DTF Chuck Glider

[Exponential]

I was recently asked to do a build and fly with a local girl Scout troop, and the leader asked for a glider as the build. A search of the internet didn't really show much by way of simple, easy to build foam gliders so I set up the following criteria:

1. No more than 3 parts
2. DTF (what else!)
3. No cuts longer than 12" so a 1' steel ruler can be used
4. Flat plate
5. No tabs or slots
6. Flies reasonably indoors.
7. A novice can do it with some supervision.
9. Virtually indestructible. Okay, almost indestructible.
10. At least a little cool looking.

I had recently heard the FT podcast that talked about a simple chuck glider for kids, and I thought I'd try my hand at it, using the criteria. I started with the design of chaosMurphy in Bluecor based on one of the Kline paper airplanes, with the intent of using the KF airfoil to help make the design floatier, knowing it would be a little heavier in DTF.

The first attempts fared poorly with the standard dimension KFm2 foil on a diamond-shaped wing, and I then cut in the trailing edges to get more like the design I had seen in chaosMurphy's postings. Still not good, with too much pitch instability. I then added extended F15-like horizontal stabilizer extensions to get more moment; this was better but still pitched up too much. Adding more weight to the nose fixed the pitch, but it flared at the end of the glide and stalled. Maybe the KFm2 was providing too much lift, but removing them made things much worse. Since I had spray-glued the KFm2 steps in place, I started resizing them smaller and moving them around the wing until I got reasonable performance, still with some stall tendencies. I moved the launch skeg forward to reduce pitch-up on launching, and decided to model what I had in Sketchup and print some flat plans to do a DTF build.

The resulting plane had a slightly worse tendency to balloon on launch, and more nose weight helped a bit (up to 4 pennies by now!) The next variable to tune was the dihedral angle, and this proved important. reducing dihedral made the design balloon less, and at the current design angle it performs about as well as I need it to - one wall to the other in a gym. The design is simple enough that anyone can modify it and I'd encourage you to try your hand at improving the flight characteristics. I'm sure it could be made better with more tweaking.
View attachment 19857

Here's the build:
Bluecor tester, with moveable KFm plates:



And now the DTF build. The centerline is a cut almost all the way through, and I put a bead of hot glue on the back of and skimmed with a piece of scrap to make a strong midline:


These are the folds that attach the wings to the fuselage:


Now fold the fuse down the midline so the skimmed surface is on the inside. Skim the exposed top of the fusealge with hot glue to provide a sturdy top line:


Glue the KFm2 plates in, push the plate back so the paper is stretched out, it will form a nice angle on the top:


Glue on the little back plate to hold the angle of the fuse, and then the vertical stabilizer on top:


The throwing skeg is glued into the underside with the back end at 3 inches from the nose.


Final form. I used 5 pennies, with a dab of hot glue between and then taped into the nose.


Lastly, gluing a bit of skewer in the nose will reduce the damage from hard landings:


Have fun with it, let me know if the plans aren't scaled appropriately and I'll fix them. Use four (4) pennies in the nose.
Exponential

 

[xuzme720]

Nice project! I'll need to give this one a try with the granddaughters.

 

[Exponential]

xuzme720: I'd be happy to hear how yours turn out and what you did to make it fly better! I have found that my best flight results are to aim the glider slightly up and throw firmly. The nice thing about the skeg is that you have the thrower place their index finger at the back and clasp the sides with thumb and second finger, then tell them to choose a target at a 20 degree angle or so above them - and end their throw by pointing at the target with their index finger.

Looks like I can't post the Sketchup files, if anyone wants them please PM me.

Exponential

 

[rcspaceflight]

Looks like I can't post the Sketchup files,

You have to click on "Go Advanced" under the post quick reply box. Then there will be extra buttons above the text input box. The button with a paper clip on it is the "Attachments" button and will open up a pop up window. Then you can "Add Files". After that then click the "Insert Line" button on the bottom, then "Done".

 

[xuzme720]

xuzme720: I'd be happy to hear how yours turn out and what you did to make it fly better! I have found that my best flight results are to aim the glider slightly up and throw firmly. The nice thing about the skeg is that you have the thrower place their index finger at the back and clasp the sides with thumb and second finger, then tell them to choose a target at a 20 degree angle or so above them - and end their throw by pointing at the target with their index finger.

Looks like I can't post the Sketchup files, if anyone wants them please PM me.

Exponential

I'll be sure to let you know how it goes. It might be awhile since they have dance, scouts, gymnastics and swimming coming up...hard to grab some time with them these days...

 

[Exponential]

I've been working on the flight duration, and to reduce wing loading I've downsized the vertical stabilizer and removed a penny from the front so we're down to four pennies, the result of which is that the hang time is improved quite a bit, at least by 25%. The glide is flatter, and looks more "pretty". The plans in the first post have been updated to reflect the new stabilizer, although the pictures still show the old one.

Expo

 

[OrangutangSurfer]

I made a 13" wingspan plane for my daughter to throw around it was pretty simple... I used the profile shape from the FT racer, you can print the full size plans just scale to fit 8.5x11 paper, cut out the main parts then trace them on DTF and cut out. I just used the profile part of the fuselage and drew in my own canopy before cutting. I had to of course make a few mods.

1st I cut 3 fuselage pieces one full sized then 2 more that cut off about a little more then 3/4 length to the tail section. I took the wing shape and added a little length, my science is a little weak but gliders have larger wings and I wanted this to glide well so there for I made the wings longer. I cut a space for the wings to slide through but you could probably cut out a rectangle on the bottom of the plane and just glue them in place. I used an iron to make a 45 degree angle on the front of the wing and maybe a 15 degree on the back to create an airfoil. I assumed if I had just scaled the plane down there was no reason the CG should have been in a different spot so I took some machine screws of various sizes and started screwing them in the front of the plane. i used 2 to finally get the CG about right. they also protected the nose when it landed nose first.

I would say it flew as good as any 4-5 dollar plane you get at the toy store, my daughter loved it.

-Jes


I will probably make another one soon and this time try the spitfire I'm going to try to keep it more true to the shape of the plans and will iron the airfoil on the wing before I glue it to the plane. I also am going to attempt to pull the rubber-band propeller from her totaled plane and somehow rig it to work with one of these. I'll add pics if I ever get to it.

 

[OrangutangSurfer]

Also....

When I first found Flitetest I was so excited to build a plane I printed the full sized plans scaled down on 2 pieces of card stock here's the result. I used 2 magnets on the nose to balance the plane, this is by far the COOLEST paper airplane I have ever made. glides across the living room all the way to the wall. I was surprised it flew so well with all the tape it took to keep the pieces together, I also used ES300 (i think that's what it's called) to glue some parts in place

 

[Exponential]

Very nice, both of them! I hadn't given a thought to the cardstock method, but it may be a bit complicated as a first build with the Girl Scouts as they will likely have little prior airplane building experience and we have two hours to make a go of it with 10 participants and one or two skilled builders supervising. The FT Racer would be approachable at 5 or 6 pieces, more involved than the DTF Chuck Glider but closer to a conventional glider. Did you use a two-piece wing?

Expo

 

[Snardo]

For another option that, admittedly is not nearly as "cool" looking, but would be very simple for any kid to make, google "FG9 glider" or "FG9 foam plate glider". It's a very simple plan that can be made with scissors, tape, a styrofoam plate and a penny for balance. We use them at our club community day every year to give the kids something to do and to take home. They're always a hit!