Folland Gnat T1

Made a start on painting the Gnat.

The acrylic paint, apart from colour, also stiffens the surface which makes sanding the joints easier. In addition it also 'glues up' any minor gaps between the planks.
The colour scheme will be simple to save weight. Fuselage red, all the flying surfaces white. As they all have one piece top and bottom skins they will only need a 'dusting' of white acrylic to achieve an all over 'titanium' white finish.
I might do the control surfaces blue (patriotic?) as it is fairly easy to do with only a minimum of masking.

I thought the 'Arrows' Gnats had red wings too?
If it's meant to be a regular service Gnat, I thought they were in camo with roundels and the tri-colour bar on the fin..

Ha!
It is red simply because it gives a very 'solid' colour to cover the planking joints, it is easy to see and I already have a big pot of it.
Nothing to do with the Red Arrows. It will not even have RAF markings on it just my CAA number on one side of the fin.

As far as I'm aware the caa number can change when you renew?
I've simply placed my details on a label under the centre section of the wing on the models that need it, easy enough to peel off if needed..

The CAA regs say to be legal a current number must be displayed on a rigid part of the air frame but not that an old number has to be removed.
As a lightweight foamy I am sure it will be retired crashed well before I run out of space on the fin.

What number ?:evil: [badass]

Tony, thanks for the warning, but if I could have got proper enamel and not the weird smelling stuff they flogged me I would put it in my spray gun. No propellant, but good air. In the end I gave up looking and used a tinlet of Humbrol silver and detailed it a bit with a pencil, then used a very thick mix of emulsion that B&Q made up for my Cub model on the zinc chromate bits. Spent today remaking the elevator and rudder which the emulsion silver ruined by having to be too wet to spray. Painted the starboard side of the fuselage. Now just the panel line details and then it'll be glue the wing on.
Cheers,
Martin

It is nearly finished.

Simple paint scheme no fancy detail. The wings still need a light coat of white and magnets to hold down the canopy.
Couldn't be bothered to wait any longer for the servo reverser so I cut out the LH servo and turned it round 180 degrees.

It is now orientated the same way as the RH one and I tested them to make sure.

The Gnat is now complete.

Its stab rx was 'liberated' from the Ballerina and suitably adjusted to match the Gnat's servo directions.
Without the battery it weighs 338 g (12 oz) so comes in at 447 g (15.75 oz) with its 1500 mAh 3s. A bit heavier than I expected but should still fly ok.
It really needs a more efficient rather than a more powerful EDF.

That looks very good, a very clever man, respect

As the weather was still passably calm I decided to maiden the Gnat today.
It flies but ooh! eer!
Thrust plenty but the first attempt ended in less than 10 seconds hitting a small tree. No obvious aileron control to the right.
The damage.
The cockpit canopy sprung open and remained in the tree.
The reason.

A compression "shake" to use the timber term and its the same on the other side the result of a sudden upward blow on the nose?

The LH wing hit a branch and 'dinged' the leading edge.

Gently squeeze the wing damage into shape and used the canopy to force the cockpit area back into shape and try again knowing lots of RH stick would be needed.
It actually flies pretty well but it needed both full RH trim and a bit of RH stick to fly straight so just gentle circles. Even flew it with the gyro off but the handling felt rather unpredictable. With the gyro back on after 4 minutes an easy into wind gentle landing.
So what is wrong?
A picture tells a thousand words. :ohmy:

A serious warp to cause a LH roll. :woohoo:
No wonder it needed so much RH input to fly straight in fact with its small scale ailerons it is amazing it could be controlled at all.
Of course I should have spotted this. It is amazing how good the Mk1 eyeball is at spotting defects - once you know what to look for! :dry:
At least it flies so on with putting it all right.

I see your problem. :huh: I would be interested to know how you straighten that.

crash
In the southern part of the US Depron is not favoured as it softens and distorts readily if in a car in strong sunshine.
Not much of a problem in the UK so heat and manipulation is the answer to curing warps in a Depron sheet covered structure.

Heat gun on the floor, press the trigger with your foot, to leave both hands to hold the offending section in the desired position in the hot air stream. The fact your hands are in it as well ensures the temperature keeps under the Depron actual 'softening' limits.:ohmy:
Maybe not perfect but much better than it was.

And the leading edge repaired and the paint touched up.
Fuselage repair in progress.

Just to complete the picture the fuselage is now fully restored.

The nose also needed some minor internal repairs as part of the battery box had come loose from the impact of hitting the branch.
Now just need the weather - some hope - showers and gales forecast!

Oh dear!

And I was wondering what to do next.
1st error
The weather looked good and not too windy (at times). I should believed the weather forecast and not been deceived by the sunshine and mild conditions.
2nd error
I forgot to switch on the gyro.
As I launched at full power a sudden gust, but at almost 90 degrees to the direction of launch, resulted in a severe roll to the left. Just managed to catch the roll but not the descent into the ground still at full power and at quite a shallow angle. The ground is very soft and pitted from dog walkers foot prints so there was little chance of any sort of slide just a dead stop. The nose block ended up buried 2".

As usual with these Depron structures it seriously crumpled so it looks 'terminal' but crumpling absorbs energy so the rest of the structure is completely undamaged and everything still works.

All it needs is a new fuselage from just ahead of the intakes. Simples!
At this rate this blog could go on for some time.