The GFS-UAV model N-01A

A Coanda effect flying saucer
created on March 10, 2006 - JLN Labs - September 15, 2006
Toutes les informations et schémas sont publiés gratuitement ( opensource ) et sont destinés à un usage personnel et non commercial
All informations and diagrams are published freely (opensource) and are intended for a private use and a non commercial use.

You will find below the full plan of the GFS-UAV model N-01A and a detailled tutorial to help you to replicate my GFS UAV...

Click here to see a 3D view video about the GFS-UAV N-01 design (1.6 Mb)

Below, the specifications and the performances of my GFS-UAV N01A (the smaller model).

The engine is a brushless motor AC 28/7-30 D brushless motor from MP JET.

Number of cells 6-9 or 2-3x LiPol
RPM per Volt 1100
Maximum recommend speed (min-1) 12000
Maximum speed (min-1) 15000
Maximum efficiency (%) approx. 79
Current of maximum efficiency (A) to 15
Short time currrent (A) 20
Internal resistance Ri ; (mW - miliohm)
Dimensions - diameter/length (mm) 35,5/33
Shaft diameter (mm) 3
Number of turns 30
Weight of drive unit (g) 56
Recommend propeller range APC 7/3 - 9/6 (10/4,7)

The brushless motor is connected to a speed controler JETI Advance 30-3P

The best propeller tested is an APC Electric 10 x 7 E from Landing Products.

The material required to build the GFS-UAV N-01A is a 3 mm thick styrofoam sheet XPS (Depron, Gediplac, Ectrupor) and some 1 mm diameter carbon rods.
click here to see some technical infos about the Depron Foam )

The first step is to print the 35 pages below in PDF and assemble them so as to build the plan at full scale.

Click here to download the full plan of the version 1.0 of the GFS-UAV model N-01A

Above all the GFS-UAV parts must be cut in the styrofoam with a brand new cutter and with a low angle of cut.

To glue the different parts, I recommend you to use UHU Por or special foam Cyanoacrylate (CA) glue.

Above, after a computer designed phase, below, the true model is now a reality (below).

The curved petals, the key of the Coanda effect, are carefully assembled and glued on the main structure.
Be carefull to avoid cracks on the curved surface,
click here to see the method to roll the petals on the main structure.

The GFS-UAV N-01A hull is now finished and perfectly in line with the CAD design...

The four moving flaps are ready to be assembled on the hull with an adhesive tape as hinge.

The moving and fixed rudders for the yaw and the anti-torque control are prepared and installed.

Above: A detailled photo about the main electronic parts (receiver, gyro, Lipo battery, the pitch and bank servos)

Above : A detailled view about the command of the flap.

Above : A detailled view about the command of the moving rudders.
There are 4 servos in parallel controled by the anti-torque piezo gyro for the yaw control (see below)

The ready to flight weight of the GFS-UAV N-01A is 533 g with a video camera transmitter on board.

I recommend strongly to add a streamlined body 280 mm diameter and 60 mm height and placed at 45 mm above the hull. You will notice that the efficiency will be greatly improved and the flight more stable. The streamlined body is made with a 3 mm thick depron foam and fixed with 8 carbon rods (2 mm diam) on the hull.

Above, you will find the correct setup for the all flaps.

I also recommend you to use at least a 150 Watts brushless motor with your GFS-UAV N-01A.

The best engine tested for the GFS-UAV N01 is the outrunner brushless motor : AXI 2808/24 with
a propeller Graupner ECO CAM PROP 10/6" ( 25/15 cm ) ref : 2941.25.15

AXI 2808-24
High torque brushless motor
with rotating drum and high power neodym magnets

Voltage range 4-10 cells
RPM per Volt 1,160 RPM/V
Max. Efficiency 82%
Max. Efficiency Current 6-15 A (>75%)
Max. loading 22 A / 30 s
No load Current/8V 1,0 A
Internal resistance 115 mohm
Dimensions 35x31 mm
Shaft Diameter 4 mm
Weight 76 g

The Lipo battery used is a PowerHouse (selected cells) 3S1P at 11.1V 950mA (rated for 25C)
Lipo pack weight : 96 g

If the video doesn't start itself, click on the "Refresh" button on your internet browser
Click here to download the video (1.5 Mb)

See also :

For more informations, please contact Jean-Louis Naudin :

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visitors since March 18, 2006