Ballerina by EarlyBird

[john stones 1 - Moderator]

4 minutes ago, EarlyBird said:

Normal service has been resumed, I am pleased to say. ?

 

I removed the washers adding the up thrust. Removed some lead to reduce the 'nose heavy'. I am now back where I started and, all I need to do is fly it and get used to it's flight characteristics.

 

I don't think there was ever anything wrong. ?

 

Cheers

 

Problem is mostly the person holding the Tx Steve, we've all been there, done that. ?

[Geoff S]

On 08/04/2021 at 11:49, kc said:

My rule is to not change anything until I have found the cause of the fault.   Once you start changing things the evidence is gone!

 

A significant part of my professional life was involved in fault finding (almost all with electrical/electronic equipment or software) and the most common method was replacement of components.  The important thing is to do it logically and as far as possible change one thing at a time.  It works, as I demonstrated only last month when I successfully repaired our micro-wave oven.  It was the 3rd component I replaced that did the trick - the first 2 were cheap and easy to replace, the third, the magnetron, was both more expensive and more difficult.

 

 

[Trevor]

But surely Geoff, after all those years of experience, you would have known that Sod's Law dictates that it will be the most expensive and difficult-to-replace component that has failed? ?

[EarlyBird]

After thinking about the up trim on the elevator.

 

 

I thought investigation was required so I searched for "RC plane nose heavy" on the internet and found a video in which the plane flew exactly the same, before I removed some lead. There was also one where the model tip stalled on landing approach.

 

These are examples of way too nose heavy as they were very difficult to control. My conclusion is that my Ballerina was way too nose heavy. Yes too nose heavy can end in disaster and I was lucky to get away with it.

 

In comparison I started with a Riot,  I had bashed it about and during flying I lost the nose weight and did not realise until later. Maybe this made me a bit lax about the CG position but I have recently found out that Riots are insensitive to CG position and obviously this doesn't apply to all models.

 

Something else I learned from the internet search is that flying the model is the way to refine the CG position to ones liking. 

 

The up trim could indicate slightly nose heavy so move the battery back slightly and test fly is my current thinking.

 

Interestingly this is exactly what I did with my HK Crusader the ultimate test being inverted flying, nose heavy meant loads of down elevator was required. But the Crusader cost £85 and took a couple of hours to build and was well used before I started trying to fly inverted. Whereas the Ballerina took me months to build, the cost is irrelevant, and I am reluctant to take liberties with it.?

 

Interesting and more fun to come, this is why I build and fly RC. ?

 

Cheers

 

 

 

[Geoff S]

There is a huge difference between a foamie that took about an hour to assemble and a plan (or kit) built model on which you've lavished many, many hours over several months.  A club mate remarked on the slightly uneven flight of my DB Gypsy Moth on only its second flight and I pointed out that the model was fine, the uneven flight was because I was trembling ?

 

It gets better.  After numerous flights I now throw the Gypsy around enthusiastically.  I'd be very sorry to see its demise but the anxiety has greatly diminished.  The next thing to worry about will be the maidens of my Li'l Cub and, even more, my Sopwith Pup!  As a very experienced model designer, builder and pilot once remarked to me "It's a hard game sometimes."   I dropped out for a whole year recently for that very reason.

 

Hope you get the Ballerina sorted.  I think your approach is the right one.  btw the Riot isn't particularly CoG insensitive in my experience.  With the steel nose weight removed it's much more aerobatic but still quite easy to fly.

[kc]

Is that rudder clevis fully clipped in?

[EarlyBird]

20 minutes ago, kc said:

Is that rudder clevis fully clipped in?

Well spotted and it is now thanks.

[EarlyBird]

I spotted that when I was adjusting the elevator control horn position.

 

During the last flight the elevator was very sensitive, tail heavy? was my thinking, but when I landed I realised I was on high rates, not very SMART. In the workshop I was checking the throws against Peter's recommendations( low 1/2 high 3/4) I use a three position switch for low, medium and high. My throws were 1/2, 3/4 and 1 ? no wonder it was sensitive to the elevator ? but it did add to the fun with tight loops. 

 

Cheers

 

 

[Peter Miller]

Getting it sorted I see.

[EarlyBird]

On 11/04/2021 at 13:18, Peter Miller said:

Getting it sorted I see.

Yes Peter and I gave her the fifth flight with her today.

 

I gradually moved the battery back and now there is a very slight up trim on the elevator. I think I can move the CG further back as the elevator on low rates didn't feel at all over sensitive. Then I have to pluck up the courage to check by flying inverted. ?

 

I am enjoying flying my Ballerina.

 

Thank you Peter.

 

Cheers

[Peter Miller]

Glad to hear that your are getting to grips with Ballerina.

I am sure that once you have her sorted out you will love her

[EarlyBird]

It was love at first sight and that was before I started the build.

 

Another flight gradually moving the CG back. I now have it where I like it to be. ?  She goes where I point her and opening the throttle makes her speed up along the same line. I tried infinite vertical looked promising until she veered left with a gentle spin at the same time. Next job is to trim the rudder.  It's all part of the process and part of the fun. I am using 4000 4S which will give over 10 min flights so I have been practising flying while sitting down, no problem.

 

I also proved that Ballerinas are tough with a few less than perfect landings in the 10MPH cross winds. You did say Ballerinas were tough Peter. No damage to report apart from a couple of grass stains.

 

More fun tomorrow. I could take more than one battery ? Interesting how anxiety decreases and enthusiasm increases with every flight. 

 

Cheers

[john stones 1 - Moderator]

7 minutes ago, EarlyBird said:

It was love at first sight and that was before I started the build.

 

Another flight gradually moving the CG back. I now have it where I like it to be. ?  She goes where I point her and opening the throttle makes her speed up along the same line. I tried infinite vertical looked promising until she veered left with a gentle spin at the same time. Next job is to trim the rudder.  It's all part of the process and part of the fun. I am using 4000 4S which will give over 10 min flights so I have been practising flying while sitting down, no problem.

 

I also proved that Ballerinas are tough with a few less than perfect landings in the 10MPH cross winds. You did say Ballerinas were tough Peter. No damage to report apart from a couple of grass stains.

 

More fun tomorrow. I could take more than one battery ? Interesting how anxiety decreases and enthusiasm increases with every flight. 

 

Cheers

 

Man after my own heart, plenty C.Gs on a model, find one you like by tweaking. ?

[Peter Miller]

I am glad to hear that you are happy with her.

 

You have joined a long list of Ballerina fans.

[Geoff S]

I haven't flown mine for ages (probably seems longer with last year's lockdowns).  I think I'll take it up to the new site next time I go - either tomorrow or Friday.  It's getting to the point that I'm one of very few club members flying models we've built either from plans, own design or kits. 

[Peter Miller]

9 hours ago, Geoff S said:

I haven't flown mine for ages (probably seems longer with last year's lockdowns).  I think I'll take it up to the new site next time I go - either tomorrow or Friday.  It's getting to the point that I'm one of very few club members flying models we've built either from plans, own design or kits. 

There are only three of us in our club at the moment who build plus one of who is very very occasional.

 

One other used to be a keen builder but not now.

[EarlyBird]

Windy today so to the field with my pride and joy Ballerina.

 

What a pleasure to fly in a wind 'wind what wind It's only 12 mph' she said to me. 

Now I am wondering what is too much wind for her.

It just gets better and better.

?

[Peter Miller]

Glad that you had some good flying today

[EarlyBird]

Thanks Peter,

 

As my confidence returns I will start some mild aerobatics and 'B' manoeuvres. 

You have said Ballerinas are tough and I have put this to the test and can confirm they are very tough. I have found it impossible to bend the undercarriage for example.

 

A club mate commented on how well she flies. Yes like a low wing trainer on low rates but I have yet to try full rate aerobatics, intentionally ?

 

I foresee many more good flying days to come with my pride and joy. 

[Peter Miller]

Well I liked her and so did all the people who built her for the mass build and now I keep getting rave comments from Graham 3 so I must have got it right.

 

I am currently building a cross between The Ohmen and Ballerina  to be called "Hound Dog"

[EarlyBird]

7 minutes ago, Peter Miller said:

I keep getting rave comments from Graham 3 so I must have got it right.

There is no doubt as far as I am concerned Peter. The Ohmen is my next build which means I will just have to build your upcoming "Hound Dog".?

[Graham Davies 3]

2 hours ago, Peter Miller said:

Well I liked her and so did all the people who built her for the mass build and now I keep getting rave comments from Graham 3 so I must have got it right.

 

I am currently building a cross between The Ohmen and Ballerina  to be called "Hound Dog"

I do indeed rave! It's a great 'go-to' model and certainly is good in 15mph wind as that's as far as my research goes!

[Peter Miller]

2 hours ago, EarlyBird said:

There is no doubt as far as I am concerned Peter. The Ohmen is my next build which means I will just have to build your upcoming "Hound Dog".?

I willbe starting a build blog soon for "Hound Dog"

[EarlyBird]

More flights in the last couple of days. ? I am becoming more comfortable with her, this has enabled me to fly faster without fear. The elevator is now trimmed neutral and she flies where I point her, increasing throttle has no effect apart from increasing the speed. I have experimented with CofG and elevator rates which is a work in progress but I am getting close to how I like my models to fly. Obviously more fine tuning to come which is all part of the fun.

[Steve Goodwin]

On 31/08/2020 at 11:26, EarlyBird said:

Interesting so it's just a case of having the correct technique and iron temperature. I must give it a go.

Meanwhile wing dowel and ply plate are gluing.

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Cheers

Steve

Enjoyed this build blog very much @EarlyBird and your model looks solid and really well built. As you may know I'm building Ballerina as my first build too and have noticed that I have done something quite different to you ?. I epoxied the supplied ply wing fixing plate to the fuselage, you have used the ply plate on the outer skin of the wing. Your wing fixing blind nuts are installed in what appears to be balsa, have I got it the wrong way around?