Category Archives: Vintage F3A

Yoshioka Aladdin update

The wonderfully strange Yoshioka Aladdin 45L that I built in the autumn of 2012 has finally flown, after hanging on my wall for almost three years (That’s what family life can do to ones hobby). The first flight was highly successful. After some trimming, it flew hands off straight and level. The engine, an old but well looked after YS .63 FZ ran rich but did not stop. It has ample power, it’s not a rocket, but it pulls it along with enthusiasm. The sight of the sleek plane with the fourstroke sound was very strange. It looks like a pattern plane and sounds like a scale model.

The Aladdin has a very strange feature, an offset engine installation. It is explained in the poorly translated Japanese instructions that mounting the engine like this does not require any right thrust. It looks very odd, and gives the plane its trademark appearance. See here:
Offset! It’s mounted 90 degrees to the models centreline. The benefit, apart from the obvious fact that the engine and muffler are almost completely buried in the cowling and not hanging out the side, is that right thrust will vary with engine RPM, and this setup will not. I have just the one flight, but I could see no apparent problems in the air, it certainly flew straight enough. Perhaps it really does work? But if so, why haven’t others done the same? Comments?

Here are the build photos.

Killer Kaos flies (restomod part 5)

2015-08-05 21.37.44

The O.S engine gave me a little headache. I ran it at home a little bit, and it ran strong and started like any O.S motor should, i.e. with a light flip of the prop. It tached 10.000 rpm on the APC 11×12 and idled smoothly. All was well and then I tried holding the nose up, and it leaned out badly. A lot of tweaking later, I was unable to fix it. I re-did the fuel plumbing and moved the tank a lot further forward and hoped that would solve it. It may have been optimistic having the tank as far back as I did without using a pump or header tank.

On the field yesterday I had exactly the same problems. I switched from an O.S 8 plug to an OS F, and that did nothing. I tried a smaller prop, an 11×9, and that helped a bit. I then tuned it some more and eventually it ran strong. I had one flight where I landed early because I could hear it leaning out a bit in loops, tuned more, and then suddenly it ran like nothing else mattered, not missing a beat going up, down, sideways or anything. Success! The third flight was suddenly bad again, leaning out. Landed in a hurry, tuned, and suddenly it ran great again.

I have a successful track record of making stubborn engines run good, and I don’t intend to let this one beat me. I suspect the pipe is slightly too long, and I think shortening it might do the trick. I will also try an 11×10 to load it up just a bit more.

The plane flew just like you’d expect. I had some wild deja vu’s while flying. I have lots of flights on the old version of it, so it behaved as I remembered, which is a strange sensation when I was mentally prepared for a maiden flight! I was also surprised at how well behaved it was on takeoff and landing, and how well it tracked straight and level. It has no vices whatsoever.

Here’s a before/after photo, with at least 13 years between the two:


All the pictures from the project can be found here:

The restomod project blogposts:
Restomod part 1
Restomod part 2
Restomod part 3
Restomod part 4

Killer Kaos restomod part 4


The Killer Kaos is covered and painted. I used Tamiya Lexan spray cans to paint over the white Oracover. Before painting, I gently scruffed the Oracover with 1000-grit sandpaper, which makes it less glossy without scratching it.

Tamiya lexan spray paint covers well and is easy to work with.

To avoid paint seeping under the masking tape like shown above, here’s a trick I use:

Spray a coat of clear, flat paint first. If any clear paint bleeds under the tape, it won’t show, and it fills the edge so that the color coat will not bleed under. 

A perfect result

The undercarriage looked completely hopeless.

I cut the legs and added a pair of Great Planes axels. It now sits lower and has a perfect stance with clearance for up to 12 inch props.

Tettra 55 mm wheels look great

I repainted an old field box to match

Some stickers


Next up is hooking up the control surfaces in the tail, mounting engine and pipe, and the tank plumbing.

Killer Kaos restomod part 3

The finished radio bay in the fuselage

My favourite part of any build is the pushrod mechanicals, the electronics and engine installation and so I take my time getting it as perfect as I can. I ground out a huge cutout for the Tettra 400cc tank in the fuselage former. The tank would fit in front in the tank bay, but I wanted it further back in order to not have the CG shift in flight due to the tank being emptied.

The Tettra 400 cc Crank Tank fitted. 

The servos were moved forward from their original position and the battery sits behind them, in order to fix a CG issue that the plane had back in the day. Because of that, the pushrods had to be lengthened. I wanted to stick with the original Carbon Dubro pushrods that were already in there, so I simply added a longer threaded rod that extends a bit into the pushrod inner and outer tubes. It adds a little bit of weight, but it adds it behind the CG where I need that weight, and as a bonus it stiffens everything up a little more. BLS451 servos were bought very cheap from a chopper guy switching to HV gear. They are great servos, so I get them whenever I see them up for sale. The throttleservo is a Dymond metal gear digital midi.

To top everything off, I fuel proofed everything using flat black enamel paint, which also looks cool. I’m very happy with how the interior bits and pieces turned out.

The radio bay. Note Tettra switch mount bracket

The aileron linkages. I used a pair of trusty old 9154s that have over 400 flights but are still pretty solid. I added plywood inserts to the ailerons so that the screws have something to bite in. I shortened some Futaba servo screws to fit, as I didn’t want anything visible on the upper side of the ailerons.


The O.S .61 SF engine was fitted in order to get the throttle linkage hooked up. The intake is finished. It’s a lot of motor for so small a nose. 


Killer Kaos Restomod part 2


This is part two of the Restomod-project. Check out the new tail (above). I made a new fin and rudder, new elevators and modified the stab tips to make everything nice and uniform. I wanted to get rid of the pointy, tall fin and elevators. It’s not radically different, but a lot cooler. The fin and rudder are almost 2 cm lower, something that will tie in nicely with the overall stance of the plane when it’s done. I have more changes in mind!

This has been a tough decision, but I’ve decided to go with a standard Kaos 40 canopy (The plain Tower Hobbies $3 canopy) instead of the long Killer Kaos canopy. It’ll be a whole new look. I wanted to loose the 1990’s styling, and this just looks a whole lot cooler!

You can see comparisons of the old and new tail, plus how it looks with the old canopy compared to the new one in the builds photo album.

Killer Kaos Restomod

kaos original
The original back in its day, about 15 years ago. I’m gonna loose the horrible 1990s color scheme and canopy and make it cool again!

I’m a fan of the Kaos series of planes and got a Killer Kaos* kit around 1998. I remember ordering it by e-mail directly from Joe Bridi, and that it was a very impressive kit with all sawn and sanded parts. He gladly offered advice on building and engine choice, although he disapproved of my choice to mount the engine upright. Well guess what Joe, that’s about to change!

I flew this plane a lot for four full summers, and learned a great deal. It was in fact the fist pattern plane that I never crashed. It was a good, solid flier. Eventually the ailerons came loose and I had plans to do a lot of fixes to it that I never got round to, other planes having taken its place as I started competing actively in F3A. It was sold to a friend in 2004.
I came across an O.S 61 SF last year and had no idea what to put it in, so I gave my friend a call, and it turned out he still had the model, preserved exactly the way it was when he got it. I bought it back, and now it’s never gonna be sold again.

So now I have a completely original, unrestored Bridi Kaos. It’s straight, light, well built (I was surprised at old selfs abilities, I didn’t realize I put that much effort into it back then) and it deserves a complete restoration. Also, I have come to realize that the spirit of the Kaos-line requires a bit of modification, so I’m gonna do that Hot-Rod builders call a restomod, which is short for restoration and modification. And I’m gonna have a ball doing it. It’s gonna be fast and not very loud, it’s actually gonna be kinda fast ‘n’ quiet!

My plans for it includes:
– New engine (an O.S 61 SF) and a spanking new Hatori 650 pipe and header
– Completely new covering and color scheme
– Lighter and better digial servos
– Rebuild the nose to mount the engine on its side
– New and different wing tips
– Individual aileron servos

Enough talk. Here are the pictures!

* Some Kaos trivia: The Kaos name was sold to Great Planes in the 80’s when they produced the Trainer 20-60, Kaos 60 and Super Kaos 40-60. After that, Joe Bridi continued to design other versions, but changed the name to Chaos with Ch. Utter Chaos and Killer Chaos to name a few. I never got used to that and so I still call all planes in the series Kaos with a K. Designed by pattern Legend Joe Bridi, the Kaos appeared in RCM magazine in 1970 and the streamlined long-nose Super Kaos with retracts came in 1973 in RCM magazine. That’s a looong time ago and it’s still cool! After Great Planes started kitting the Kaos, Don Anderson created the legendary Ultra Sport which is essentially a Kaos with a turtledeck.

F3A Vintage Rosentalpokal 2014

Photo by
Photo by  Karlheinz Gatschnig,

The vintage F3A meet Rosentalpokal is flown using models from around 1975, in Carinthia, Austria. Karlheinz Gatschnig was there and took some wonderful photos.
The event was also covered by FMT magazine and in issue 3/2014 (PDF)
Notice the big Dalotel pictured. It is a prototype of an ARF that will be available from Schweighofer. It exactly replicates Hanno Prettners original Tournament of Champions Dalotel.
See all the photos from Karlheinz Gatschnig here