NEW Extreme Flight RC Yak 54, 74 Inch!

[Ian]

Howdy everyone!

Thought id try a build thread on here......


As you all know, the extreme flight RC Yak 54 was quite frankly, well, an epic plane. Set the example for all things to come in the 3D world, in both quality and performance. However, with one thing or another, manufacuring ceased.... to the annoyance of many people!

Not to be set back, Chris has designed somthing a bit bigger, and much better!!! The EFRC Yak 54, 74" span!

and i have one





Well, the model was originally flown on an OS 160, which is what you see in the pics (chris putting it through its paces). Dan of Freestyle RC is also using an OS 160. It can also be used with an YS 140 and the 160, which i can tell you all is one heck of a motor (turns an 19x8w, and ooh so smooth).

However, ive gone for somthing slightly more enviromentally friendly Hacker Power!



To be a bit more specific im going to be using a Hacker C50-14xl Acro Competition. This is a top of the range motor, best money can buy, for 2m models, all the top pattern pilots use it. It comes at price, but when added up against a YS 160/hyde/haitori setup, its about the same. with 10s1p Flightpower 5000 packs, and a 21x13 Wide Electric prop, i should be pushing 2.8Kw!!! hopefully all that power will be helpfull as an E setup will weigh approx 1kg more than the IC setup (dry), about 2lbs. If i can keep the weight to 12lbs, and have 2.8kw, i will have 233w/lb!

As for small gassers, personally i wouldnt reccomend one, but if i did have to, a ZDZ 40 or a Evo/MVVS 45 MAG (magnesium casing, much lighter), both with lipos on the ignition

unlike many (read: 99% of them) companies, Chris has listened to peoples comments on the 68" yak, and changed things for the better on the 74. For example...... a pre-isntalled canopy latch!



a strong, light Carbon Fibre tail wheel (stearable, just in this picture its not had its arm attached). Red screws are my own fittings, as i had them and they look cool



Other things include the double truss phelonic controll horns, which will have heavy duty 4-40 dubro pushrods attached



and again, this is another CAD masterpeice, first time these pics have been shown on the net!

and check it, NO FOAM!

[Ian]

now the fun bit!!

what we have here is a:

Hacker C50-14xl Acro Competition (with my name laster engraved on the back)

Hacker Master 90-0-Acro Competiton ESC (posh F3A brake on it)
Programmer Box
APC 21x13 wide electric which has a chord of nearly 2" near the centre!


Its absolutly amazing, superbly engineered bit of kit, and im glad, the price was stupid!!! Its the best motor setup money can buy, so hopefully it will go well

sorry for the fuzzy pictures in the next bit, my cameras macro setting wasnt working for some reason





prop put on canopy opening for sizing, its huge!




installed the ESC. mounted under the motorbox, plenty of air should flow through the cowl and then over the ESCs huuuge heatsink and then out of the bottom of the cowl. Alse opened the front of the first "firewall" to let air in for the batteries. I will most proberbly open the rest up too and create some baffling to cool the lipos. Using 6mm gold connectors

again, sorry for the fuzzy pic




Now the only problem with the hacker C50 range, is mounting the thing! The motor is designed for a pattern plane, where it can be mounted on nose ring of the fuse, however, as i have a huge open cowl, i cant do this. So i CAD drew a motor mount. The final design has changed a bit now, but this is what its vaugly like....





Anyway, thats what ive done now, keep checking back for more updates, i plan to fly it next week so there will be a few comming

Thanks for looking
Ian

[50%plane]

Looks fabulous Ian!

[HuckinChikn]

Ian, I definately want some progress reports! the thing looks amazing!

[Ian]

Another pic to wind you all up, this ones got an OS160 in it. Pic taken on its first flight.

[50%plane]

*drool*

[Uncle Brett]

Nice Ian, can't wait for the rest of this build and the flight report. I'm thinking of doing the same build except going with Neumotor power instead of Hacker. I don't know if you know this but Esprit Model (www.espritmodel.com) sells an aluminum motor mount made just for the Hacker C50 series, if you don't want to make your own. If you're interested go to the website, click on Accessories/Motor Accessories/Motor E Mounts. It's type 3 motor mount. You just have to figure out how long you need the extension rods.
Thanks again Ian, I will be following this thread with great interest
dook

[youngflyer]

how did you do that hatch. where did you buy the clip from!

[Ian]

it comes pre-installed. great idea, especially when i have packs to remove, will take all of a second

[Ian]

on with the build!

ive now installed the rudder closed loop, i used the durbo 4-40 system as i didnt get one in my kit (pre-production plane remember). Servo is a hitec HS5645, a bit slow, but im only borrowing it and ill get my own one soon.



down the fuz, i have crossed the wires over so i dont get slack in the non pulling wire



and at the back, i have 4-40 dubro racing mega ball links. Very high quality these.




next i glued the cowl mounting blocks in with thin CA. sorry for the fuzzy pic



i then installed the firewall tri-stock. this is all pre-cut and pre-chamfered. Very nice touch



next, link up and hinge the ailerons.

Started with making the bottom of the phelonic (Sp.) control horns rougher by rubbing them down with a low grit sandpaper.



them i dry installed them, drew around them, and cut the covering away for a good glue joint, using a soldering iron to make sure i didnt weeken the wood



and then glued in with 5 min epoxy...

[Ian]

and just to tempt you all a bit more, heres a pic of the inside of the wing! very complex!

[GremlinX]

Man.... I just sold my ready to run 68" EF with a Saito 1.80 to make room for one of these...