Peter’s Sikorski throwing up some
spray during its take-off run.
Peter Graeber’s Sikorski S43TRS-1 is a true
amphibian. It has working retracts. The large
2600 span model weighs about 8 kg and is
powered by two Turnigy 4260-500 motors
running off 5S 4900 batteries.
ELECTRICITY & WATER
Mention electricity and water together and most
people think of electrocution and a variety of other
nasty outcomes. Fair enough too. String a few extension leads together and use them outside in the
rain and you might find that your life expectancy
isn’t too good at all. In model flying however, combining electricity and water can lead to some real
fun. I’m talking about electric float-planes and flying boats here of course.
Flying off the water can be really enjoyable.
Seeing your model skimming across the water,
throwing spray to either side then gently climbing
away, leaving behind a glistening trail of water
droplets, is really something to behold. Watching
the model gently caressing the water before settling back into it on a perfect landing can be quite
a thrill. Of course, it’s not always like this. Water
can be a challenging environment to fly off. One of
the big issues for the IC powered models is getting
them back to shore without the engine quitting. It
doesn’t take much spray entering the engine’s carburettor to cause a glow or petrol motor to stop,
particularly when it is idling. I once had a great time
flying a friend’s glow-powered float plane off a lake
but keeping the motor running, particularly during
and after landing, was difficult. With electric power
you don’t have this problem. As long as your aircraft remains upright, you should have no trouble
taxiing it back to the shore.
A simple arming plug and socket can be made from a pair of XT60, Deans or similar connectors.
The female end breaks the positive lead to the ESC. It is mounted in the fuselage, flush
with the outside. The male, with its shorting wire is plugged in to complete circuit.
Karl Kuljurgties flew one of the many Polaris delta-wing flying boats at the
Float Fly. His was built from a kit by Tony Gyoles (as TG Concepts). The
model’s Turnigy 2826 220 motor turns a 6x4 prop on a 3S battery and draws
about 30A at take-off power. Karl wisely uses a 40A ESC, so that it is working
well below its maximum current, as there isn’t really any cooling airflow over it.
There was a mass take-off of Polaris at one stage, with half a dozen or more
rising off the water simultaneously. Ah... the reliability of electrics.
36
Airborne
This ST Model DH Beaver was reviewed in Airborne number 246.
It’s a 1500 mm span ARF that only requires a 3S battery. It performed
impeccably on Lake Hume.