Construction / tuning:

Finally, mid of Jan 2011 I started with the building phase of this project:

1) Wing preparation for the fans
The motor housings for the prop motors needed to be removed - so with a sharp balsa knife I first removed the larger parts, then with sand paper - 120 followed by 240
and final with 300 (entire wing) I finished off this proceedure.
The fans will be in stalled in the remaining cable channel as this provides a perfect alignment for the installation.










2) The undercarriage - main section:
I decided to build a "heavy load" 8-wheeler undercarriage: 2 steerable front wheels and 2x3 main wheel section! The wheels are 50 mm dia foam super light wheels.
And the connecting wire (axles) is from 2 mm dia steel.
The base plate is from hard balsa 8 x 12 cm and 5 mm thick, 3 mm thick hard wood rods were cut to hold the wires in place and all was glued together with 5min 2
component epoxy.









The front steerable wheels are
half housed inside of the fuse-
lage . The pictures just show
the trial assembly of the set
of main and front wheels. Of
course they will be properly
glued in with supporting wood.



3) The EDF coils (wing EDF connection)

For that I purchased hard wood 5 x 20 x 100 mm in size - that fits flush
into the cable channel at the bottom of the wing. Then I measured the
distance of the EDF wholes (actually screw mothers) that take the screws
and drilled the wholes in the wood. Now I was able to fix the EDF on the
first wood. On top, at 90 degree I glued with epoxy the actual connection
to the wing - however first I carved out with a Dremel the part where the
screws are covered and then also two additional holes that hold 3mm
dia and 5 cm long CFK rods - these will absorb the forward thrust of the
fans.
In addition two 1 mm CFK rods are glued into a vertical hole that I drilled
through both woods, which also helps to ease the thrust forces on the
glued parts. Beside see the pre-assembled EDF holder (not glued yet).
At the end I finished all by sanding the edges round and ensuring a bit
more aerodynamic look & feel.


The steerable front wheel:

The steerable front wheel was first screwed
to a block of ply wood and then glued into the
fuselage. The steering is made by the rudder
servo (which is a strong metal gear servo).


The finishing touch....

Well, I actually decided to give this plane a "golden" look and used Oracover-stick foil to apply the golden colour! That work was NOT EASY! all the curves, rounds, etc.
and unfortunately I did not manage to get the entire plane "wrinkle-free"!

Sorry folks!

But now the plane is finished and next is the balancing and the rc
programming. And last but not least ... after almost three months
of building (ok...interupted by work... :-) )

... flying....
RCSKYLINER.com
Site for radio controlled airplanes and more ...
NAME:
 
TWIN STAR 2 - EDF (2x Ducted Fan)
PRODUCER:
 
Multiplex
TYPE
  all parts in foam (Elapor)
WING SPAN:
 
1420 mm
LENGTH:
 
1085 mm
WING AREA:
 
40 dm2
WEIGHT PER DM2
 
36 gm / dm2 (estimated)
WEIGHT (producer):
 
1500 g
ACTUAL WEIGHT:
 
1500 g (estimated)
MOTOR:
 
2x Robbe 2835/12
MOTOR DATA:
  Inrunner / 83 g / 300 W / 27 A / 2650 rpv
FAN:
  Vasa, 68 mm dia, 6 blades, incl. housing
BEC / CONTROLLER:
 
2x Robbe (45 A)
RECEIVER:
 
Futaba 2,4 GHz (7-channel R-617 FS )
BATTERY:
 
Robbe Lipo 3200 mA or 5000 mA / 11,1 V
CHANNELS:
 
6 (motor, rudder, elevator, 2x ailerons, 1x
video)
SERVOS USED.
  all: 4x Hitec HS-82 MG
RATING - BUILDING:
 
this version: professional
RATING - FLYING:
 
intermediate & professional
All rights reserved by rcskyliner.com and its owner!
Sorry, no video available yet. Other videos you will find here!
Flight Experience:

End of May 2011 - the first flights have been made. As the grass on our runway was (as usual) too high for the small wheels I decided to hand launch the Twin Star 2
EDF. A bit wobbly in the knees as no fellow pilot was there to help, but after all pre-flight checks I took the Twin Star to its elements.
What a surprise... it flies, and not bad. The sound is great and the two EDFs are handling the plane very well. Even when the wind picked up strongly and most of the
other planes stayed on the ground I flew this Twin Star mod. The first flight lasted 6 min and 20 seconds and I loaded 1200 mAh to the Lipo which was not warm at all.
Also the motors showed no sign of head emission and the BECs stayed cool.
Only the front wheel collapsed during the first taxi back from the runway - more due to the fact that our grass field is in rather "bad" condition.
The next three flights I managed without front wheel and actually decided to leave the wheels away for good - back home I will take away the other landing gear too.
In addition I will change the angle of the EDFs slightly downwards (presently they are fully straight) - as they pull the plane up while running at full speed.
Bye the way, bit less then half throttle is enough to keep the plane up and level - thats why I theoretically could manage to run it over 20 minutes with limited throttle
stick usage.
Great mod for calling attention at the field!