Dragonfly Build Thread

[Ivanhoe]

I've been looking around for a new project, and was sent this plan by a friend in the US.



It's a model from 1974, published in Model Builder magazine, called the Dragonfly and, as you can see, is VERY different!
The design was based on the old "Stick" rubber powered models, the aim was to produce a model which could fly at a VERY low speed, be completely stable, and ideal as both a trainer and fun flyer. The original model was powered by an OK Cub .049, this would not be unusual were it not for the fact that the model's wingspan is 72" yes, 6 feet!
It would do ground takeoffs on the Cub with rudder-only control, but later versions had a variety of engines culminating in the OS Max 10.
The version shown on the plan is the OS version, with three function control, it is reputed to climb like a lift on the OS, but throttled-back was capable of stable, controllable flight at 5 mph.




It's not the prettiest model I've ever seen, but I think it's my kind of model, especially for my proposed aerial video project

[Ivanhoe]

Well, it's a start! Smallest piece first, this is a BIG model!

Next stage is the fuselage, which is 48" long and has 1/16" ply skinning, meaning that I have had to splice the sides, since I do not have 48" long ply sheets.

More photos as build progresses.

[Godsey3.0]

What engine do you think you will use? I actually like the way it looks. I love the big wing.

Rolla

[RknRusty]

If I were to try learning RC, I think I'd like to try one of those types first. I'd certainly write my contact info on it.

[Ivanhoe]

What engine do you think you will use? I actually like the way it looks. I love the big wing.

Rolla

Another reason for building it, I have an OS Max 10 R/C doing nothing at the moment!

I do intend to actually try flying it with a Babe Bee at some point, just to see if an .049 can sensibly fly something this big!

Yes, it's one of those models that is so ugly it's attractive!

[Godsey3.0]

Well, the Gentle Lady has a wing around that size. It can take a pod or an engine on the nose. The instructions show a Bee type engine on the nose and a Tee Dee on the pod.

Rolla

[andrew]

I do intend to actually try flying it with a Babe Bee at some point, just to see if an .049 can sensibly fly something this big!

We have, I think, due to improvements in power/weight ratios and ultra-lightweight radio systems, gotten away from the time when models actually flew and now simply use our planes to steer the engine around.

That being said, here's a candidate for some laid back R/E putzing around. While designed for freeflight competition, this plane could be easily modified by widening the fuselage slightly, dropping the pop-up stab and adding an elevator and moving the fin and rudder to the top side. With a couple of 5g to 9g servos, a 3g Orange RX and NiMH battery pack, you could have a nice floater



Edit: After re-reading the original post, I didn't mean to hijack Wilf's thread. I expect his project will be a real floater and will fly with an .049, albeit slowly as designed.

[Ivanhoe]

Edit: After re-reading the original post, I didn't mean to hijack Wilf's thread. I expect his project will be a real floater and will fly with an .049, albeit slowly as designed.

No problem, Andrew, there are a lot of F/F competition power models flying around with "Radio assist" see the thread on here on the "Timer's Nightmare" for one. Most people use the origional short engine run, then use the R/C to keep the glide within bounds. A lot of 1930s/40s "Vintage" F/F models make superb R/C conversions.

Wilf

[Ivanhoe]

Fuselage is progressing, first time I've ever built a fuselage that is almost entirely 1/16" ply! The 24" ruler will give you an idea just how big this thing is!



Engine & mounting, I had to enlarge the nose area slightly to accomodate the commercial motor mount, the original model had a mount made from bent brass which I did not fancy fabricating.

[mitchg95]

wow looks great Wilf

[Ivanhoe]

A little more progress made, I now have the tail unit almost completed



I still have to hinge the elevators, they are the two-piece, joined-with-a-piece-of-wire type which I really hate! I always end up with one side out of line with the other, I had to keep tweeking them for about 5 minutes before I got them them lined up properly!

I found a video of a modern built Dragonfly in flight.

This one is powered by a PAW .09 diesel, and seems to fly quite fast on that engine, although it certainly seems very stable at low speed