rmh

Angus - the "Jack the Giant killer " is not with this plane -It is another, larger light model with the 80
This on onZDZ50 and KS pipe is already extremely strong -best on 22x8 Mejzlic turning fast (7700)
very quick power up on hovers /etc..
This type setup was good on small glow engines on profile 3D thingies and works well here.
18-20 lbs on piped 80 will give similar performance.
Neither setup is any good at full throttle level or diving as engine overspeeds (as does plane)

pequeajim

My Feedback: (1)

Yes, I am, I think they are great too. Very cool solution.

jrjohn

My Feedback: (24)

remember to sand the neck down so it can sandwitch tightly. aprox. 195 thousands thickness seems to be the charm.

John

jrjohn

My Feedback: (24)

I was wondering who is going to be the first person to build scale looking wheel pants for this plane.

take a look at the pics in this link

http://www.yakuk.com/yak54pics.asp

rmh

I did those type pants for my EMC2 pattern plane 9 years ago -- All I got were blank looks and questions
Note the green and red trim on white one in center of grouping - This is what I used as basis for my YAK scheme-only I doubled & flipped the wing trim forward
I was puzzled when I saw the full pants on the EF Yak --
Mine are on the shelf -nice pants --they go on another design now

jrjohn

My Feedback: (24)

Dick, I agree that you would get a lot of blank looks and questions from the flatlanders not to mention people might start talking about you

but a wise old man once told me, "if people are talking about you, you know their thinking about you"

I like the Russian wheel pants, I think I may cannabalize one of my old pair and try to make a scale looking pant.


john

Maudib

My Feedback: (51)

Well, after a VERY long and trying wait, I was able to go to the field and fly my 87" Yak.

Weather was perfect! Temps mid-high sixties, mild winds maybe gusting to 5 mph.

I balanced mine about 3/4" back from the yellow stripe and figured it oughta fly there.

And fly it did! As I had been anxiously hoping, the 87" has all the capabilities of it's smaller brother. I was SO impressed with how the plane flew.

I got 3 good flights on her, so no real opportunity to tweak the throws, but ALL the surfaces at max throw are amazing. Knife Edge back and forth all day long on rudder that will pinwheel turn the plane. Ever so slight rudder coupling on medium rates and a noticable tuck to the gear at max rates.

Elevators will flip, waterfall, wall, etc like MAD. NO snapping tendencies at ALL. Wingtip spins are beautiful and just like previous reports.... snap rolls stop when you do like instant.

Mine's at 15.5 lbs without the pants. I used the 23x8 NX prop and though it was adequate, it was working the engine too hard. 6200 (same as I got back when I did my earlier tests in the first part of March. So I should get the 6800-6900 I saw on a 22x8. Seems the right prop for me anyway. I have an MSC but the root is so wide it won't fit the spinner cutout, and I don't want to widen it out more, so I might try a Menz-S 22x8.

Everyone at the field was very impressed with it's capabilites... it does make you look good.

At the CG I stated, inverted flight was hands off... it may be climbing ever so slightly so if I put the pants on it should adjust it JUST right for me... maybe 1/2" or so behind the yellow stripe. This thing locks into a hover and only needs breaths of stick input to lock it there.

It really DOES fly like a foamy (all the good traits) with the stability of a 33%'er. I'm sire higher winds will buffet it around more, but it's worth the other traits.

Only two clicks of right aileron were needed with all the surfaces set neutral to their "parent".

The DA started and ran like a champ... it does exhibit the drop in rpms thing that the new carb block fixes, but it's just an annoyance til I order another one. I'll take the new one and put it in the Yak, then send this one in for the fixes.

WoW, WoW, Wow. I can't wait til next time! THis is going to be one awesome plane to trim and tweak to perfection.

I've never been so proud of an ARF... her's a pick of a rather bald, thinner dude next to my newest baby!

SPACE SCOOTER

It looks like this thread is for the few fortunate folks who have recieved this aircraft. How stinking long does a person have to wait?!? I've tried to email this EF company several times without any feedback what so ever. The person who Posted #4875 simply wanted to know if anyone might know(or know someone who might know)when the next shipment of Yaks is due to arrive..It's very frustrating when you feel like you're getting the run around..DOES ANYONE KNOW ANYTHING ABOUT THE NEXT SHIPMENT OF THESE YAKS, OR SHOULD WE JUST GIVE UP AND MOVE ON?? Thanks to anyone who can help.

CHassan

My Feedback: (13)

Excellent Dave, you deserve what you got I guess

Just like Dave I got mine to the field today. Not as much luck as Dave though.
First flight take off was a non-event. 3 clicks up ele and one or two click left ail. Circled around a bit to get use to it and noted the engine would spit and sputter pretty bad. Tried knife edge and inverted, a couple rolls and a loop or two and the engine quit. dead stick landing, another non-event.
Second flight, take off again a non-event. This plane does like to fly, gets up quick at 1/2 throttle. I did some more slow flight and some faster rolls (still low rates) tried a flat spin or two and kept adding way to much throws. went to try an inverted flat and heard a gut twisting sound, everyone started yelling something came off, at the same time I noticed it wanting to roll real bad.[:@] Brought it down for a fairly uneventfull landing, thats when I noticed the entire blue section on the right wing was hanging on by the covering trapped in the fuse.
Looking closer it looks like there was still alot of sanding dust on the wing when it was covered. The yellow stripe stayed on but the blue pulled from under it and somehow got cut by the prop and a little piece floated down to somewhere near Cincinatti. I had gone over the wing at least twice with my covering iron.

I had thought my balance was pretty close to the yellow strip but at the field before my second flight we checked and it was close to 1 1/2" behind the stripe. inverted flight actually required UP elevator to keep it level. Knife Edge also required alot of up to keep straight.
My guess is my Ail might be reflexed somewhat, They looked good but so did my balance here at home.
I'll have to recover and rebalanbe the plane before i try agian.

All in all I think this plane will be awsome once I get it set up. On a 22x10 vertical was never ending, I didn't try any hovering or harriers or anything due to the short second flight, but as slow as this thing gets before it dropped a wing, I forsee no problems.

Just a reminder thought, check double check and continue to check that the seams on the LE are not coming loose!!!!!

My buddy did get some video, If I can get him to get me a copy I'll see if I can post the part where the covering came off.

CHassan

My Feedback: (13)

SPACE SCOOTER



I think at last call it was sometime in June.

SPACE SCOOTER

Thank you very much.....Don't mean to sound rude, but all of this reading of others enjoying there yak is more than I can take!!!

chipwill

My Feedback: (12)

Good to have you back flying Maudib!

I had to resist flying the Yak for two days while I tweaked my backup plane but now it is going to be practice practice practice for next weeks IMAC.

I cant wait to fly mine again!

Chip

basmntdweller

My Feedback: (9)

My switches are the heavy duty Futabas which only switch the positive wire. The negative does carry on through so there would be a common junction in the RX with both plugged in. I thought that might be what was happening but was curious if anyone else had ran across this situation before.
Thanks,,,Matt

jrjohn

My Feedback: (24)

David, Your looking strong, Glad to see you Yak flys like all the rest.

I'm running a 23x8 NX prop. it's turning 6380 I thought it performed really well and I didn't think it was laboring. You think it's too much prop?

John

Fastlif

My Feedback: (2)

space scooter,
Yeah I feel your pain, I am in the same boat. I did order one the a few days ago, and Chris said he hopes by end of June, but was not sure, said he is waiting on word of next shipment ready by his kids in China. I just wish he kept a more up to date website with info, he could answer alot of questions right there on that and save people from getting torqued and buying something else. His web still has stuff from last winter on it????

Maudib

My Feedback: (51)

Space Scooter,

you did come across pretty harsh, but truthfully I can understand.

Realize that the guys who have these planes from the first batch (most of them anyway) have been waiting 2 years or so. NOT that you will have to wait that long, but because the first design was with another manufacturer that basically screwed the owner and built some real bad stuff. Chris refused them and made us wait... BOY am I glad he did.

There were some minor issues with this first batch too, but nothing a fella can't follow this thread deal with. Most likely the second batch will have some of these issues already addressed.

A designer/developer like Chris is at the mercy of a second party... the manufacturer. In this case he was the first to locate and begin using his current manufacturer... whom I'd call the best in China at this point...perhaps the best builders outside of custom guys here in the U.S.

BUT... word gets out and a smart manufacturer would market themselves... making their production line even more challeneged. They are growing to meet the demands, but it is sometimes a learning process and meeting promised deadlines sometimes just doesn't happen.

So Chris waits... he could easily sell 1,000 planes as fast as he can get them. Believe me... don't you think he'd have them here already if he could?

So to make a long story short... This plane is worth the wait. PERIOD. I've not seen the other Yak offerings but I'd have to seriously doubt they'll come in and balance at they weight the EF does. The only exception might be the new BME Aircraft Yak.

As CHassan stated... the last word is June... and I hope for everyone's sake including Chris' that they come in then. This is the baddest plane I've ever owned and I called Chris and got on the second list the moment the first one arrived.

This is a plane I WON'T be without... so hang in there if you can, try the BME if you can't, and stay away from TOC1 or the rejects still being peddled by a few unscrupulous dealers. I see that J Avant is selling his (can't imagine why) but it's here:

http://www.rcuniverse.com/market/item.cfm?itemId=98773

Maudib

My Feedback: (51)

CHassan,

Sorry to hear about the covering thing....

You know... I never touched mine with an iron... really. Heat gun on the tail when aligning the stab to the wing... but that's all.

I will go over it with an iron though (usually do, but the day was here and time was short)... I haven't even sealed my surfaced yet either... that'll be done before next flying day. No hint of flutter and the surfaces as mentioned before were simply very effective. Still sealing hinges is a must IMHO.

The covering is UltraCote so fear not the hot iron... just don't get so hot and stay in one place to shrink the striping away.

Tweak that motor better. There is no reason any gas engine should quit in the air if it's running properly on the ground. Don't put it in the air again until you work the low and high needle.

Set the low end at the factory position and then lean in 1/8" turns until your transition is smooth... when it starts to "cut" on transition drop it back. Then lean the high end for maxrpm' and then rop it back a 1/16" turn. If you have ANY hesitation in throttle response, any missing or a bad idle... go back and repeat the process til it's all gone.

If after a while you can't get it just right... begin to suspect an ignition problem.

I've seen guys try and tweak a plane then fly it... only to watch a great plane bite the dust due to dieing at an inopportune time.

Along that same lines, I tweaked my needles with the cowl on... decided at last minute to out a small hole in the cowl for needle access (works for the DA anyway). Will put a grommet in there to "finish" the look.

-J. David

Maudib

My Feedback: (51)

6380 is a little low (and my 6200 is way too low). The DA is a horse, but we both are loading the engine too much. DA would probably agree. The issue is more heat than anything else.

Here in Ohio, I've been very well impressed with the MSC 22x8 on the DA-50... 7000-7100 for Tom on a new engine with stock muffler and he has noticably more power on the uplines on his 1 lb heavier plane... he has quicker response as well in the throttle. Many state the 23x8 moving up to 24x8 is the ticket for them. And whatever works for them is great. I'm going to remove the spinner cone and fly an MSC 22x8 for the next few flights to see the rpm/flight performance difference.

Will let ya know how I fare...

CHassan

My Feedback: (13)

The only thing is I think the BME Yak is not due until June also. I've had a problem with mine, but I wouldn't trade it for another Yak if I could. My first flight ended in a deadstick and the glide ratio reminded me of my aspire glider

CHassan

My Feedback: (13)

Dave, I did lean out the engine about an 1/8 turn on the low end for the second flight. It cleaned it up quite abit. I think the engine quit pulling from a down line on my first flight. I had very little fueleft actually (15 min went by real quick!!). I don't think there is a problem other than tweaking the engine.
I will get a new batt for my tac next time I get it out and see what I get with the 22x10. I don't know what it was turning but even sputtering it pulled the plane like crazy

Also did you get my request for graphics? Just wondering I know I typed it out but couldn't remeber sending it

rmh

I don't run a DA- but props are props -and they are what get the job done -
So far --on my YAK- the 3D is best with the fastest turning 22x8 --which is the Mejzlic.
The bigger 22x8 - MenzS -or a 23x8 -all work super --untill you load the model-such as crawling along at very high AOA--or are doing a torque roll sliding down.
You guys might just try propping with 22x8 Mejzlic to see difference.
Our model has full pipe system so natcherly we get more power than in cowl muffs.
I would guess that on DA factory muffler on this prop -you will spin close to 7000 give or take a few .

bodywerks

My Feedback: (4)

I had an MSC 22X8 that I got 6700 max and just under 21 lbs of static thrust(remember my altitude) but it splintered when my gear broke. The only other prop I could find was a BME 22X8 and I got 7100 out of it and over 21 pounds of thrust.

matus777

860 ft msl...62 deg F...Menz 22x8 wooden ( with std in cowl DA muff) 7150 to 7200 rpm, cooled down and same thing on Mez 23X8 C/F 6500 rpm......I like the 22X8 better and the plane actually flew differently on each prop. Still breaking in on 32:1.

I've had other issues but my early initial impression was that i had two different planes when each prop was installed but not the right conditions to really confirm it. Yesterday I had a guy fly my Yak (he has one too but with a pipe) and we did a prop switch on mine and he was amazed at how different the plane flew.

I must say that each prop had strong points for the plane and some CG issues might be involved too but if you want two Yaks just get two different props!!!!!!! Seriously...you might be surprised with the differences?

rmh

Yes - we easily noted difference-switching from the 22x8 MenzS type to 22x8 Mejzlic .
Once in motion -- the differences are much less noticable
The 23x8 actually has more top speed -speed takes less power than hovering .

We are propping for a minumum of 7200 rpm static on biggest props.
So static rpms run from 7200 upward--
Propped into the low 6000 range - the engine still works but power is way off.
I did not even bother with this setup -having been there before
This may sound strange but you can't ignore the results.
At 4350 ft - the engines put out less - the prop has to spin faster to get same thrust-the plane has less lift so all in all we have to go with all the power we can get -just to equal a "avg" setup at sea level.
On our electrics - we get a break as the power is same anywhere -that leaves just lift and thrust differences to deal with.
A bigger prop and lighter all up weight puts it straight.

jeang

Well I finally got around to maiden my yak,all I can say is WOW!! Just like the 68"Yak Awesome flying planes.
The wind was blowing pretty hard,maybe to much to maiden a plane but I had to fly this thing.This yak can fly so slow that it would make a trainer plane jealous.Its like Wayne said "A 30% foamy" My CG is 1/2" behind the yellow stripe and I plan on moving it forward a bit so I dont have to force her down as much during landings.
My Yak weight came at a bit less then 15.5 pound,Im using 3 2300 NMH packs and 3 super switch,also no pants and using 5" wheels.I could ezlly bring the weight down by removing 1 pack & switch and going to lighter wheels but I dont c a reason to do so.

Im running the stock DA muffler turning a MSC 22x8 @ 7100. It seams to have tons of power.The DA runs really well and I haven't touch the needle,the factory setting seam to be about right for my area.(1175 feet)


Im One happy Yaker


Jeang