depfife

My Feedback: (14)

Finally got my 47" Yak in the air today. It's a keeper! The only thing close to a problem was the throttle servo mount was on the wrong side, but that was a five minute fix, so no complaints. With the servos in the tail I was little concerned that the light Webra 50 would not allow me to get the CG right but there was plenty of room on the engine mount to move it forward enough.

The hardware that comes with the kit is good. OMP gets bonus points for including Tetherite landing gear. The only things I did not use were the hinges and fuel tank. Nothing wrong with what came with the plane, but I have a bunch of Radio South hinges and I have had good luck with them. I used a Hayes tank because I am lazy and hate to plumb a tank that requires bending tubes. Plus I had an 8oz Hayes tank that came off another plane that was ready to go.

The first flights were uneventful, and that's a positive thing. None of that awkward feeling that sometimes comes with a new plane. I'm going to add a washer to bring the engine over more to the right as it is pulling a little to the left in a hover. I'm heading back to the field with it as soon as I get home from work tomorrow.

Now that I have some room on my building table I can start on its big brother the 65" Yak. That big box with a new YS 1.10 sitting on top of it has been screaming "Build Me!"

AFSalmon

My Feedback: (3)

Yep, that baby Yak needs a big brother. Hey save that tank for the next profile though. I really like the molded in grooves for the tie straps. Nice touch.

depfife

My Feedback: (14)

Got the washer added and got to the field late this afternoon. Everything seems to be trimmed out nice now. The Yak is a little bit looser than my Burritos, but not squirrelly at all. I am by no definition a 3D expert, but I am becoming comfortable with the Yak quicker than any other plane I have owned. I was doing tail touches this afternoon - and for me that is no small feat.

I put some 2 1/2" wheels on it today. Our grass field is fairly smooth, but not golf course smooth. The stock 1 3/4" were working, but I think the larger ones are better on our field. I'm glad the days are long, so I can fly after work. This plane will will induce a desire to burn a day or two of vacation to get to the field.

You can see in the photo how far I had to move the engine forward to get the CG set.

STLPilot

My Feedback: (21)

Good stuff Dep ... keep going ... your reports will bring more smiles as you fly it.

gaspasser

My Feedback: (9)

I will complete my Yak 47" today . I'm pretty good at 3D and this plane will fill the ticket . Some complaints . First ,It was next to impossible to thred the rudder and elevator servo wires thru the fuse . The hole on the back of the wing could be larger . 2nd The instructions are vague .If I hadn't built a few of these things I would have had a PROBLEM! 3rd None of the screws,nuts and bolts fit properly for the mounting of the landing gear . I had to use my own .I also had to use my own stuff to mount the engine .All in all ,if you are experienced in building ARF aircraft and if you have time ,buy this plane.I forgot .The way the fuel lines are fed from the tank to the motor are ?????.There's no holes in the fuse for that or the gas tank that I could find .

depfife

My Feedback: (14)

Not having holes for the fuel lines is common for short nosed profiles. You can run them over the fuse, behind the engine, or drill a hole.

AFSalmon

My Feedback: (3)

Don't know if you tried to feed the wires through the fuse by pushing them but that would never work. I use a nylon pushrod like the yellow ones from the LHS and tape the servo wires onto one end so that the connectors are staggered and the tape provides a smooth transition to prevent conectors from snagging. Then I feed that nyrod through the fuse and out the wing and pull the wires on through. Never had a problem ever doing it this way.

depfife

My Feedback: (14)

In the past I tied a string to a small nut then dropped the nut through the fuse. Then I would tie the string to the servo wires to pull them through. With the 47" Yak I used the nylon pushrod like Mike suggested. The nyrod was much easier and quicker than the nut and string.

Spacey

A nyrod ey? That would be a little easier indeed! Great tip!

AFSalmon

My Feedback: (3)

I thought I put that tip in all the manuals? Might have left it out of the arf manual though.

depfife

My Feedback: (14)

I don't have the manual in front of me, but I'm pretty sure the nyrod tip is in there.

Spacey

Just shows it helps to sometimes read them manuals doesn't it?

zetor

My Feedback: (2)

I built one of these. Waterfalls were really tight but it had a wicked belly tuck in knife edge.

AFSalmon

My Feedback: (3)

Then you probably have either your cg off or your engine thrustline off. The Yak properly set up has virtually no coupling.

zetor

My Feedback: (2)

CG was per instructions. The thrust line is paralell with the fuse laterally. Will adding right or decreasing right thrust fix the problem? A fellow by the the name of Gator on the other site had the same experience as mine. I may be un-intentionally exaggerating with the "wicked" adjective as the only other .40 size plane I can compare it to is the EF edge, which as I understand is a pretty tough act to follow in the KE department.

AFSalmon

My Feedback: (3)

Gator is the man, don't mess with him as I here he is one huge buff body building maniac! Pretty much every incidence, design criteria, and engine thrustline will affect coupling in my experience. Just sounded like when you said "wicked" something was way off. I can KE both my Edge and Yak straight down the runway as low as I want with minimal inputs. There is always some corrections to be made based on wind and the fact these are very short coupled funfly planes but again very minimal.

Spacey

zetor: Something is definitely off. Maybe get your CG so the plane holds level flight upright or inverted with zero elevator input. Then also get the engine thrust so the model needs no rudder "trim" when hovering. That should give you a fairly good in the ballpark setting for knife edge. I know the little Yak can get full of funny coupling if you slam the rudder in too hard as you enter the knife edge but that is very simply because of the amount of rudder authority it has so if you change the respective speeds of the left and right wing too dramatically too quickly you are going to see some funny things happening (At least that is what my pink stuff figured just now...it's early in the morning so bare with me ). But other than that mine will knife edge with the best of them with equal ease. Check into it again and let us know how it goes.

dbruening80

My Feedback: (1)

Hey! It's not impossible to push the wires up throught the fuse, Ive had to do it twice! And let me tell you, my fiance' really enjoyed helping me too Guess I "skimmed over" the directions for radio instal a little too quickly, didnt even see the nyrod tip.

AFSalmon

My Feedback: (3)

hey something else I forgot to mention that affects pitch moments is the nuetral position of the ailerons. This is a very common thing that is overlooked when folks set up new planes and most (including me) just kind of eyeball the aileron nuetral position. If they are deflected up (spoileron) or down (flaps) then that will affect how the a/c pushes or pulls during KE.

Spacey

Mike I agree on the whole aileron thing. I always TLAR this one but do you know of any method to accurately check this? I've been trying to come up with one for years but there is really nothing I can think of that will accurately tell you if their up or down?

AFSalmon

My Feedback: (3)

I lay a straight edge along the tip centered from the leading edge to the hinge line and then fine tune the aileron center with the sub trim on the tx. Of course as always you should try to get the geometry of the linkage system as close to ideal position as you can first.