A Depron plane destroyed or is it?!

[Simon Chaddock]

A few years back there was a Peter Miller Ballerina mass build.

Just because I chose  to build a 3/4 size one out of 2 & 3 mm Depron with just a touch of balsa for the spar flanges.

Not quite faithful to the original plans but it did fly very well being ridiculously light.

As it was smaller I named it the Petiterina.

After a couple of years flying it was modified to have a exposed printed scale 9 cylinder radial in a shorter nose.

Giving it an 'agricultural' look.

Still going strong after 2 more years until 2 days ago when after a 15 minute flight for some reason all control was lost. It spiralled in from about 50 feet.

The motor with the dummy radial pulled out the ESC bullet connectors as did the battery from the Deans. The wing is broken in two and the tail dislodged.

With such a complete loss of control and power I assumed perhaps the ESC had failed so I simply plugged everything back together where it lay and it all worked!

After 5 years use, not a bad life for a lightweight Depron plane, I decided to "retire" the bits but I do so hate to throw anything away particularly when built in 'original' Depron as it is no longer available.

So first restore the dummy radial. Apart from gluing back several cylinders It also needed two cylinder heads and several push rods but easy to do as I have all the print files.

Restoring the rear fuselage and tail plane is also easy but the rest of the fuselage will have to be new.

I do have plenty of 5 mm grey soft EPS foam used under laminate flooring. Much more flexible than original 3 mm Depron but no heavier.

So the original rear end grafted on to a new front.

It follows the original fairly closely so the undercarriage and the battery hatch can be reused.

The wing will be more of an issue as I don't have the Depron to restore the badly damaged right wing root. The grey 5mm EPS is just too flexible in such a high stress position so I fear the only solution will be to "loose" about 3" of the right wing, re-join it and accept that the dihedral break will off set 1.5" from the centre of the fuselage. ?

Not concerned about the reduction in wing area as it has plenty of power and its original wing loading was well into the 'slow fly' class.

 

Still work in progress and then I wonder why I have so many models to store!

 

 

   

 

 

 

Edited April 21, 2021 by Simon Chaddock

[Dwain Dibley.]

Excellent Matey. 

I do love a rebuild.

D.D.

[Colin Leighfield]

I remember this one Simon! You’ll certainly have it flying again.

[john davidson 1]

Did I spy an Orange rx in the rubble?

[Simon Chaddock]

John

Well spotted.

An old Orange DSM2 'micro' 6 channel with 'diversity' aerials!

I use an equally old Spektrum DX6i of just the right age that works both DSM2 and DSMX types seamlessly. 

 

[SIMON CRAGG]

Well done. I recently purchased a virtually "destroyed" Dynam FW190 which was on its way to the local dump.

 

Total cost £25.00.

 

After some very enjoyable repairs and upgraded motor etc. it flies beautifully. I have restored many trashed models over the years, and find it very rewarding to say the least!.

[J D 8]

  I rarely build anything new these days, just when I think of doing so some restoration project comes my way. ?

[Simon Chaddock]

Its virtually finished. Just a couple of touch up jobs.

And it all works!

In deference to the rather more flexible foam used in the forward fuselage half the wing is now glued into position rather than held with 3 nylon bolts as previously. Rigidly closing off the fuselage underside adds significantly to both its bending and torsional rigidity.

If anything the slightly reduced span has improved the appearance giving a more compact look, well I would say that wouldn't I! ?

My apologies to Peter Miller for emasculating even further his original Ballerina design. ?

 

It was not just my 'stingy' nature that drove me to restore it but the importance to me of its horn free and closely shrouded aileron system.

 

This was the first time I had attempted to do this in Depron. Not that it would make the slightest difference to the performance of this plane but the technique was used on the Endurance where the aim was to achieve level flight using just 11 W/lb. A plane with aerodynamics where, to miss quote the Tesco slogan, "every little really does help".   

 

 

[Simon Chaddock]

This morning was sunny and calm, again, so to complete the story I can confirm that the rebuilt Petiterina flies and pretty much like it always did.

The reduced span has increase both the roll sensitivity and the roll rate. With the servo arms directly attached to the ailerons it always was pretty sensitive but it is now so sensitive I was finding it hard to fly smoothly so I landed and set 30% expo.

Believe it not this was the first time I had ever set expo on any plane of mine. As about 1/3 of my planes are flying with an old Futaba on 35 meg where any Tx adjustment applies to everything I use the 'old school' method of mechanically adjusting linkage to give the control I want.

The expo certainly smoothed things out quite a bit.

The most important aspect was it flew for 8 minutes, did two landings in that time, yet sustained no damage.

[GrumpyGnome]

Result!

 

I too am not a fan of expo, and rarely use it.

 

GG