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Cessna O-2


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I have considered the issue of cockpit glazing for a couple of days.

As this is a really light weight plane I have come down on the side of 'solid' with painted on glazing as this means the entire canopy can be made of the same 3mm Depron as the rest of the airframe.

Yet more planking!

Canopy start

The canopy will end up as a complete box so light and rigid. It will be held down with magnets.

If I don't like the effect the underlying structure will allow full glazing to be added.

Edited By Simon Chaddock on 17/05/2013 23:59:04

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The canopy complete and painted black.

Canopy complete

The canopy is basically a light (1/2oz) Depron box.

Canopy off

Its shape means it only needs a small magnet on the leading edge to hold it down.

The next task is to work out how ad what colour to paint the 'glass', probably a silver/grey would look good with such a overall dark colour scheme.

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I'm going to get the Black Horse Cessna 337 at Inwoods next month. Got 2x 80 Four strokes and would be ideal for it. A twin that's not quite a twin. Also a good size to make a preseance.

I've got the ST Models Cessna 337. Flies well, but marginal power on it's two bell motors - don't think it would fly on one.

Edited By Paul Marsh on 19/05/2013 08:21:26

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By what seemed like a miracle at 9:15 pm yesterday evening the wind died right down so 'heart in mouth' it flies. smile

Rather too dark for any video and only a short flight but it does indeed easily go vertical with both at full power and it climbs quite well on one.

It even glides passably well even though the props were wind milling as the brakes on the ESCs are not set - yet!

Video will follow once the weather calms down but in the meantime I have no excuse not to finish the painting. wink 2

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The single colour 'star and bar' is proving to be a bit tricky.

It appears to have been stencilled. This is the only view I have.

StarClose.jpg

I have no idea if it will work but I decided to make a suitable stencil.

First a large scale diagram.

Star print

Then reduced to the right size and the correct bits carefully cut out,

Wing star stencil

Rather fiddly to do even at this size. The fuselage one wil be quite a bit smaller! smile o

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fiddly is right but I reckon its well within in your ability . hope you don't mind me pointing this out but would hate you to realise later or maybe it's intentional but the [ ] brackets at the ends of the stencil have a cut through on the plane image and not on your stencil

Martin

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I first tried using the stencil conventionally with red emulsion and stiff brush but I was not entirely happy with the result especially as any correction would be virtually impossible when painted directly on to the black paint on the plane.

A better result was achieved by creating a 'decal' with spray enamel on sticky backed plastic.

Top (and the plastic surface allowed the paint to be scratched away to create a dummy stencil end link! wink 2)

Star & bar top

Under

Star & bar under

The downside is both the paint and plastic have a much higher gloss finish than the rest of the plane but I will live with it for now.

Made a start on the windows, pale grey looked best, using a paper cut out as a guide.

LH Windows.

The low down windows are only on the other (pilots) side.

And I have still have to make that smaller stencil for the fuselage stars! sad

Edited By Simon Chaddock on 24/05/2013 10:33:42

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brilliant stuff Simon,still can't believe it's depron.. Inspired by your use of depron I'm building a Diamond DA42 out of packaging polystyrene ( I had a load of it packed around a new bed) its fragile stuff but laminated it is pretty strong and a learning curve on finishing and carving ,all good fun except the mess

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yes I like the look of it,some of these new composite light aircraft are a mile away from the aircraft of the last 30 or 40yrs there is also one called a panthera made by pipistrel in Slovenia.

anyway if you wish have a look here link to see progress so far..this poly model will help me identify potential weak areas before building one out of balsa

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It was lovely this morning so here's a video of what is only its second flight.

Nothing too dramatic as it is still without its wing struts.
The complete lack of motor torque is very reassuring.
I have edited out most of the bits where it is gliding but for a scale power plane it does a pretty good impression of a power glider!
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Really nice this morning so the Cessna was out again, this time with the ESC brakes set on.

I did video all the flight (18 minutes!) but this is the bit with just one motor. It is still reasonably aerobatic. The roll rate is rather low.

I landed after 7:30 simply for practise - not a good landing.
Flew again without recharging the battery and wafted gently about (first with both then on one) for a further 10:30.
The second landing was much better.
It really loiters at remarkably low power and seems to use less power with one which suggest the drag of the stationary prop is more than countered by the saving of running one motor.
It glides quite well too with a 'power to glide' time of about 1:12 (5s full power gives 60s glide)
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As it seems to be able to fly on so little power and it was flat calm this morning (and a bit of drizzle as well!) I went out for a 'loiter' flight using just one motor and with my HK Altimeter on board.

28may13 long flight

I continued to gently climb to check how visible it was at height. Against a complete overcast the all black actually stands out very well. I could have got quite a bit higher but the cloud base looked very low and I didn't want to loose it just yet!

It was not at the LVC but the drizzle had turned to light rain and the DX6i and I were getting rather wet so i called a halt.

Still just short of 29 minutes is not too bad.

Of course the stationary front prop just created drag. Now if it was a folder......wink 2

Edited By Simon Chaddock on 28/05/2013 21:32:22

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Stephen

At the moment only the front motor can be switched off from the Tx.

I chose this way so the front prop could be stationary for landing. The rear prop is higher and so is almost fully protected by the fuselage.

It is normally launched with both running but it has been launched with the rear only.

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Having been blown about yesterday at the Bury scale fly-in yesterday of course today the weather this morning was perfect, blue sky, warm and virtually no wind so my Cessna went for a maximum duration flight.

03 Jun 13 long flight


I did video it all but it would only make a good entry for the most boring video of the year! wink 2

This edited version shows the launch and landing. The key fob cam on screen clock shows a flight time of 44:45. smile d

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The Cessna really does has the most benign handling allowing 'low and slow' positions that could spell disaster in almost anything else I own. Of course its extreme thrust to weight helps as well.wink 2

An edited video of some spirited flying.

The whole flight was along similar lines and lasted nearly 20 minutes.
This type of performance would be nothing unusual for a lightweight foamy but it is not quite what might be expected from a scale twin!

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