|Construction / tuning:
Actually I had enough planes, but at one of the online visits to a shop
(Modellbau Boehm) I found a reasonable offer in the sale section this little
model. Yes, I know, since 2007 Multiplex is not producing this plane
anymore, and now we have 2010 (when I bought it).. but... for less then 50
Euro, I had to get it!
Stock motor (Permax 400, 6 volt) was put in the drawer because I
purchased a Multiplex motor set for the Easy Cub (has a wingspan of
1400 mm) - so that must work, I thought. The motor was mounted on a
plywood (hardened with epoxy & glass fibre) fire wall which I glued in
some cut out section of the original motor mounts.
The 7 or 8 degree V of the wings was totally eliminated by adding a
plywood part in the middle (at the junction of the wings) and the whole
connection of the wings was strengthened by additional glass fibre and
epoxy. The wooden wing reinforcement was replaced by a 10 mm dia CFk
tube (full length of 1 meter was used).
In order to give good maneuverability I added ailerons (stock plane is only
controlled through rudder and elevator). 4 x 20 cm was cut out - this gives
enough surface for great flying control.
The wheels (45 mm) were replaced with 120 mm ultra light (and big)
ones! Looks now like the Piper-Cub Alaska version with tundra tyres! But
as you may know, we start and land on (bad) grass and for that, I just
need these big ones.
Also the wheels were fixed to a sheet of hard plywood that I saw out in
order to cover the battery & controller part at the bottom of the plane.
Originally this area was totally open and I did not like the thought of
loosing the battery during a bumpy start or touch 'n go maneuver. To
complete the plane it got also a fixed tail wheel.
The yellow paint is stock!
First flight: March 10, 2010
Well I did not expect this. Already when standing and applying half power
the tail lifts off the ground and after 1 meter (yes - ONE METER) the plane
lifts off! What a spectacular start for the first flight! Colleagues were
clapping their hands and cheered...! No, it is really not fast, but powerful,
goes vertical, hovers, roles, loops, turns,.... BUT inverted flight is almost
impossible due to the wing profile (it is slightly inverted).
The only weakness is the 1 mm steel wire that holds the wheels - several
times the whole construction collapsed (see the first video at the end). It
is funny but makes touch and goes almost impossible. Well, that still
needs fixing...during next winter season!
This is a fun plane I am proud of and hopefully we will have lots of flights
together in the future.
Ailerons: 50 % differential
Ailerons & rudder mix: 30 % rudder support for ailerons
Update- May 25, 2010
The "flimsy" wire landing gear was replaced by a CFK gear - much more
stable. Visible in the 2nd video!
Update - December 9, 2011
After some stunt flying I landed the plane on the nose - the motor holder
was broken - so I fixed a new one -using a left over Multiplex Easy Glider
Pro motor mount. After cutting away some foam, adjusting the mount was
easy. With 90 min Epoxy I glued it together and let it dry overnight! As good
as new! Of course I had to check the right and down angle of the motor to
keep the plane from pulling to one side!