|Oct 12, 2014, 11:39 AM|
A350 70mm EDF 1:40scale scratchbuild
Hi to all my fellow modelling enthusiast!
A little background
I felt a huge urge to kick start my new scratch-building project after watching couple of short clips on the actual Airbus 350 from it's initial design stages to it's maiden flight. The A350 will serve as a competitor to Boeing's 787 to compete in this long range,low fuel consumption and composite material build era. As there are numerous discussion between Airbus and Boeing competitiveness, I am not favouring either sides, i'm just a humble scratch builder who likes to build rc-models.
I would like to share this build with all of you,in an attempt to build a RC A350-900 from scratch till it's maiden flight just like how Airbus did it but the only draw-back will be, this is going to be a one man team.
You may help me to provide any positive or negative feedbacks in anyway possible that will aid and improve areas such as building techniques, materials,electrical components,painting methods and whatnot. I'll also be happy to answer any questions asked along the way.
This will be my 4th Airliner build till date,
4)A350-900 (Year2014) <-- New build
Scale - 1:40
Estimated Weight- 2000Grams (70.55oz)
Wing Area - 2.47 ft²
WingLoading - 28.47oz/ft²
Cubic WingLoading - 18.08oz/ft³
Thrust - 1300 grams static (45.85oz)
Main wing Airfoil - Clark Y
Vertical and Horizontal Stab Airfoil - NACA0008
ESC - 40Amp Turnigy x2
EDF - Changesun 10 blade 70mm x2
Motor - Turnigy L2855-2800 EDF Outrunner x2
Retracts - Turnigy Alloy Servoless Airliner Retracts w/Sprung Oleo Legs - Base Light Version (767)
Retracts Sequencer - ASSAN Adjustable Retract and Door sequencer w/Display
Servos - HXT900 9g / 1.6kg / .12sec Micro Servo x13
Strobe Light Controller - Arduino Nano V3.0 Microcontroller Board
Battery - Any brand 3s 4000mah - 6000mah Range of Lipo
Control Surfaces as per channel on the receiver
I've throw in some other redundant add-on goodies that won't be of much help in a model in this scale, but it will make it look even more realistic! (Items 5,6,7,8)
1 - Ailerons
2 - Elevators
3 - Throttle
4 - Rudder coupled with Nose gear steering
5 - Retracts with Door open and close sequencing
6 - Flaps (Fowler flaps identical to the real A350)
7 - Spoilers
8 - On-Off Navigation lights
Other relevant information
-Model will be build out of Blue Foam and EPS ,after which it will be fully fiberglassed
-Model will be painted with Singapore Airlines livery
I have set myself a modest dead-line for this project of 1 year as i have other commitments on day to day basis. Started in Early September 2014 this project will end on Early September 2015. Anything earlier will be a bonus!
Enough said, let the scratch-building begin!
|Oct 12, 2014, 12:04 PM|
Month of September 2014
So far,what I've done in the month of September 2014 was getting ready the some basic preparation such as drawing out new plans on Autocad. The actual A350-900 plans was taken from Airbus's website and i spent over 3 weeks on heavy editing to ensure the main components such as the Retracts with doors and the 70mm Changesun 70mm EDF fits nicely and to scale.
The most important part now is to tackle for now will be getting the retracts to swing in and out with the gear doors opening and closing without any issues of space constraints or restrictions.
In the past, to figure out the CG for every new scratch-build plane i've build. I use to have a link to a website where it scans the entire plan-view area and will give a good gauge on the actual CG location. But unfortunately the website either shifted or closed down. My new method now is to build scaled down chuck glider and use trial and error to find out the new CG by tossing it straight and level in the air and achieve a good glide-ratio without stalling or being nose-heavy.
|Oct 12, 2014, 12:30 PM|
I've started working on the strobe lighting effect not too long ago.
The Arduino Uno Board is chosen to program the lighting effects as i have much more versatility in determining the delay and frequency of each strobe. The Arduino Nano Board will be used in the A350 as it is much more compact and lighter.
I've been watching different airliners such as A380, A320 and B777 at night with different types of pulse-pattern. Honestly, I do not know which type of Strobe patterns the A350 will use. Do anyone know?
I have came up with 2 types so far (see the video)
|Oct 12, 2014, 04:01 PM|
Cool, the neat thing about the A350 and the B787 is there is documented airshow routines that will work very well with correctly powered model airliners.
|Oct 14, 2014, 04:54 AM|
Thanks,thats some motivational information to keep me going!
Anyway i have found how exactly the A350 blink sequence looks like.
It's pretty similar to my "stobe effect 1" where it goes:
white strobe flash x2 followed by anti collision lights flash x1
I'll just need to make minor adjustments accordingly to change the flash-timings to match the real thing.
-There are 2 anti collision lights,one on top of the fuselage,one at the bottom
-There are 3 White strobes , 2 at each wing tip pointing forward and one at the rear of the fuselage
|Oct 14, 2014, 10:03 PM|
Joined Nov 2013
Since you are kinda going nuts on the whole strobe light thing, practically everyone uses the "auto" mode which turns on the strobes with weight off wheels (WOW) and turns then back off on touchdown. FWIW.
|Oct 15, 2014, 08:45 AM|
That's interesting. Didn't know such concept existed. Thanks for sharing.
But I'm going to keep it simple which is to assign a master switch to completely turn on or off the entire lightning system.
|Oct 26, 2014, 12:03 PM|
Programming a Gear-Door Sequencer
Normally handling projects this size,It would be almost with certainty there will be some roadblocks ahead.
I just bump into one huge road block just recently and took 2 weeks to solve it.
I've ordered an Assan Gear-Door sequencer a few months back (see picture) ,plugged in the retracts and servos and it did exactly what it's suppose to do. But after a few runs, the Sequencer just blacked-out on me, everything stopped working. I re-traced back my steps and re-checked all voltages levels given are appropriate and wires connecting to the correct pin and all seems right. i guess i could have end up with a faulty equipment...
I ordered another Assan Gear-Door sequencer and waited for it to ship to my home, this time with utmost caution, triple checking every wire and connections , it went dead on me again after a few runs! , not wanting to order my 3rd piece, i decided to go the extra mile and program my Arduino Uno to do exactly what the Assan Gear-Door Sequencer does except the part where i have to flick the switch 3 times to arm.
Programming also gave me full versatility to adjust my servo-travel, servo sweep delay and door open delay timings. Anybody who owns Arduinos at home and wish to give my code a shot, do let me know in this thread,i'll be more than happy to share.
Theres a thread i've been reading through to seek some help but found out that most guys there are either having problems understanding the manual or finds the "arming" switch quite unesscessary:
Thankfully , now that the gear-door sequencer ,lighting and other electronic issues are resolved, i can now move on to the actual scratch-building phase.
Here is my video on my Arduino-Gear-Door Sequencer.
|Oct 27, 2014, 05:09 AM|
Hey Demondriver, you're not the only one! Even other users found it so difficult to understands the "Translated-Chinese to English words"
So somebody actually took the liberty to rewrite the whole manual into understandable English! I can't remember how i found this,but i would like to share it out to who ever is using the Assan-Gear-Door sequencer to make their life easier!
|Category||Thread||Thread Starter||Forum||Replies||Last Post|
|For Sale||Dynamically balanced Dynam 70mm EDF motor fan unit||The Don||Aircraft - Electric - Jets (FS/W)||5||Oct 02, 2014 12:39 PM|
|Sold||Lander 10 Blade Alloy DPS 70mm EDF unit - 4s 3000kv 1200watt||voxel||Aircraft - Electric - Jets (FS/W)||5||Sep 27, 2014 07:51 PM|
|Build Log||MIG 1.44 Mfi-1:15-70mm EDF||mesnick||Scratchbuilt EDFs||16||Jun 26, 2014 03:24 PM|
|Build Log||SAAB JAS 39C 1:10 scale for 70mm fan. Scratchbuild MAIDENED VIDEO INSIDE||marell01||Electric Ducted Fan Jet Talk||151||Jul 13, 2013 07:24 AM|
|Build Log||SU-37/33 foamy for 70mm EDF Scratchbuild||CarreraGTSCS||Foamy EDFs||125||Sep 01, 2009 09:12 PM|