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Posted by JureZ | Sep 20, 2020 @ 11:44 PM | 2,671 Views
Maiden flight of the Ahi glider at Shell Ridge.

Ahi glider at Shell Ridge - Movie (2 min 51 sec)

Posted by JureZ | Aug 31, 2020 @ 12:55 AM | 5,933 Views
Maiden flight of the Alula EVO , at the Shell Ridge slope.
Alula is Latin for winglet or little wing. It is the diminutive of the noun "ala" (wing).
The Alula glider was designed by Michael Richter, manufactured by his company Dream-Flight , https://dream-flight.com/

This plane was purchased , (used) , from my "cousin" Marek S. , and needed some TLC.
It was cleaned , and covered with Doculam , aka "the new stuff".

A lightening hole was added to the vertical stabilizer. AUW is 200g.
I still need to optimize the location of the Center of Gravity.
Wind speed was measured at 8mph.

Note the smoke from the massive ongoing fire.

Alula glider sloping at Shell Ridge - Movie (2 min 27 sec)

Posted by JureZ | Jun 21, 2020 @ 12:43 AM | 12,203 Views
Scratch built Crossbow model airplane.

Motorized version of the Crossbow slope glider , with simplified fuselage , and a KFM4 wing (symmetric top and bottom steps) , 36" wingspan. Dollar Tree Foam covered with doculam, aka "the new stuff".

2204 brushless motor , 25g , 2300 RPM/V . Four Stick motor mount.

5x4.5 propeller 10A ESC, 3S

800 mAh LiPo battery,

2x 9g servos

motor and prop were salvaged from a donated drone "corpse".

original Crossbow thread : https://www.rcgroups.com/forums/show...08-KF-Crossbow

Crossbow - Movie (2 min 48 sec)

Posted by JureZ | May 12, 2020 @ 08:27 AM | 7,830 Views
so finally flew Le Fish at Shell Ridge:

Le Fish Movie (2 min 40 sec)

Posted by JureZ | Apr 15, 2020 @ 08:31 AM | 7,577 Views
Here is my GEV video

Ground effect vehicle - Movie (2 min 54 sec)

some details:
Made with coroplast ( 32cm wide x 41 cm long ) ,

brushless motor 50 g , kv =1100

8" x 4.5" GWS propeller ,

2200 mAh 3S battery.

The vertical stabilizer and rudder are from a Radian Glider.

CG at 24% of the actual wing, (disregard the front side bumpers , they do not count ) , CG is at 13.5 cm from the front bumpers
The wing plank has a 4 degree angle of attack . The thrust line is at 0 degree , i.e. parallel to the ground.
The exhaust section of the duct ( 120 cm^2 ) , is smaller than the intake ( 210 cm^2 ) .

Also, made certain that a large fraction of the prop wash went directly into the lower duct., by lowering the motor as much as possible.
eventually made it into a four wheeler, as shown in the CG picture.
Posted by JureZ | Feb 24, 2020 @ 10:42 AM | 6,594 Views
Posted by JureZ | Feb 13, 2020 @ 10:29 AM | 4,644 Views
bought it from Steve.

2m wingspan, beautiful flyer ! AUW is 600g = 21oz.

Built like a DLG, carbon tube fuselage, lightening holes in the tail feathers, pull- spring drive for rudder and elevator.

EP Glider - Movie (2 min 23 sec)

Posted by JureZ | Dec 08, 2019 @ 07:42 PM | 6,498 Views
here is one more for the collection of Frankenplanes

AUW 990g ,Wing Span 44" , Propeller MAS 10x8 , Motor BL15 , Battery 3S 40C 2200 mAh

Frankenstein Extra Trojan T 28 Movie (2 min 24 sec)

Posted by JureZ | Oct 16, 2019 @ 01:19 PM | 5,583 Views
GWS F-15 , built as pusher with an outrunner motor at the tail , split elevators and ailerons , belly lander .

AUW is 948g or 33.44 oz. Motor is from the Freewing Moray : 3040 , Kv = 1400 , weight = 114 gram ,
3S 2200 mAh LiPo battery.
8*6 MAS S2 propeller , Static current is 19A full throttle.
8*8 APC propeller , Static current is 25A full throttle. (much better choice)

After years in the attic, finally saw the light of day , and got a maiden flight ! great success !

GWS F-15 Eagle - Movie (2 min 8 sec)

Posted by JureZ | Aug 18, 2019 @ 11:02 PM | 5,433 Views
vendor link:

flying at Lime Ridge, Concord , CA. using 2200mAh 40C 3S LiPo battery
Excalibur at Lime Ridge - Movie (2 min 17 sec)

• Highly compressed EPO foam construction
• Nose cone supplied for slope soaring
• Reinforced with carbon fiber and glass fiber
• Extreme speed, Awesome maneuverability
• Bolt together plug and play design
• Unique forward sweep wing design
• V-tail tailplane
• Aerostar 3542 800kv brushless outrunner
• Aerostar 60amp brushless ESC
• Folding 13x7 Aerostar carbon fiber propeller
• Quality Servos
• PCB servo wing connector
• Stunning looks
• Intake cooling features
• Ready to fly in minutes

Wingspan: 1600mm (63")
Length: 1010mm
Flying weight: 1250g
Controls: 4 Channel (Ailerons, Elevator, Rudder (V-Tail), Throttle)
ESC: Aerostar 60amp brushless ESC
Motor: 3542-800kv brushless outrunner
Propeller: Aerostar folding carbon fiber 13x7

Minimum 4ch Transmitter capable of V-Tail mixing
Appropriate 4ch receiver
1 x 1800~2200mAh 4S LiPoly high "C" rated battery

Posted by JureZ | Jul 05, 2019 @ 06:11 PM | 7,512 Views
so, I made a delta with 45 degree swept wings, wingspan is 29" ( 75 cm ) .
inspired by the "Lil Ripper" by goldguy.

used this material which I had available:
  • Dollar Store foam-board, paper off.
  • 2204 brushless motor , 25g , 2300 RPM/V . Stick mount. 5x4.5 propeller
  • 12A ESC
  • 2S 300 mAh LiPo battery
  • 2x Futaba S3114 servos
  • credit card for opposite side of the stick mount. tape and gorilla glue.
AUW is 5.9 oz = 167 g
motor and prop were salvaged from a donated drone "corpse".
They were meant for 3S , but I decided to use just 2S. no need for more power and noise !

maiden flight video
delta Movie (2 min 30 sec)

Delta - second day flying - painted - Movie (1 min 58 sec)
Posted by JureZ | Feb 20, 2019 @ 01:12 AM | 10,354 Views
what I do (borrowed from the 'net)
Posted by JureZ | Nov 17, 2018 @ 11:13 PM | 23,632 Views
here is a video, after switching to a 10g brushless motor (custom rewound, Y , 36 Turns per tooth, wire AWG 33, Kv= 635 ) ,
10 A ESC,
Battery 2S 300 mAh 30C,
APC 7*3.8 SF Propeller ,
FrSky 4 Channel RX.
two UMX Spectrum Linear Servos ,
82g AUW, wing loading = 3.16 oz/sq ft ,
Static test current draw at full throttle : 2.2A @ 8V , 17.6W into the ESC.

Flying outdoors, note the smoke from the "Camp Fire"

micro nutball - 10 g brushless motor - new propeller - Movie (3 min 0 sec)

micro nutball - 10 g brushless motor - new propeller - Movie (3 min 0 sec)
Posted by JureZ | Sep 15, 2018 @ 11:39 PM | 25,667 Views
a gift from Danny , MiG-27 by Carl Goldberg , FQM117-B Military Drone for Target Practice.
Carl Goldberg meets Rube Goldberg.
Recycled using just the wing "Plank Style".

Wingspan: 70 in . Wing Area: 5786 sq cm = 6.23 sq ft . Wing Loading: 8.2 oz/sq ft
AUW : 1400g = 49.8 oz.
Added coroplast vertical fin.
Hyperion HP-S3025-08 motor
Aeronaut CAM Carbon 12"x10" folding propeller.
50 A ESC with separate BEC.
3S 2200 mAh 40C battery.
Two Futaba 3003 standard analog 37 g servos for the elevons. https://www.towerhobbies.com/cgi-bin/wti0001p?&I=LXH288
Taranis QX7 radio
see parts details in the next comment in this thread

Maiden Flight Video
Carl Goldberg Mig 27 Drone (2 min 32 sec)

airborne camera video
Mig 27 - Carl Goldberg drone - airborne camera at Baylands Park Movie (4 min 49 sec)
...Continue Reading
Posted by JureZ | Sep 02, 2018 @ 11:19 PM | 23,327 Views
finally , everything was aligned for a great day of aero towing.
finished and tested the tow release mechanism mounted on the Sky Raiders chuck glider converted to RC.
prepared the twin Bixler 3 , now using APC 9x7.5 props , and installed the landing gear..

using 3S LiPo battery, measured a 40 A peak total current , i.e. 20A at full throttle on each motor , in static test.
10 pound test mono-filament line about 30 ft long.
A red ribbon , looped many times over , did the service of the parachute at the end of the tow line.
The tow release mechanism was home made, can be seen in detail in the video posted below.

of course had a lot of assistance, mainly from Sean and Vishwas.
With Sean we took care of proper CG placement and trimming.
Sean flew the glider and I flew the tow plane.
Vishwas was the ground camera boss.

here is the video:
Baylands Aerotow - Movie (3 min 34 sec)

Baylands Aerotow - Movie (3 min 34 sec)
Posted by JureZ | Aug 25, 2018 @ 06:44 AM | 23,991 Views
this is the EzFly built for my friend Vishwas M.
He is a colleague visiting from Bangalore, who wanted to learn to fly RC planes.
We came to the conclusion that an easily reproduceable and disposable trainer plane would be the the best choice.
He could learn RC flying using the EzFly during his stay here , and will rebuild it ( or another) back home.
He learned to fly very quickly to the point of being able to fly, land and launch all by himself.
Outstanding quick learner ! Congratulations Vish !

Vishwas M - flying the EzFly - second Movie (3 min 52 sec)
Vishwas M - flying the EzFly - second Movie (3 min 52 sec)

https://youtu.be/E5ZZuKdfytE"]EzFly ground based camera - 8-19-18 - Movie[/URL] (2 min 54 sec)
EzFly ground based camera - 8-19-18 - Movie (2 min 54 sec)
...Continue Reading
Posted by JureZ | Aug 02, 2018 @ 08:00 AM | 24,194 Views
Percent Battery Charge monitor, Lua Script for Taranis (tested on the QX7)

OK , here is the package with my script and supporting documentation.
the script is "my_bat.lua" , ( remove ".txt" from the filename).
It should be stored in the memory card under the directory SCRIPTS/MIXES
The script produces an integer number, the Percent Charge remaining.
It may be displayed on the Telemetry screen and may also be read out loud by a special function.
(see screen shot pics of these screens)
The assumption is that there is a Voltage sensor in A2.

The instructions may be followed from the attached file "Model Script Example Automatic Battery Cell Detection.docx " , from where my script was derived .
The table of percent battery charge data was taken from the package "battery_checker.zip"
The XL spreadsheet included in "LiPo_disch.zip" has the cell Voltage - Charge data and charts .

Credit goes to these sources for most of the material I used :
OpenTX- LUA reference guide
Model Script Example: Automatic Battery Cell Detection

Battery Checker Version:4.1

I hope it works for you !

my original post, on the QX7 thread : https://www.rcgroups.com/forums/show...postcount=8630