the box kite

[riverlandgirl.]

Hi All.

Here is my latest experimental.

I'm trying to see just how slow a slow flyer I can come up with! Due to the limitations of my building methods, I have so far been unable to build a small electric with a wing loading under 2oz (all though my seal pup comes close). I thought I would instead try a very high aspect wing and wrap it around to keep the model a managable size! This works out at 60" span with a 3" cord. weight 17oz, static thrust of 7oz. For a comparison, I used this model as my trial horse.

60" inch by 6" wing, so same wing area. static thrust is the same, but weight is 14 oz. The new one flies well and can fly slower on a higher wing loading at the same power. (It is also is less inclined to tip stall)

Rudder/ele/thr.

Quite happy with it I think, even if it's somewhat ungainly!

regards Lynn

[WolstonFlyer]

Hi Lynn, that looks great! Congratulations on another super self design model The photo with the orange sky is wonderful.

[John F]

Lynn, I like it.  How did you build it?  Is it foam wing?

I agree the orange sunset looks superb with the model.

Tri-Plane next?

 

Edited By John F on 22/03/2014 08:54:14

[Stephen Jones]

Hi Lynn ,

Looks great .

And i think that the top picture is the best ( dscf5677 ) one for the photo Album ,me thinks

,

[Simon Chaddock]

RLG

Very interesting and beautiful 'atmospheric' pictures!

I think you neatly discovered the drawback of a closely spaced biplane wing. A lower wing loading does not automatically mean a lower stall speed.

I suspect if you had built in more stagger (and possible more decalage as well) to the wings and maintained it at a constant value all the way, the wing tips would almost become a 'slotted flap' and maybe less likely to stall at all.

[riverlandgirl.]

Thanks for the comments.

It was a bit of a battle to persuede my partner to take the photos, but it was worth the effort!

John, The plane is all polystyrene, with tape covering, and a minimum of timber spars.

Simon. You are quite right, there is no stagger to the wings, and the incidence is the same upper and lower. It would be quite interesting to play with leading edge slats..

The other thing that I have been experimenting with, in my last few models (seal pup {front lawn 'leckie} LBS,) is using an under cambered tail plane and motor up thrust, in order to gain more lift. The result is as you open the throttle, you feed in down elevator, and the model climbs very quickly in a level attitude. C of g is at the normal location.

This model has a geared 380 can, and a 11 x 4.7 prop on a 1300mah 3s. She has surplus power, so I may try her on a 2s 500mah, which would knock a couple of onces off. I've only had the one flight so far, rather breezy at the moment, but look forward to putting her through her paces.

thanks.

Lynn

[riverlandgirl.]

Well, I can't complain about today's weather. One of those rare perfect flying days, flat calm! Yay. Had four flying sessions with four different planes. (No, I didn't keep breaking them!)

Put the box kite through her paces, this time on the two cell. Perfectly adequate! The GWS web site gives my combination of motor/gearbox/prop 6oz static thrust (I measured 5oz) on two cells. The weight came down to just under 16oz ( I have to make a plug adapter, to use the 500mah, so I used a 1300 2s instead) The climb was good, and she would cruise around happily at a little over half throttle. Not too bad at all!

[Bob Cotsford]

You really do like 'different' don't you Lynn? At 16oz you'll have to watch out for thermals trying to whisk it away.

Edited By Bob Cotsford on 23/03/2014 09:34:41

[Mowerman]

Another wierd and wonderfull model, it flies and you obviously have great satisfaction from your unorthodox models.

Well done.

[riverlandgirl.]

Thanks for the comments. I do rather enjoy trying out whims, on a "If you don't try it you'll never know" basis. About 45% of my models fail, but that's ok. ( I should post a thread of my failures one day, could be quite entertaining!)

Thanks again

Lynn

[Chris Bott - Moderator]

I think that's lovely RLG.

How about this for a quick tweak of one of your pics?

[Wiltshire Flyer]

My senses are telling me not to like it..... But my modeling brain says it looks great in the air!
It's the wings that do it... Great job!

[riverlandgirl.]

Thanks Chris, I do like that tweak! (I never think to play around with the photos before I post them)

I agree with you WF, it is a rather mishmash of a thing, not sure I much like the look of it myself, Definatly looks better in the air than on the ground!