Simon C's Depron Ballerina

[Simon Chaddock]

I will put this here because it is (or was) a Peter Miller Ballerina but made of Depron right at the end of the 2016 mass build.

Although built to the free plane outline it was unusual, apart from being ridiculously light, in that it had retractable U/C including the tail wheel.

After hanging on the wall for nearly 2 years I decided to fly it only to discover the retracts had failed. One leg simply did not move and the other went up and down a couple of times and then failed extended.

Obviously with 'one up & one down' it could not be flown.

To make matter worse I fly from a rather rough grass field so most of its flights were hand launch and belly land with the U/C just retracted for show!

The retracts were cheap HK units and even if I wanted to replace them they are no longer available so I made the decision to make it hand launch and belly land only!

This would also save a bit of weight, not that an all Depron Ballerina really needs it.

Some 'surgery'.

The ribs ahead of the spar replaced with 'printed' ones.

Hopefully when the skin (2 mm Depron!) goes on you won't be able to see the join.

[Simon Chaddock]

The skin replaced.

The top surface.

The under side.

The next task is to 'make up' the fuselage to account for the loss of the wheel wells that stuck out ahead of the wing.

Originally it had an early Lemon gyro receiver than only provided stab on one aileron channel so they had to be on a Y lead. Now the stab rx has gone 'dual ail' can be used with tx programmable differential. 

[Peter Miller]

My Ballerina is still flying in someone else's hands and they love it. They are also loving my Peggy Sue 2 and learning a lot with it.

[Graham Davies 3]

3 hours ago, Peter Miller said:

My Ballerina is still flying in someone else's hands and they love it. They are also loving my Peggy Sue 2 and learning a lot with it.

That'll be me!

 

I love both of these fantastic models. They fly so well, they are default options and the ones that I use to 'learn to fly'. By that, I mean I practice specific things. Between these two models, I am closing in on 150 flights now!

 

Graham

[Simon Chaddock]

This shows the fuselage and wing mount that has to be made up to replace the wheel wells.

One advantage of what is basically an 'all skin' construction is that if you cut out the old skin and put in new the weight addition is just that of a few sq cm of foam and is just as strong and rigid as the original.?

[Simon Chaddock]

The completed "Hand launch/belly land" Ballerina.

It weighs 19.4 oz (550g) with the same 1800 mAh 3s it used before giving a saving of 74g or 12%.

The CofG is virtually unchanged. The loss of the retracts and mains ahead of the spar exactly matches the removal of the tiny tail wheel retract mechanism.

Its wing loading of 5.3 oz/sqft is well within glider territory. ?

Just need some properly calm weather to try it.

 

Edited April 7, 2022 by Simon Chaddock

[Simon Chaddock]

Not that is very significant to the story but the 'no UC' Ballerina suffered a bit of a mishap.

About 2 seconds after a perfect maiden hand launch everything went dead, no motor, no control. It was climbing at the time so it stalled and dived at about 40 degrees straight into the ground.

Just to annoy although all the electrics had been dislodged everything still worked but the rx LED was flashing indicating it had suffered a loss of signal 

Apart from the removal of the retracts nothing else had changed except I had bound the receiver to a HK TX6i Tx rather than the Spektrum DX6i that had been used on the previous flights. This raises a question as to whether the HK version of DSMX is as 'robust' as the Spektrum version.

Anyway with no flying due to the  strong easterly wind took the opportunity to do a  complete nose rebuild, this time using 5mm XPS rather than 3mm Depron so it now looks like this with a new prop.

Just the battery hatch still to do.

The suspect rx has been replaced by a Lemon 6 ch with diversity antenna.

Just in case I will also set the elevator failsafe position to be just a touch up. ? 

 

 

Edited April 25, 2022 by Simon Chaddock

[john davidson 1]

I had problems with Orange rx's , would fly  ok then even almost overhead, loss of control. Changing to another rx would eventually have the same problem, even thought it was the tranny. Now use the antennaless Spectrum 

[Simon Chaddock]

Just to confirm it was not the rx but the HK TX6i. 

On the Lemon rx it did exactly the same thing, after about 4 or 5 seconds the signal was lost. After another couple of seconds it would reappear only to go round the cycle repeatably. It would do this at any range. No damage as the Ballerina was still on the ground.

Rebound to a Spektrum DX6i and it all worked perfectly allowing the now 'super light' (it never was heavy!) Depron Ballerina to float about for 10 minutes.