RC DeltaGliderIV project

[RisingFury]

Some time ago I got the idea that I would (within limits) recreate the DeltaGliderIV. I gave a lot of thought into which of the Orbiter vessels I'd recreate as a remote control airplane and I came to the conclusion that the DeltaGlider possesses the best flight characteristics. By nature, delta wings fly very stable, have a large tolerance for shifting CG and have a very high lift. Also, delta wings that are the same length as their wingspan usually fly very steady on roll and pitch control.

The DeltaGliderIV would due to it's low poly and no rounded edges be a very simple and easy construction, as well as low weight.

So I decided to learn AutoCAD and draw a simple blueprint. The paintjob will be mostly Mining DGIV combined with blue around the cockpit and white cockpit as on the Rescue glider.



Instead of a dual rocket engine, she will be powered by an electric motor. A 1100 kV outrunner with a 13x6 propeller on it. Producing around 25N of thrust, it will be capable of launching her vertically up and still capable of around 100 km/h flying straight.

A 2200 mAh, 3 cell, 25 C LiPo battery will provide around 3.5 minutes of flight time under full thrust. At full throttle while held down, the engine will burn around 55 A, in flight around 35 - 40 so a 60 A speed control will ensure everything runs without smoke from the electric parts.



Now... I used DeltaGliderIV from Orbiter as a reference point, but ended up doing some modifications:
- Larger vertical stailizers. Planes like vertical stabilizers...
- Larger control surfaces both on the wings and on the stabilizers.
- "Straighter" wings. If you look at the real DGIV, you'll notice thick wing close to the body and thin wing at the tips. I modified that so that the wing is almost the same thickness on all parts. That eliminated a lot of construction problems and reduced drag at the same time.
- Slight modifications to the underside of the body for easier constructon and better structural strength.


I'm ordering wood and coverfoil this week and construction starts on the next weekend. I thought I'd keep you guys posted, so I'll be uploading pics / videos of the build and flight.


The blueprint isn't fully done yet. I still have to modify some things and clean the whole thing up (and label everything if I decide to release the plans...), but I thought I'd post what I have so far:

 

[jgrillo2002]

Sounds like a great idea man. have fun, take it slow, have fun, and Good luck

 

[RisingFury]

Ok, finally finished the DeltaGliderIV blueprint. Also have a pic of the paint job:

I ordered the wood and a bunch of other things yesterday. If everything is in stock and arrives by Friday, I'll start the build this weekend.

 

[astrosammy]

Wow, what a great project! Will it have UMMU, and an ejection seat? :lol:

Good luck, looking forward to see it flying. What scale will it have?

 

[Urwumpe]

hmm... i wonder if you can't fit bipropellant engines on a RC DG... getting the needed thrust should be possible, the question is just for how long...

 

[RisingFury]

I won't put a rocket engine on it... although it has crossed my mind to make a sugar + KNO3 motor...
I'm putting a powerful electric motor with a 13x6 prop on it. It will have about 25 N of thrust, which will be enough to lift my vertically up and will fly for about 3.5 minutes on full thrust.

 

[MeDiCS]

Wow, this is very cool . What will be next, an XR-5? Looking forward for a few photos

 

[RisingFury]

Wow, this is very cool . What will be next, an XR-5? Looking forward for a few photos

I was wondering when someone would ask that. I've thought about it.
XR2 is definitely out of the picture. It's effective wing area is far too small and the wings are in the back which would (even if you got it into the air) make it so nose heavy it'd just dive straight down.

XR5 is probably a borderline case though and might fly, providing I use a "normal" airfoil and not a relaxed one like for the DGIV, which would shift the point where the lift force acts on the wing forwards a little bit. Also I'd have to make the nose light and load the back with propulsion and radio equipment.

The construction of the XR5 would also be quit difficult, due to all the curved surfaces... I'd have to use a lot of balsa and sand it down round it up, but that isn't exactly weight control...

We'll see. First I'll build the DGIV, then I have a 2 m wingspan Extra 300 planned and then we'll see...

 

[MeDiCS]

I was wondering when someone would ask that.

It isn't hard to figure that out, DGIV and the XR series are the favourite winged spacecrafts here . If I had the skillz (and materials, and time) I'd certainly try to build it .
Anyway, still waiting for the pics :speakcool:.

 

[RisingFury]

RC has become pretty available lately. They now sell everything... however, if you go into RC, I advise you build stuff yourself. I'm building this from wood. Balsa and some other wood... I think Birch cos it's light and strong. The wood won't cost you much and you don't really need too much skill to build something. You just have to get one of those U handle saw, some wood glue and some sanding paper. And of course the blueprint. The easiest way to actually build is to glue the blueprint onto the wood and then just trace the lines with your saw, sand it all up and glue it all together.

Though if you're only getting started, consider a free flying kit that you just mostly glue together. That is really cheap and gives you a lot of fun. I started out with one of those and if I got lucky, it would glide for over 5 minutes when just throwing it from your hand.


I will be putting up pics of the build and of course the flights.

 

[Mafuskas]

Sounds very interesting! I hope the build goes well for you and that the flying goes even better.

I've never really considered going into RC flying as a hobby, but this discussion has certainly peaked my interest. Perhaps I will look into it more.

 

[RisingFury]

I couldn't find the A1 model that I started out with, but this is similar:

On a day with good thermal conditions, there's a chance this will fly away and you'll never see it again.

The model I had had a tiny rudder that made it go in circles and an elevator that would pop up to act as an air break, which was connected to a mechanical clock. Once the time run out, the air break would pup up and it would bring your glider down again.

 

[RisingFury]

And so it begins!

On Wednesday I finally got the wood that I ordered.

From top to bottom:
- 4 mm x 1000 mm x 250 mm birch plywood
- Black, red and white foil used to cover the plane (they run out of yellow one... I'll have to get it elsewhere)
- 10 mm x 1060 mm x 100 mm balsa wood
- 1.5 mm x 1000 mm x 100 mm balsa

So I started cutting out the wood. The bottom and sides will have a strong plywood construction, but because this material is really heavy, I've cut A LOT of holes in it. It doesn't really degrade the structural integrity, but gets rid of the weight.

And after two days of work, here's where I am at:

All the fuselage supports are cut out. I have to redo the last one cos it's too narrow, and I have to cut out the motor mount, which will come later on.

The thing is just (poorly) taped together right now so I can better visualize the body, verify my dimensions and a photo-op, of course

The top in the picture is the nose, the bottom is the rear.


The biggest challenge on this project will be to keep the weight down below 2 kg. I'm getting a motor and propeller that will produce 2.4 kg of thrust and I want it to go vertical. The body so far (not counting the two unfinished side panels) weighs in at just over 200 g. The electronics - battery, motor, 3 servos, propeller, wires, receiver weigh around 600 g together, so I've already blown nearly half of my weight budget.

I'm estimating the body will weigh in at around 600 g without the electronics... so I have to squeeze the wings into 400 g each. Should be doable.

 

[Sky Captain]

This is very cool, can`t wait to see it flying. Good luck!

 

[RisingFury]

After another day of hard work, I've made some significant progress.
I managed to cut out 4 new pieces and apply weigh saving measures to the ones I could finish yesterday.

I've put the frame together so that I can verify my measurements. I've only made one small mistake, but that's fixable, so no worries.

As you can see from the pics below, the frame is held together by string. It's not glued yet...

Currently the weigh of the frame is at 400g and the weight of the balsa covering is around 200g, but unfortunately, it's not complete. The nosecone is missing and some more structure is missing. Also, if I take into account the covering foil and finishing touches, the weight will be brought up to around 750g - 800g, which is 150g - 200g over the planned weight.

I've also done a good estimate on the weight of the wings and they look to be around 400g each, due to plywood construction.

I want to keep the weight of the plane at a maximum of 2 kg, so I'll need to apply some more weight saving measures. This is proving to be quite an engineering challenge and is a lot of fun to build.

The plane has such a strong (and heavy) construction because I want it to survive excessively high G-forces and fast dives. I wanna see how it behaves at high speed and in a tight pull-up maneuver right before the ground...

I won't be working on it till Sunday evening / Monday morning, but when I do, I'll keep you posted. I should have the body done by Wednesday

 

[n72.75]

becaues of its wood construction, don't make steep reentries.

> 0.3 degrees should do it.:lol:

 

[Dambuster]

"
The plane has such a strong (and heavy) construction because I want it to survive excessively high G-forces and fast dives. I wanna see how it behaves at high speed and in a tight pull-up maneuver right before the ground..."

Please be careful!!! This RC plane is really amazing & cool!!!!

Do you plan to produce plans on how to build this? If so, there could soon be a whole fleet of DG-IV's popping up around the world

 

[RisingFury]

Thanks!

I have the whole blueprint drawn up in AutoCAD

I will be releasing the plans once the RC DGIV is done and flying well... and I've made some annotations to the plans and some additional modifications to make it friendlier to read.

Yea, I will be careful with it. I don't wanna crash it. I'm planning to make a cool video once she's done and flying.

 

[RisingFury]

Just a boring update:

I've got all the plywood construction wood cut out now and have started gluing it together. I'll have a few pics up in a few days when it's all glued together.

Currently I'm estimating the weight to be some 200g too much.
If the thrust is at 26 N, I should get away with it... if not, I can still put a bigger prop with less pitch on to compensate. 14x5, I guess... but it would create more torque...

I can still do a couple of things to bring the weight down, but not 200g. I'm estimating the weight of each wing to be around 400g, but I'll do my best to keep the weight down.

I was thinking about making a landing gear, but I doubt I'll be able to do that.

Anyways... more pics in a few days.

 

[ripley1]

Looking great,best wishes with the project.Please keep us updated.