QQ 120 inch only took 1.5 years to build...

[psk560]

I thought I would share some pics of my newest bird... QQ 120 Yak 54. I bought this at Joe Nall from Wayne and it has been sitting for 1.5 years waiting for me to collect the parts and build the darn thing. (Why do arfs take so long to build? LOL)

The QQ kit. (12 year anniversary gift)
DA170, ks95's, 8 JR 8711 servos, about 44 pounds.

The 3W kit (10 year anniversary gift)
DA 150, ks95's, 14 8611 servos, about 42 pounds.
I've been flying the 3W yak built by Joe Cutright for about 2.5 years.

The QQ wings weigh 5lbs each. Ouch... (The 3w wings are slightly under 4 lbs I believe) I'm having a little trouble getting the QQ120 to stop during a one positive snap; I'm still playing with the trim and percentages though. The plane came out nose heavy and I've had to move the batteries back in the fuse and add tail-weight too, but the plane flies great and I'm enjoying it so far. Not sure how well it will hold together, but for about half the cost of the 3w kit it sure does fly great. The 170 is pulling it well with a 32-10 but I am in search of a better prop. Any thoughts????

Am I the only one who wishes the 3w kit was more reasonably priced...?
Craig

[Reza]

Hi Craig,

I would not use any cans on that plane. Because to me its dead weight without any power increase where tuned pipe will give you the power increase at almost same weight as cans. Just something for future if you decided to make it better.

Did you install two inboard servo for aileron? What size batts you have? I have almost same set up with RE3 and it weighs 42 lbs.

BTW, price is/was 1/3 of 3W. A friend of mine bought one shipped was over $6000. I too wish the price was half of that but it is very less likely for this to happen. Too many hands involved before we get a 3W plane considering 3W doesn't make them, they are resellers more than anything else!

[psk560]

Reza,

Thanks for posting. I thought about tuned pipes but didn't want to hassle with them... The ks95's (rear exit) work well and it has plenty of power on the up-lines with the 32-10. What prop are you using or do you recommend???

I put two servos on each wing. One on the outboard and one inboard (I did not use one in the middle). I'm using a weatronic receiver right now with 3800 mah duralite manganese packs. The weatronic reports 10.85 max amps and the voltage never dropped below 6.1 volts.

Craig

[Reza]

Hi Craig,

Move the outboard servo to middle, it will help with your snaps
I use AirModels 31x12, I have also flown 32x10, if noise is not an issue, try the AM 31x12, it will bring it even more alive! I use two 3000 LIMN. Your batteries are good

Pipe installation is not that difficult on this plane. If you ever decided to do it, let me know if I can help out.

Now that mine is dialed in, I really am enjoying it. I did an article on FG about RE3 and DA170 performance and actually was done on the same plane, when you get a chance, take a look at it and compare the performance to yours and see if it is worth the change or not. Plus it will help your CG as well.

Good luck buddy,
Reza

	Quote: Originally Posted by psk560
	Reza, Thanks for posting. I thought about tuned pipes but didn't want to hassle with them... The ks95's (rear exit) work well and it has plenty of power on the up-lines with the 32-10. What prop are you using or do you recommend??? I put two servos on each wing. One on the outboard and one inboard (I did not use one in the middle). I'm using a weatronic receiver right now with 3800 mah duralite manganese packs. The weatronic reports 10.85 max amps and the voltage never dropped below 6.1 volts. Craig

[Andy Thomas]

I will second the inboard servo installation. The ailerons on mine were extremely rigid. It did seem to help stop the snaps.

[psk560]

Heck, I'll move the servo inboard and give it a try. Let you know how it works out for me.

Thanks for the info. I'm also going to try a 30-12 and see how that works out.

Craig

[psk560]

Reza,

What is your servo setup? My rudder acts a bit weird at times and I'm wondering if I'm getting blow-back. I'm using 2 8711's on the rudder but I could add another without much fuss. Do you use 3?

Tons of fun to fly...

Craig

[mbacosa]

I have used the recommendations made by Reza and my Yak flies awesome. I dont 3D so two servos on the rudder seems adequet but if I were to 3D I would go with 3. I am using the two inboard servo mounts as well and my plane
snaps fine. I did have to dial up a little more aileron throw to help on vertical and 45 degree snaps and it has made all
the difference. I am running a DA 150 with Greves and I have plenty of power and my weight is just shy of 42 lbs. I am running a pretty simple set up with 3 A123 2300 mah batts, no regs, two receivers and fromeco switches. I can get four solid flights with 3-4 sequences per flight and still have 50% of the battery life left.....I have to agree with though. I thought the wings were a little heavy as well compared to some other models that I have had...BUT you will have a tough time finding a nicer flying plane....IMHO!!!

[Reza]

Hi Craig,

Nice pictures buddy
Can you explain weird? What does it do? BTW, I do have 3 rudder servo.

mbacosa,

I'm glad you are enjoying your plane. I am in the same boat, I really like my 120" Yak. I tend to baby sit it a lot more than my other planes

[psk560]

It wags a bit when I'm hitting the rudder hard in 3D flight and I notice a little wag in the tail at high speeds too. I haven't moved the aileron servo inboard yet but I do plan to do that. I'll try to get the horns glued in this week.

Craig

[Reza]

Yes, when you hit the rudder hard with descent speed, it may be giving you some blow backs. Also do you get slack in the cables from one side when rudder is deflected? If your geometry is correct, you should not get slack from either side when deflected!

[mbacosa]

I dont seem to have that problem at high speeds with the rudder. Seems very solid. I am running rubber coated kevlar cables and there is no slack when fully deflected. It seems to have plenty of rudder authority for Imac sequence flying.