Brodak Yak 9

[Motorman]

Anyone build the 325 sq in Yak 9 from Brodak. Just wondering if it has a solid LE and what engine you put on it.

Thanks,
MM

[Bill Little]

Hi Walt,

John hasn't used solid LE in his kits in years.

BIG Bear
RNMM/AMM

[Carl Cisneros]

I am getting ready to build the Yak9 also motorman.
It is the one that is toted as the Sterling one.

It has the Brodak V style (or sheeted type) trailing edge and the square (if you will) leading edge that has to be sanded to shape.
That is no problem with 80 grit to get the initial shape then 120 and finally 320-400.

Mine is going to be powered by a SLIGHTLY De-tuned ST 45X on a bolly pipe.
YEAH-YEAH, I know   OVER KILL LOL  

My plan is for OTS with this at Brodaks this coming year.

Got your e-mail on the little Cox speed

Carl

[Ron Cribbs]

45!

Goodness, even detuned it's going to be a handful. I imagine it will be very nose heavy as well. Anyway, when you get it done take some video as I would love to see it!

Ron

[Carl Cisneros]

Am planning on doing just that guy.   

[Motorman]

What's the wing area on the Sterling Yak about 400? I've got a nice 3 bolt Fox 19 I think will be good for the Brodak kit.

MM

[Randy Cuberly]

Whoa...an ST45X on a tiny little profile...with a pipe yet...Crazy...seriously crazy...Why in heavens name would you do something like that...It'll probably take about 4-5 oz of tail weight to get the CG in a reasonable place.  Make sure you beef up the front of the Fuselage and the Fuse to Wing joint. 
Again Why!
This is a fun airplane (not really super stunt, but fun) with something like an OS25 FP or LA.

Crazy...

Randy Cuberly

[Motorman]

A ST45X on a pipe could easily achieve 130+mph if you set it up to go fast, that would be awesome. I would hope you'll have a control system that can take the pull.

MM

[Randy Cuberly]

A ST45X on a pipe could easily achieve 130+mph if you set it up to go fast, that would be awesome. I would hope you'll have a control system that can take the pull.

MM

Not to mention strong arms and good aerobic conditioning!

In the past I flew Slow rat racers that were in this ballpark  at about 135 mph...Fun...Well that depends on your definition of fun!
I'm too old to even consider something like that now, but it will definitely give you a physical workout.  If you haven't done it, just go pick up a 50 lb tool box and jog (fast) in place with it for about 5 minutes!

Randy Cuberly

[Ron Cribbs]

I had the opportunity to fly a Yak-9 (Sterling version) last week. It's very small at 323sq" it was powered by a '58 Fox .35 and it had plenty of power.

For what it is, I found it to be well mannered plane, probably capable of doing the pattern, but not as pretty as a modern PA stunter.

I am curious to see what a .45 engine does in a Yak. I hope it gets built. I think it's crazy, but I am a little intrigued!

I think Walt's original question has been answered, sorry for the hijack, just couldn't resist this time.

Ron

[Perry Rose]

I built the Brodak kit and used an O.S. .25LA. A good combination.

[Carl Cisneros]

IF I do change my mind on the ST 45X, I have an couple of OS 30S, an OS 35S,Series 21 McCoy 19, 35 and a couple 40's (all new in box),K&B Stallion 35 (new in box and balanced), Enya 19V that can be put to use in the plane.
More than likely I will change my mind on the 45X tho, I checked the exhaust/tank clearance a little bit ago in the garage and it will not work.
So, I am open for suggestions guys.............  anyone got an idea for a motor for me from my list I should use?

Thanks in advance.

Carl

[Dennis Adamisin]

The Yak-9 is small with a thin wing.  It needs to be light.  Mine was electric and weighted in at 29 oz.  I would not want it to be much heavier.  The ST 45X is a boat anchor.  As for using it in the Yak, all I can say is that you can put a candle in a cow pie but that don't make it a birthday cake!

Of the engines you listed I would recommend the Enya 19.

BTW, I designed a dihedral & wing mounted LG kit for the Brodak Yak (parts won't fit the old Sterling)that works on the IC or Electric versions.  It is Conversion Kit #BH-1933.

[Glenn (Gravitywell) Reach]

Definitely the McCoy 35.  I had one on mine way back when and it was a fun plane/motor combo.  Would love to do it again.

[pat king]

If you want a Yak 9 for your 45 look at my Yak 9 - 45. The airplane has a 52" wingspan and 532 square inches of wing area. The airfoil is 16.5% thick (the wing is 1 3/4 thick at the root). The airplane is designed with dihedral and wing mounted gear. The plans explain how to build it without dihedral. If built without dihedral the leadouts are definitely below the vertical CG.

Pat

[Carl Cisneros]

Hey guys

We are hi-jacking MM thread here so will start a fresh one and continue there.


Sorry about that MM.