the engine up and let it run for a few
minutes. Check your anti-freeze level you will generally have to
add more to allow for the extra fluid filling the lines and
To purchase this heater click here.
To fly with a heater safely there are
two things that have to be used:
- On the two stroke
engines you MUST use a thermostat to help maintain engine
- You MUST have some
way of adjusting the temperature to compensate for the added
heater cooling effect and colder temperatures outside. This is
in ADDITION to the thermostat.
Click here for Thermostat pricing and installation