A plane to go with my Depron XB70 Valkyrie

that is cool.

Spent the period over the New Year building the fuselage box and ducts for the 50% bigger XF108.
 
The left hand EDF and nozzle are installed.
Note the "magnet" wires lead through the formers all the way forward where they will ultimately be soldered directly to a Little Bee 20A OPTO ESC. They are small light and produce very little heat but it does mean a small separate  BEC will be required to power the receiver and the two servos (elevons no rudder).  
The right hand EDF will be the same but I am not sure I have enough wire! 
Just for fun a rear view of the nozzle and 12 blade EDF.
 
Soon have to start thinking about the delta wing that will sit on top of the fuselage box.

Off to Liverpool Broad Green hospital first thing for a second "infusion" of Rituximab that hopefully will help my kidneys recover to a satisfactory level.  

Not much to show for several hours work but the green B&Q 3mm foam is dreadful to work with.
 
Both EDFs in and tested. The slow bit is neatly fairing in the two circular exhaust nozzles from what starts as a oblong!
The top surface of the fuselage is quite involved too!
 
To make matter worse not all the drawings show exactly the same!

 

Some modest progress. Made a start on covering the upper surface of the fuselage box.
 
Next will be the fin and a bit of the fuselage spine then the wings.
I have to leave the rest of the top open so I can run the elevon servo wires.
It all rather "work out how to do it as you go along". 

 

Next is the fin and a bit of the fuselage spine.
 
All very light just foam skins with no spar!
That's is about as far as I can go adding top skin. Wing is next.
 The full size appeared to h\ve separate elevators and ailerons. I think I will combine them into elevons if only to save the weight of a pair of servos! 
 

In my usual all sheet foam style. The LH lower wing skin.
 
It is surprisingly small although it does have quite a substantial area wing tip.
I really cant tell at this stage how stiff it will be. May require so carbon 'tow' glued to the top and bottom surfaces. 
 

It now has wings! or at least the inner delta
 
Wing tips and the quite substantial control surfaces still to be added.
I am having a discussion on another site concerning the XF108's long duct why it has no cheat holes.
Trying to explain that with a duct with an area nearly 1.4 times the FSA the object is to maintain the inlet air velocity (its close to the plane's air speed) undisturbed all the way to the fan face. You only need a cheat holes if the inlet  area is too small for the fan that has to be installed for it to fly.
As an example I note the HK Vampire has to have both a way over scale size rear fuselage & exhaust (that on the Vampire's Goblin is particularly small) and big cheat holes to manage its 70mm EDF.
 

 
Whereas my lightweight DH Venom uses a 55mm EDF, has a scale size exhaust (actually its slightly bigger than the Vampire due to the more powerful Ghost) and no cheat holes.
 
Its all a matter of what you are trying to achieve. 
.
 

Still making some progress with the Rapier.
A n elevon servo glued in. The servo is flush with the upper wing surface.
 
It is about 1mm proud on the underside.
 
Note the wing under fins. They are the right length but have been reduced in depth so they do not foul the ground in a belly landing providing you keep the wings level!
 

Ah but keeping wings level during a landing takes a lot of skill if the wind is being unhelpful.... 

As the rest is structurally more or less complete I have a start on the nose section.
To be made as a planked  "half shell over the plan".it will have quite lot of specially shaped planks!
 
Part of the problem is with the EDFs right at the rear I have no idea where the 1400mAh 4s LiPo will have to go, hopefully somewhere under the canopy 
We shall have to see!


 
 

After rather too long the "fuselage" is fully skinned.
 
Not being "the hulk" I was getting rather tired of it being all over green!
This is roughly how it will sit in the rest of the XF108.
 
It will all be painted silver.
I have ordered 2 x 20A Little Bee ESC. They are OPTO (no BEC) but I already have a suitable switching BEC.
My intention is to install the  ESCs and test them before the nose is added. With nose added I should be able to make a reasonable "guestimate" of where the 1400mAh 4s LiPo will have to go.
 

My first impression was it would have given the F15 a run for its money although it would never have been an air superiority fighter!

At long  last I have installed the elevons
 
Although they look divided they are joined by a thin glass leading edge rod which also acts as the pivot at each end and in the middle.Works well and is very free running.
But there is a serious disaster! Somewhere along the line the long servo extensions, both of them, went electrically dead!
They really need to be a bit longer so rethreading new ones all the way though the centre box fuselage will have to wait.
At least the servos are tested and the links adjusted to give the neutral position.