40% 118" Yak 55 (Hempel)

[toc pilot]

Hello all,

I figured I'd start my own build thread on this 40% Yak 55. There is a 100cc forum for these but nothing yet on the 40% one. So here it is. I am putting this plane together for the 2010 IMAC contest season (yes, I know... Iam late already). I hope to make the maiden tomorrow (3-14) as there are only a few items remaining. There is a contest next weekend called "The Cactus Classic" in Phx.... we'll see if the plane flys well by then without practice .

Ok, the airplane has a 118" WS but the fuselage is pretty big. The cowling is 15 3/8" diameter! My airplane will have the 3W-170 motor in it. Everything I have done is stock except for the flooring, I have added vinyl graphic material to give it the C/F look.... looks cool to me! Now, I am using a lot of high $$ accesories to bling, b ling it and also to make it overall, lighter. The custom wheels I am using are from Air-Man Wheels, these are the coolest ever and they were over 4 ounce lighter than using Du-bro's wheels and axles. Other equipment used for weight reduction are the Fromeco Lithium Pollys (2-2600Mah for rx) and a Fromeco 2-cell 7.4v Ion for ignition, single Futaba 2.4 RX, 9 servos total with 2-each aileron, 1-each elevator and 2 on rudder plus throttle.

I have not weighed the airframe yet but I think (hope) it will be light. Each compleated wing panel weighs: 3lbs - 1 ounce. Is this good? Someone weigh your 40% wing and tell me if it is in the ball-park.

Here are some pictures, Enjoy!

Bill Hempel

[venom89]

Looks good Bill. I've been waiting on some info on this one!

[gforce]

Each compleated wing panel weighs: 3lbs - 1 ounce. Is this good? Someone weigh your 40% wing and tell me if it is in the ball-park.

Seems dang light to me mate,do a bleeeeeender and see if they stay there.Heck Bill,you only need one wing anyway right lolol!! Just josh'in ya bud! That 40 cent'er 55 looks dang sweet to me.Love the colors too

Good price also!

[smokin]

looks nice bill! good luck with this baby....not that you'll need it!

[KTS]

Looks great Bill! Any chance you will bring this to Nall?

[toc pilot]

Wow.... the last few things are taking forever. The canister mounts were a pain but after a few hours I have finally got them in and everything fits. It took a little bit of fabricating and hacking of the standard 'hangers' but I figured out a way for the cans to work, good thing as I really didnt want to run mufflers. All though, mufflers may come into play later as they are always the lightest set-up. Right now, the cans and SS (flexible) headers weigh 2lbs 15 ounces where the mufflers only weigh 14 ounces total. So, if I went with mufflers, the airplane would be 2 pounds lighter overall.......... hmm... that is a big number! Maybe I'll run just mufflers on this.

Ok, now that the balsa has been protected with some clear sealer in the canister area I will mount the headers and cans 1 last time. Next will be installing the throttle servo and then the cowling, prop, spinner, ignition charge-jack.......... Then I think that is all.. How long will that take? Couple hours... lol
BH

[Jcarte]

The Red Aero 40% pilot and Extreme Flight intrument panel fit perfect in mine.

[capp1]

Bill, could you go with alum. headers to save some weight?

[psk560]

Bill,

Yes that is light. My 3W yak wings weigh slightly less than 4 lbs (3 lbs something) with 3 86111's and my QQ yak 120 wings weight 5 lbs each (ouch!!!) with 2 servos... Not sure on the exact weight on the 3W but I do remember it was less than 4 lbs... The QQ weight is correct but the plane is still a bunch of fun to fly!

Craig

[toc pilot]

Well, it seems like last night was my daugheters B-day party (I knew that!) and we did a movie night, pizza up till 2am with kids giggling and whispering while trying to go to sleep......... So, my plane is not done and here it is Sunday AM. Well, I am going to get on it right away after I pst some pix of what I got done last night before the kids arrived from all parts.

JCARTE: Pilots and panel looks GREAT!

CAPP1: Didnt really know which headers were going to work so I got thess (heavier stainless steel) KS headers to make sure I would have something that I could make fit. Now that everything is in place it is really easy to see the drop I need and the shape. I will make the swicth the aluminum ones as soon as they arrive.

PSK560: Wow, ok I guess I am good on the weight of the wings... now we'll have to see where my final weight ends up.. In the back of my mind I am yelling: THOSE CANISTER ARE ADDING 2 EXTRA POUNDS OF WEIGHT!!!!!

BH

[Flatlandman]

This plane looks awesome, the tail moment and the way you said it flys just makes me salivate for imac practice.

[ExtPlt]

Now that your done with the Yak,you need to get that Ultimat done.

[toc pilot]

Airplane is finished! I have just returned from TRCC where I test flew the 40% Yak, all went great! Just as I had hoped, the airplane flew straight as an arrow! Here are a few pictures of the assembled airplane befor the flight. I have a couple minor issues I need to fix, like shortening the headers, fixing the tailwheel.. The engine ran fine but the headers are too long and it will make better HP once I shorten them, I forgot to do this earlier and it was evidant that the power was down a little. Cant wait for more flights and some serious practice. Also need to get to work on some serious graphics..

No final weight yet as I only have a bathroom scale here at the house.

BH

[Flatlandman]

Will this one be an IMAC only plane or did you give it enough throw to tests its freestyle capabilities?

[ds1rc]

Looks great Bill.

Don S.