Ride of the Valkyrie?

Ha!
If I was going to build one (but the same conditions still apply! ) it would probably be like this.

The duct would be built in exactly the same way as the one I am currently doing but 1/3 bigger. It makes fitting the fan in a lot easier.

But don't hold your breath! :lol:
Once Concorde is finished I want to try something much smaller!

The test duct complete.



All I need now is the 70mm Fan to go on the front.
Then we can find out just how inefficient it really is.

Could I ever face making another slightly bigger one?
Not right now!

Quorneng wrote: ...........Could I ever face making another slightly bigger one?
Not right now!

So, it looks like the size of this one (that you're not building, of course) has been fixed already, then.

I'm not waiting for the test flight, then!

IF I was going to build the complete plane by making it a bit bigger the bottom of the fan would be flush with the underside of the duct and not intrude into what is the nose wheel fairing. It would make the front end of the duct rather simpler to make.
It would also mean a true scale intake would be just over the FSA rather than slightly less.

So far the biggest issue I can see is the CofG.
The fan is so far forward that I expect the battery would have to be mounted behind it and the fuselage is pretty small at that point. I am not sure there would be enough room! :ohmy:
However with the larger overall size it may be possible to move the fan back far enough to require the battery to be in the bigger part of fuselage.

Enough of this I must get back to the Concorde.

The 70mm fan just resting in position on the duct.

Looks exactly the same as the 40mm fans I have in my Concorde only bigger and phew! it is screwed together not glued!
Quite a beast showing 44A (439W) at 9.8V on my watt meter from a 3000mAh 3s.
This is strange as the HK web site says this EDF only draws 18A at 10V! :woohoo: and only 38A at 14.8V. :woohoo: :woohoo: but it is referring to the fan with a 3300kV motor.
The AEO web site shows two versions of this fan and states the 3900kV version (like mine) still only draws 30A at 10V. :woohoo:

This example does show the dangers of relying on manufacturers specs.
It would appear to give some safe 'head room' to couple this EDF up to a 40A ESC when using a 3S, but the watt meter figures suggest you would likely blow it, particularly if the ESC had the typical over rating claimed by many manufacturers.
Fortunately I was using my spare 60A ESC but it still got quite warm after just a few seconds at full power.

Whilst waiting for the
a replacement 40mm EDF for the Concorde I have mounted the 70mm fan on the front of the duct.
Fixing the battery onto the duct with duct tape (like you would!) along with some metal strips.

It pushed the total weight up to 27oz (765g) and it just tries to lift from my hands!

So far it is looking good.

is this for the model you are not building.

Yes it is for the model I am not building but it is helping to convince me to build another one! :woohoo: eventually.