Ballance on an electric BOOMERANG 40 question

[Christopher Morris 2]

Hi, got a BOOMERANG 40 that i have converted to an electric. Now all the info i have is for a petrol & it says fit everything & balance with an empty fuel tank. I am assuming with an electric version & the battery is a constant weight & weighing in at 570g/20ozs i should balance with this fitted???. Am i right. Thanks

[J D 8]

Yes, balance with battery fitted and if space allows move batt fore and aft to find the right spot. If you find you still need more weight to get balance correct then do so. [ unlikely with a boomerang I would think ]

[Christopher Morris 2]

Thanks JD.

[Denis Watkins]

Chris, the Boomerang is a dream design that has evolved whereby if you put most of your gear

In the slots and spaces provided, then invariably the model balances without fuss.

You are right about the tank anomally; with IC, we generally go off slightly nose down, and land lighter in weight.

[David Davis]

Fabulous trainer, I use it all the time for instruction. I've had two. I needed the second one after I failed to take back control quickly enough when my trainee became disorientated! Fortunately my beloved Enya 50 was undamaged.

I'd be interested to know how you get on with the electric version Christopher. Which motor, ESC and battery will you be using?

[Christopher Morris 2]

David & Denis, Me too, as i have only started flying this winter & not even flown yet. I have small Bixler foamy to get me started before i try the Boomarang. "as its cheaper to crash" lol
I hope i am getting all ok with my looking around for what has been suggested for the conversion. 1x4250/800kv motor, 80amp ESC with 8amp bec, 5amp 4c/14.8v lipo & a 11x8e prop. I have also made it a tail dragger with large front wheels. Fortunately it has 3 control rod tubes going to the tail & i assume its for ruder, elevator & rear wheel steer, & instead of coming off the ruder for steering, i just put in another servo in & will connect with a Y cable to the ruder.

Edited By Christopher Morris 2 on 15/03/2020 13:14:25

Edited By Christopher Morris 2 on 15/03/2020 13:16:44

[David Parr 1]

Hi, just returned to aero modelling after a break of 30 years, and have been cutting my teeth on a easy glider 4 for last few months. Brilliant kit and great flyer.

However, almost be accident have acquired a Seagull Boomerang ARTF, as order a kit but got a ARTF by mistake! So my regarding weight and balance - this morning I unpacked it and weighted both wings (as I do with all models) and there a different of between 25-30 grams between each wing.

That's a lot, so just asking if anyone would like to comment on this, my fix would be to add needed weight along the length of the light wing. Any better ideas or any general ideas with this model would be most appreciated.

Thanks Dave.

[David Davis]

Assemble the wing. Add small pieces of lead to the wing tip of the lighter wing until it balances. Epoxy to the wing tip.

Alternatively you could always send it back and demand the kit!

[David Parr 1]

Thanks for your reply David - I did offer to return the ARTF model to the shop in exchange for the kit (twice!) And failed to get a reply!! Anyway I'm suck with it now as it been opened and played with !

Yes that's more that likely what I will do is add weight (lead) to the wing tip. In the past I've added weight to the length of the wing by adding piano wire the length of the wing (inside) as don't want tip stalls when flying. But don't you agree 25-30 grams is a lot of different in weight?

Anyone out there made a Boomerang with a two piece wing? I'm looking at doing so to save space at home. By the way I'm a aircraft engineer of over 35 years.

Dave.

[David Davis]

To be honest David I've never weighed wings so I don't know whether 30 grammes is a lot or not. Perhaps I should have done, maybe the models would have flown better!

I am in the process of building a Big Guff, one of the first model aircraft specifically designed for radio control. It first flew in 1938. It's wings are in two parts bolted together in the middle. I'll go and weigh each wing and try to get them to balance.

As for the wing on the Boomerang, I can't remember how they are retained at the front but you could always keep the aluminium tube unglued, as a removable joiner as it were, then drill two holes through the F2 former into the leading edge of each wing. Two short dowels and the job's a good un. The trailing edge will be retained by the bolts as per normal.

[Nigel R]

What does the whole thing weight, 2.5kg?

If so, perhaps 25g is not that much in the grand scheme of things. I'm not sure I would worry too much about weighting the light one, for a cabin trainer design.

[David Parr 1]

David and hello Nigel thank you both for your replies. That's a lovely wing build David, yes that's my thought too on a two piece wing Boomerang wing, and maybe a short flat aluminium (fish plate) across the top of the wings between the two nylon retained bolts too.

Oh one last question if I may David, since you're instructed on Boomerangs? I know there's lots of post elsewhere about this, I fly from a very rough field so what would you recommend trike or tail dragged, thanks again.

Nigel, yes your right a Boomerang is about 2.5kg or a little more. However, if you dry join the wings a 25-30g weight difference makes a big difference and the heavy wing drop readly if you balance them on the centre line. I think far to much to ignore when flying.

thank you both again Dave.