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Fullfilling the dream... the ultimate rubber powered airplane

Daniel Kezar

Ultimate Cheap Skate

This is super-awesome project and I'm glad it's all coming together!

Say, are you bringing this gentle beast to West Baden?
If so, we wish it safe travels and hope to see it.

It'll be my first time spectating a free-flight event and should prove to be quite interesting, entertaining, and educational for me. We're looking forward to meeting up with you there-- it should be fun.
please film! that is going to be an incredible meetup!


Free Flight Indoorist
Quick advertisement for those who haven't seen it: I'll be collabing with NighthawkGliders at the Jim Richmond Open this weekend. Not only will we be playing with gliders, but this kit will be present, and the prototype Hourglass II, and the microfilm models and all of it. Yes, we're going to have a gathering of the ultimate indoor stuff!

Moving on...

Here's a first: a kit that includes a preassembled bracing jig for the wire bracing. Hourglass II prototype shown to clarify its usage.



And we have covering frames (and other cool stuff)

I finally got around to slotting the outer panels of the wing template. I'm going to tweak the laser files for Hope's build so we don't have to deal with that particular issue anymore.

The prop, wing, and stab ribs are all there...

And packed safely away

Here are the forming mandrels for the motorstick, stick extension, and tapered tailboom.

For those wondering how all that mandrel stuff works out, here's a video:

Another first for a kit: preglued boron. The little drawplate in the middle there is filled with duco cement and the boron is drawn through it to coat it with a thin coat of glue. It's bonded to the tubes by laying it in place and hitting it with drops of acetone. The effect is very quick, and it stiffens the fuselage drastically.

Here's a tutorial on the coating:

Mechanical bits in a bag: bearing, hook, wing and stab posts (.027" cf tubes), tissue tubes, and oh yeah, a J&H Aerospace variable pitch prop hub!

Here's a tutorial on how we mount the bearings into the motorstick:

And I'll leave you for today with this little fun bit. We had a Hangar Rat contest at our monthly indoor meet on Saturday. I won the mass launch, and Dohrm Crawford (holding his model over my head) won the timed event (best three out of 6 flights). Dohrm is a Vietnam vet, having flown Cessna Bird Dogs in combat. He later flew F-4s in the reserves and then went on to F-15s before transitioning into a very successful career at Delta, retiring some years back as a 777 captain. His pension got yanked when Delta got themselves upside down, so he worked another five years as a sim instructor before retiring again last year. He's been building like a madman ever since!

My mass launch flight was 2:19, and Dohrm's winning series were all in the 2:50 range. Not bad for a tissue covered model with a balsa plank prop
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Free Flight Indoorist
I'm baaaaack!!!!!

So folks wanted lots of footage. Well, I got some, but absolutely nothing at the level of this:

I'll try to post more from my own work later, but Nighthawk Gliders did a really sweet job. I did livestream important points of the contest on the Free Flight Digest facebook page and y'all should take a look at that for a play-by-play.


Free Flight Indoorist
My Ukranian-American-Canadian flying buddy agreed that the weather was bad and funny hats weren't enough to fix it.

The Canadians taught us how to mold tapered spars the easy way. I'll be making use of that...

American junior team member Ross Clements showed up with a fun toy. Yes, it flew. And I do have video.

Germany's Thomas Merkt makes really, really nice tools. And planes.

And his model box is awesome:

Thomasz Momot has no fear where composite structures are concerned

Ranier Lotz of Switzerland is a true craftsman and makes some really cool VP hubs (and crazy drooped tail models):

My nemesis was in appearance, Mr. Kazumasa Kihara of Japan. Kihara-san showed great skill in flying by flying over 23 minutes in the final round on a fixed pitch prop! Not surprising though for a man who flew 39 minutes with a microfilm model under a 26' ceiling. He is the man!


Fly Angry
Cool event Josh. Over all you guys did pretty good I would say. There was a lot of old timers there with crazy experience to go up against. that seemed to be a treacherous place to fly something so delicate with all them hazards so I am sure luck played a lot into how well people did by avoiding them.

The Night Hawk team did a good job on that video too. Well done to all. :applause:


Free Flight Indoorist
No, I'm not done. Because I've done actual Unlimited class design work!

Meet Hourglass III, one of the largest indoor models ever attempted. Oh yeah.
Hourglass IIIprelim.png


Enjoy Flight & Enjoy Life

In this Unlimited Class... is the size of (everything) unlimited-- including the rubber motor?

Your Hourglass III is crazy! A 5 ft wingspan!?! wow!
So, bigger is better to get longer flight times?

I was wondering if one of the goals was to achieve lower wing loading for longer flight duration.


Maneuvering With Purpose
Very cool stuff. My own experience is limited to a pair of AMA Cubs when I was about 9 yo :p

I was always captivated by the ultra-low RPM of those props. I like the way y'all use the balloons to manage the confined space.


Hostage Taker of Quads
Cool . . . But a pain to steer them that way. Floppy 15m+ carbon casting poles are way easier than balloons, but when the ceilings get this high, it won't take long to climb way over that . . . And you're stuck using the balloons . . . Or letting it just fly where it will go . . .

So the balloons are a necessary evil ;)


Hostage Taker of Quads
um . . . 15m+

I don't own one . . . yet, but the long carp baiting poles popular in Europe (apparently) are a common tool around our club indoor site (a Cat I church gymnasium). I've borrowed them on occasion for the "this one's a really good flight!" moments . . . and the "now how am I gonna get that sucker down?!?" moments. I'm trying to find one around 18m that's not outrageously expensive, but I'll probably have to settle for a shorter one.

As for seeing one, FAI-F1D may have a pic or two, but I'm shocked I'm coming up empty handed. I coulda sworn I had an extortion pic of him standing on a stacked pair of folding tables trying to steer a model with a 12m pole . . .


Free Flight Indoorist
Huh. Only one response. Maybe the intelligent thing to do would be to post actual content. And since I don't have any, I'm going to post screen grabs of updated plans and templates

Corrected plans showing floating stab and bracing:
2018-04-02 13_20_18-Hourglass II.skp - SketchUp Make 2016.png

Plans compressed for printing. I printed this thing out and good grief it's huge!!!
2018-04-02 13_16_54-Hourglass II.skp - SketchUp Make 2016.png

Templates in full size. Again, absolutely huge. This thing has double the wing area of one of my DLGs. There are two meter gliders with less wing area than this monster!
2018-04-02 13_17_50-Hourglass II.skp - SketchUp Make 2016.png

Templates broken down for laser cutting:
2018-04-02 13_18_24-Hourglass II.skp - SketchUp Make 2016.png

I've mostly caught up with orders that came in during West Baden, so hopefully I'll get started building this rascal soon.