The next repair. Depron Airbus A350

Another plane that has been sitting damaged for months is my Airbus A350.
 
This picture was taken at a DVMFC open day in 2019!.
The problem is without U/C it lands on the engine nacelles so every landing has to be a"greaser" or this happens. 
 
In fact over the years both nacelle pylons have been repaired more than once.
This latest break is unfortunately very close to the wing leading edge.
 
It is going to be tricky to fix unless the wing is seriously cut open and the complete pylon and nacelle replaced. It is a complex printed structure built up of many parts glued together.
 

It is not strictly an EDF but uses a ducted "quad" prop and motor inside each scale nacelle. 
Worth repairing if possible as being light for its size it flies very realistically. 

If it's a clean break at the wing/pylon joint - just cyano a cocktail stick or a bit of carbon rod in as a splint.

Eric
The area of material at the break is very small. It is a hollow 20 x 15 mm rectangle (the motor wires run inside) with the walls just 0.45 mm thick! Super glue does stick PLA well but not that well.
The repair will be made by sticking on 40 mm long 0.6 mm thick PLA printed plates that will overlap the break. It should be as strong as the original. The problem will be holding it all in place while the glues sets.
I was very concerned with weight when I designed the original nacelle pylon and should have made the walls in that area at least twice a thick.   
The pylon that holds the motor nacelle is highly stressed as Boeing have found out on the 777X delaying deliveries to airlines to at least 2025. Its original in service date was 2021'  
 

The pylon repair started.
 
With the weight of the motor & nacelle well forward of the break it takes some clamping. Hopefully once the first plates are fixed it will get easier.

The nacelle pylon repair complete and painted.
 
Like everything on these super lightweights it all takes far too long.
All good for now until the next "less than perfect" landing! 

So back to the "improvements"to the Vought 173.

I decided my A350 although complete was starting to look a bit "dog eared" with multiple nicks and even small pieces missing particularly from the wing trailing edge. It needed some TLC.
Whilst thinking about it I commented on a some videos posted showing the XFly TwinLiner.
 
Doing take offs and landings. It uses twin 40mm EDFs. My comment was it was all happening at about 4 times scale speed!
There followed a discussion with me suggesting the TwinLiner must be rather heavy for its size given that flying speed is proportional to a plane's weight.
Apparently there is a "fixed flap" modification that does reduce its minimum speed.
The TwinLiner is about the same size as my A350 which does not use EDFs but much lighter and more efficient quad motors and props.
I posted a video of my A350 flying and landing at rather closer to a scale speed.
As I was starting to work on the A350 I decided to add moving flaps to it to see what the effect might be.
Of course the full size has extending two stage slotted flaps. For simplicity I would use a simple trailing edge flap and limit them to just the inboard section next to the fuselage. Even so they are  quite big.
 
We shall see..
There is another big advantage to me as it will not create yet another plane. I simply do not have room for any more! 
 

I also have that problem! I keep saying that I'll have to learn to crash more often, to make room! 

The flaps installed but still waiting for delivery of the required servos.
 
As is always the way having got this far I can think of a better way of doing it with flaps that would occupy the majority of the trailing edge but it would interfere with much of the cut outs I have already made. 
So on reflection I will leave the flaps "as is" after all this is really only an experiment to see the effect of flaps on what is already a pretty slow flyer for an EDF airliner.

Flap servos installed and tested..
 
Spot the mistake.   

One up, one down? 
 

Of course with an FrSky radio you could switch the flaps to separate channels and reverse them.........

The installation of the servo position is very limited so I will take the easy option and have ordered a servo reverser.
The flaps have to go on a single channel as its only a 6 channel Rx with "dual ail" operating so there is only 1 left!
I will use one of these.
 
 It comes with leads ending in servo pugs and sockets but I intend to soldered the board into one of the servo leads.
Tiny and weighs almost nothing.
 

Now the servo reverser has made its way from China it has had the appropriate flap servo wires soldered to it and installed in the radio compartment on the under side of the A350's wing.
 
It really doesn't take up much room!
When the rudder and elevator servo plugs go in the Rx is full! 
And just to prove it works the flaps do now move together.
www.youtube.com/shorts/sTmXq4-kAEM