So what about a Gloster Javelin then ......

[Spitfire]

Thought you might all like to see my mate with the golden fingers new scratch build - a twin electric ducted fan Javelin



Completely own design - all hand drawn plan - fully to scale .....

I'll post the photos as he sends them to me...... I love to see his builds develop ......

so here we go ....

Very delicate...


Great precision ....






Motor tube is rolled 1/32nd balsa
Look how accurately that tube runs through those formers


Motor and speed controller mounted in one side already - tested and apparently very satisfactory 'Thrutch!'

[RLN]

That is nice! Keep the pics coming as soon as you get them

[Xplumberlives]

Wow, a wooden exhaust pipe!

[Mayfly]

Brilliant SF thanks please keep us up to date!!!

[Gaz]

One of my faves! Looking forward to seeing this progress

[MrTim]

Here's XH767 at Elvington today:-

[Jigsaw]

Excellent thread SF. Keep updating as soon as you can mate. Good stuff

[Spitfire]

Well he's finally sent me some more pics... bleating about being busy or something

The ducts are a 'build thread' all by themselves being precisely tapered and rolled from soft 1/32 balsa (supported from the outside by the fuselage frames).

Soft 1/32nd balsa .... nightmare But he makes it look SSssssssooooooo easy

[RLN]

Very nice, SF. It would have been kindling by now if it were me.

[Nickolas]

I quite fancy doing a 'scratch' build.
I have been trawling the web for suppliers of 'scratch' but can't find any.

Any (polite) advice anyone??

It appears that 'scratch is not only very versatile and it's edible too but seems to be in very short supply.

[Stigish]

Blimey, he must be one patient bloke spitters! I'd have given up at drawing stage. Keep the pics coming.

[Spitfire]

Blimey, he must be one patient bloke spitters! I'd have given up at drawing stage. Keep the pics coming.

Things just seem to 'happen' when he picks stuff up .... you give him a cylinder and a piece of balsa wood that you want a relevant hole in and he'll cut that hole with a knife - freehand and by eye only - and you can bet your bottom dollar the cylinder will be a perfect engineers fit all around - invariably first time of asking

[Dougs]

better keep an eye on the jet pipe temp fantastic work!!!

[Gaz]

Wow! You should organise a forum outing for its first flight

[Mayfly]

excellent - oh what patience!!!

[Spitfire]

It's moved on a bit .....



He was on the phone tonight and gave me the benefit of the sound of both motors running full thrutch down the phone - this is because he wanted to impress with the noise .....they are both 3 bladed 32mm ducted fans and they run at 5500 revs per volt and they're running on an 11.1 volt battery (61,050 revs each ) - at full thrutch drawing 14 amps (I never understood that bit but you technical people might - all I need to know is it works ok )

Boy do they scream - and he says they create a LOT of wind down those ducts and it will be AMPLY powered.

What you can see in the photo is the radio receiver at the back - with the thin black aerial lead - on the left and right are the two speed controllers that make the motors throttleable - these are all roughtly connected at the moment to test the motors - all will be neatly connected and stuffed away in the hole you can see which will be under what will be the cockpit.

He'll probably be ready to test fly it pretty soon - unpainted - then when any glitches are resolved add the pretty bits

[Cluny]

[Mayfly]

Brilliant SF

What is the wing span? or have I missed that somewhere?

[Xplumberlives]

Brilliant SF

What is the wing span? or have I missed that somewhere?

Not quite big enough for you or S.M. to fly!

[Mayfly]

[Spitfire]

Brilliant SF

What is the wing span? or have I missed that somewhere?

Nope - no dimensions given - I'll ask for interests sake

[Lucas1860]

Great report, bring it on with more updates.

[Xplumberlives]

What is the wing span? or have I missed that somewhere?

At a rough guess I would sumize that it's about 21 inches long and has a 19 inch wingspan!

[Spitfire]

Not far off ..

You wanted dimensions - well here you go - direct quote

I either hadn't measured or not recorded the desired data - thanks for provoking me to do it. They don't fly because of the numbers, they fly due to principles such as being 'light enough', 'enough thrutch', 'big enough' etc. etc....
However:

To be modelled on the one hanging in Cosford -


Scale - 1:24 (1/2 in. to the foot)
Construction material - proper balsa and a 'smidgin' of 1/64th ply
Span - 664mm (26.1 in) ie. 'quite small'
Length - 715mm (28.2in)
Weight - 360g (12.7oz) inc. 1100mAH lipo battery (as seen in last photo)
335g (11.9oz) inc. 850mAH lipo
EDF units (2) Derek Knight 32mm
Motors Feigao 12mm brushless inrunner (7500 kV)
Static thrust (measured) - 165g (6oz)
Power input (max.) - 14A @ 11.0V ie. 154W

Rx - Spectrum AR6100
Speed controllers (2) - Robotbirds Pro - 10A
Servos - Supertec Pico 5.4g (3)

I could work out wing area/wing loading if anyone is bothered but it won't make it fly any better or make it less likely to crash!

Enough detail ??

[Gaz]

I'm still holding out for an invite to the first flight