As
you probably know, an ounce (symbol: oz) is a mass unit
still used by some tribes who have not enjoyed the
international metric system yet. One ounce approximately
equals 28,35 grammes (Nota: there is another variety, the
Troy ounce, which also approximately equals 31,10 grammes
and could allow some modellers to play with mass
measurements...).
Twenty-eight grammes, did you say? It is less
than 31 grammes (of course...), Miss Daisy's mass, the
mini-Indoor from the Dutch Rick Ruijsink. Nothing more was
needed for the now well known "Twisteuse French team" (J.M.
Piednoir, G. Jumelin et J.Y. Martin) to decide to go down
below this magic number.
Magic? Ounce? oz? The name was then obvious, it
will be "Le Magicien d'Oz" ("The Wizard of Oz") and the
specification very simple: a mass of 28 grammes and a wing
loading of 3 g/dm2 to be a slow-flyer. Why 3 g/dm2? Very
simple! Because 3 g/dm2 equals 1 oz/sq.ft (another barbaric
unit used by the same tribes). A "Magicien d'Oz" to the
power 2 in a way...
Construction
Obviously, you have to keep it light! The
fuselage is a triangular beam (30x20 mm measured at the
leading edge) made of 3 carbon rods (diameter 1mm). Almost
everything else is lamellated, that is to say 3 layers of
5/10 mm balsa and 2 layers of carbon tissue. The frame
(fuselage, leading gear, wing, control surfaces) weighs 10
grammes. The receiver, the speed-controller and the two
actuators are all home-made and weigh 5 grammes total. The
motor (HS80 servo motor) weighs 2 grammes and is fed by 2
NiCd 50 mAh cells and a DC/DC converter (2,2V to 5,5V).
As
you probably know, an ounce (symbol: oz) is a mass unit
still used by some tribes who have not enjoyed the
international metric system yet. One ounce approximately
equals 28,35 grammes (Nota: there is another variety, the
Troy ounce, which also approximately equals 31,10 grammes
and could allow some modellers to play with mass
measurements...).
