Go Back  RCU Forums > RC Airplanes > 3D Flying!
Reload this Page >

Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Notices
3D Flying! Our 3D flying forum is the ultimate resource for 3D flyers. Also discuss the latest in "4D" flying!

Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Old 07-03-2006, 12:22 AM
  #451  
swasey1982
Member
 
Join Date: Sep 2005
Location: La CeibaAtlantida, HONDURAS
Posts: 74
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

thanks a bunch !!

Swasey
Old 07-12-2006, 08:45 AM
  #452  
gboulton
My Feedback: (15)
 
gboulton's Avatar
 
Join Date: May 2005
Location: La Vergne, TN
Posts: 3,743
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Well...

Hadn't commented in a while, thought I'd share some experiences at this point in the Yak's life.

Put its 35th flight on it yesterday (we'd be well beyond that, but had some engine issues that caused a month or so of not flying her), and here's some thoughts:

1) Ok...I've flown all 3 now. This plane with an OS 1.60, this plane with a BCMA SPE 40cc, and this plane with a DA-50. Hands down, the SPE 40 is the best of the lot. The 1.60, while it'll fly this plane quite well, and give you limited vertical, just doesn't QUITE have the oomph for true 3D flight. The DA-50, while certainly powerful enough to do anything you could ask, is simply too heavy. Sure, it'll let you balance the plane where GP suggests...but that is WAYYYY too far forward imo, as I've expressed before. By the time you get the CG back to where it needs to be (again, imo), there's simply so much dead weight that the plane doesn't fly light enough. Sure...it'll hover like a maniac, and pull out like a rocket...but the wings stall quickly, and rock badly in high alpha flight. The SPE 40 seems to be the best combination of all worlds. Yes, it has some negatives...not enough power to pull out of a hover for example (though it WILL hover the aircraft just fine). its light weight, however, allows the plane to be flown controlably at an absolute crawl, and inverted harriers act more like a kite than an airplane...steady as a rock.

2) As good as the hardware LOOKS in the plane, I've come across two concerns at this point. First, the tailwheel is, imo, garbage. (Of course, that was the one piece of hardware I wasn't real thrilled with originally, so it's no surprise). The big shock, to me at least, is the piano hinges. I was, frankly, pretty excited originally to see such "high quality, heavy duty" hardware in an ARF.

However, recently, BIG problems have developed. 3/4 Rudder hinges, and 2/3 right elevator hinges have BROKEN. They all failed the same way....the plastic broke away around the metal hinge pin. I've replaced the hinges in those surfaces with Radio South CA hinges (which have performed flawlessly to this point), and am keeping a close eye on the hinges in the other surfaces, expecting failure to occur before too long.

3) On the plus side, the gorgeous covering job has held up exceptionally well, requiring NO work with the heat gun or iron. It's stayed as nice as it was out of the box.

Couple of suggestions/tidbits picked up along the way:

As with lots of planes, sealing the control surface hinge lines makes a difference. In THIS plane it makes a BIG difference.

The cowl and canopy screws will be MUCH happier about maintaining their relationship with the plane if given some O-Rings.

Keep those pull-pull cables TIGHT. In relation to the size of the aircraft, this thing's got a pretty good size counterbalance on the rudder, and it likes to yank the rudder around. If you're seeing some tail wiggle coming out of turns, this is probably why.

-===================

All in all, now that I'm finally getting the little kinks/quirks of a new gas engine, and new engine/plane combination worked out, this plane is as enjoyable as I can immagine.
Old 07-12-2006, 09:28 AM
  #453  
marmitas
Senior Member
My Feedback: (1)
 
marmitas's Avatar
 
Join Date: Apr 2004
Location: Webster, NY
Posts: 146
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Thanks for the update!

With your current setup...do you know what your Yak weighs?
Old 07-12-2006, 10:53 AM
  #454  
gboulton
My Feedback: (15)
 
gboulton's Avatar
 
Join Date: May 2005
Location: La Vergne, TN
Posts: 3,743
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Current setup is as follows, marmitas:

BCMA SPE40cc Engine swinging a Menz 20x8 prop
6V 2700 maH NiMH Rx batt, 4.8v 2100 maH NiMH Ign. batt.
Hitec 645MG servos on Elevators, Ailerons, HiTec 5945MG Digital on the Rudder, JR ST-47 on the Throttle
JR R-700 Rx
CF Wing Tube to replace the stock Wing Tube

All up weight, dry, is 13 lbs 2 oz.
Old 07-13-2006, 09:58 PM
  #455  
Uncas
My Feedback: (1)
 
Join Date: Sep 2003
Location: St. Peters, MO,
Posts: 744
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

gboulton,

Nice post.

I am currently putting one of these together. I will definately install a better tail wheel. I am also going with a Brillelli 46 w/EI.

Just curious, where did you get your CF wing tube?
Old 07-14-2006, 07:05 AM
  #456  
gboulton
My Feedback: (15)
 
gboulton's Avatar
 
Join Date: May 2005
Location: La Vergne, TN
Posts: 3,743
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

I got it from the LHS, Uncas. Somewhere in this thread is the brand name and their phone number. They will take phone orders.
Old 07-16-2006, 09:26 PM
  #457  
water.boy
 
Join Date: Oct 2005
Location: Wichita, KS
Posts: 78
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

I have a buddy that I'm trying to deal with on his GP Yak. I've glanced at it but haven't looked very closely. I asked him what he powered it with and he said a First Place Engines 3.2. Here's the specs on the motor:

FPE 3.2 PHOTO 52. 3.6 lbs (58 oz) 22 x 10 Bolly 6700 23 Pounds Thrust ADD $579.95*

I don't know what servos are in it or if it's had any repairs. He builds a lot of planes so I don't think he'd skimp on the equipment. He's out of town right now so I'm trying to figure out what a fair offer would be. I'll start out with an almost insulting offer and work up from there. What do you guys think of the motor and the price?

Old 07-19-2006, 06:43 PM
  #458  
BMiracleTX
Member
 
Join Date: Mar 2004
Location: Abilene, TX
Posts: 63
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Hey guys....just got one of these GP yaks and a BT-43 EI.

Someone was saying that the gas engine is more fuel efficient and doesn't need the stock tank and suggested a 16 oz tank to lighten things up a bit. This my first gas engine/plane.

What do you all think?
Old 07-28-2006, 10:47 AM
  #459  
maxun
My Feedback: (12)
 
Join Date: Dec 2003
Location: canal winchester, OH
Posts: 523
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

my GP ultimate has a crrcpro45, the engine is good the muffler may crack, but is a dependable engine, it will hover my ultima but has poor vertical lift, now my total weith was 16.5, yes is heavy but man, I do harriers with no problem, for the price a crrcrpro is recomentded but a DA-50 will rock.
Old 07-28-2006, 05:02 PM
  #460  
Peter Burgess
Senior Member
 
Join Date: Dec 2002
Location: East Sussex, UNITED KINGDOM
Posts: 129
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Hi BMiracleTX,

A 16oz tank would be just right, I use one with a DA50 and usually only use 12oz for a 20 minute flight (plenty of low throttle usage)
Old 07-28-2006, 06:44 PM
  #461  
BMiracleTX
Member
 
Join Date: Mar 2004
Location: Abilene, TX
Posts: 63
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Thanks Peter! Off to the LHS to get a 16 oz tank!
Old 08-03-2006, 05:18 PM
  #462  
dunaman
Member
 
Join Date: Dec 2003
Location: Rio de JaneiroRJ, BRAZIL
Posts: 91
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

I did my first flights with my GP Yak 54 with an OS 160 FX, it was amazing and the engine is perfect for the plane specially for my type of flying that is IMAC style mixed with some 3D moves. I just have to put some weight on the front to achieve the balance I want. I am using a APC 18x6w and he flies very well.
Have anyone some suggestions about propellers to experiment?
Attached Thumbnails Click image for larger version

Name:	Pn38022.jpg
Views:	15
Size:	57.9 KB
ID:	501302  
Old 08-03-2006, 06:04 PM
  #463  
BMiracleTX
Member
 
Join Date: Mar 2004
Location: Abilene, TX
Posts: 63
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Without going to the more expensive props, try a ZingerPro.......I like these for mixed IMAC/3d.
Old 08-03-2006, 06:59 PM
  #464  
dunaman
Member
 
Join Date: Dec 2003
Location: Rio de JaneiroRJ, BRAZIL
Posts: 91
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Wich size?
Old 08-05-2006, 09:28 PM
  #465  
gboulton
My Feedback: (15)
 
gboulton's Avatar
 
Join Date: May 2005
Location: La Vergne, TN
Posts: 3,743
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

[]

Anyone need a pair of wings or a set of gear cheap?

Had a wing bolt either vibrate loose or fail in flight today...right wing pulled about 6" away from the fuse, and rotated. All but got the plane back...she came in on her gear, but hit HARD...broke her back back by the vertical stab, and whiplashed the motor into the dirt a bit, having broken the motor box.

The replacement is already in the shop though...LHS made me an offer I couldn't refuse on a GP 25% PW Extra...the SPE 40 oughta be a nice fit.

BTW, for what it's worth, I'm not kidding about the wings and gear. Wings are fine, no damage at all, and the gear are a brand new never opened set I WAS going to replace the originals with eventually. Anyone who wants to snag em cheap, fire me an e-mail.

Ah well...I've flown 3 planes this week: My scratch built Jim LeRoy Bulldog, a 1:1 scale DA-20 Katana, and the Yak...of the 3, I guess I planted the right one.
Old 08-06-2006, 09:24 PM
  #466  
jojobru
Junior Member
 
Join Date: Dec 2003
Location: Boca Raton , FL
Posts: 1
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Has anyone had problems with the landing gear. I had a landing today that was a little rough and opened the landing gear. It opened up enough to let the prop hit the ground. Are there any replacement carbon fiber or stronger aluminum landing gears on the market that will work well with the plane. If you please let me know.

By the way I am using a BME 50cc for power with a 3W 22-10 prop. The engine is still breaking in and show a lot of power.
Old 08-07-2006, 08:19 AM
  #467  
gboulton
My Feedback: (15)
 
gboulton's Avatar
 
Join Date: May 2005
Location: La Vergne, TN
Posts: 3,743
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

ORIGINAL: jojobru
Has anyone had problems with the landing gear.
Yep...that's why I had the extra set on hand that i mention in the post above yours.

They're fine unless you botch a landing...but they won't tollerate very much botching.
Old 08-07-2006, 01:08 PM
  #468  
AirTech
My Feedback: (18)
 
AirTech's Avatar
 
Join Date: Jan 2004
Location: Peru, IN
Posts: 748
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

gb,

I took a look at the Tower online catalog and was quite surprised with the replacement parts available for the Yak.

It seems Great Planes offers a replacement fuse for $124.99, but guess what; it doesn't come with the horizontal stab or the canopy assembly. The stab is not a problem since it's available for $58.99 but there is a major problem if you busted the canopy. Although the canopy is listed as "Great Planes Canopy/Frame YAK 54 1.60 ARF", the frame is not included [], which makes it useless. Also in case the wing tube is bent, the tube is not available. GP is not providing a comprehensive part replacement package for this ARF. I know most ARF vendors most time don't even supply a minimum of replacement parts, but GP seemed to be better in that area, and is very disappointing to find out about these issue.

ARFs provide the convenience of easy and fast assembly time, but when it comes to repairs they leave a lot to be desired. I am definitely sticking with kit planes or maybe a builder’s kit in the future. With a kit plane one always have the plans available in order to make new parts, and with most builders kit you can buy all the subassemblies separately.
Old 08-07-2006, 01:16 PM
  #469  
water.boy
 
Join Date: Oct 2005
Location: Wichita, KS
Posts: 78
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

gboulton, can you tell me how well the spe40 flew your plane before your accident? I have a Brillelli 40 that I originally bought for the CMP Giles 140, but I have a friend who has the Yak for sale. It seems like it might be marginal for 3D power...
Old 08-07-2006, 01:25 PM
  #470  
water.boy
 
Join Date: Oct 2005
Location: Wichita, KS
Posts: 78
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Nevermind gboulton, I just clicked back a page and answered my question It's too bad the 40 won't pull out of a hover better. I'm wondering if maybe a different size/brand prop would be better, like a Xoar. I really like this size of Yak, and if you think about it, Wild Hare's 80" Yak follows the same idea and here's what they say about it on wildharerc.com:

"The problem is, for really exciting 3D performance you need to be under 15 lbs. with an engine like a DA-50. So when we designed our new Yak 54, we made the wingspan 80” with a scale planform for plenty of wing area. Weight is between 13.5 and 15 pounds depending on the engine you choose.

This makes the plane a great sport flyer with anything from an OS 1.60 or Saito 1.80 on glow or a Brison 2.4 or similar gas engine. And with a DA-50 it is as hot it can get. Other possibilities are Moki/Mark 1.80 or 2.10, Saito 270/300 twin, Saito or OS radial engines, 3W28, Roto 35, Evolution 36, ZDZ-40 or 50, almost anything in that weight range will give excellent performance."

I'd like to get this Yak, but it seems that it's subject to the same tradeoffs in this size of airframe, nimble and light but no good 3D, or tons of power and it flies way heavier. I'll find a way to get there eventually
Old 08-07-2006, 02:42 PM
  #471  
gboulton
My Feedback: (15)
 
gboulton's Avatar
 
Join Date: May 2005
Location: La Vergne, TN
Posts: 3,743
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

AirTech,

As it was, I would only have needed canopy and cowl. Since I didn't "crash" it so much as perform a REALLY hard harrier landing, there was no real "impact damage" to anything...just stress damage from the landing. In fact (as I mentioned above) I'm selling the serviceable components (except the canopy...I have a plan for that *heh*) in the marketplace (I hope this is legal..if not, mods/admins please edit this post) over here : http://www.rcuniverse.com/market/item.cfm?itemID=213248

I certainly COULD have fixed it but...eh...time to move on. The Patty awaits building (though it'll get a different motor than the SPE-40 as it turns out), the motor and electronics all have homes planned for them...onward and upward we go.

water.boy : My BCMA SPE-40 flew the Yak quite well. Once broken in, it was certainly capable of hovering the plane, and lately the engine's come around enough that it WOULD pull out...it just did it in much the same way a snail might pull out of...well...anything. This was with a 20x8 Menz prop.

I'd tried NUMEROUS props on the plane, and had found that < 20" diameter wasn't enough, and anything 6" or less pitch was too slow for my tastes. I've got a couple of 20x7 Menz props on the way that i really expected would be PERFECT, and would give that extra couple hundred RPM to make her really shine, but alas...they didn't arive before the sad demise.
Old 08-07-2006, 05:29 PM
  #472  
AirTech
My Feedback: (18)
 
AirTech's Avatar
 
Join Date: Jan 2004
Location: Peru, IN
Posts: 748
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

gb,

Good luck with that Wagstaff. I have one with over 60 flights on it. Mine is powered with a ZDZ 40RV, and it has plenty of power for most anything. The one thing with the Wagstaff Extra is that at over 16lb. is a little high on the wing loading. It will stall at high alpha attitudes, so you must be careful. Otherwise a really sweet plane to fly, you will love it.
Old 08-08-2006, 08:04 AM
  #473  
jonkoppisch
My Feedback: (162)
 
jonkoppisch's Avatar
 
Join Date: Dec 2001
Location: Mobile, AL
Posts: 2,942
Likes: 0
Received 2 Likes on 2 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Does anyone know where to get the al wing tube replacement other than the CF? Very disapointed in great planes on this one []
Old 08-08-2006, 08:45 AM
  #474  
gboulton
My Feedback: (15)
 
gboulton's Avatar
 
Join Date: May 2005
Location: La Vergne, TN
Posts: 3,743
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Jon,

I found mine. It's the original one that came with my Yak. I replaced it with the CF tube fairly early on, so it's in brand new condition.

Since GP doesn't appear to offer one, I looked up the closest thing I could fine at Tower, which is the replacement tube for 1/4 scale Patty Wagstaff Extra, listed here : http://www2.towerhobbies.com/cgi-bin...&I=LXESA2&P=ML They are (much to my happiness) the same diameter, so it's probably a "fair comparison".

However, at only $11, I don't think I'll squeeze you for a "fair price". Shoot me an e-mail so we can arrange shipping, and if you'll pay shipping costs, you can have it.
Old 08-08-2006, 09:40 AM
  #475  
jonkoppisch
My Feedback: (162)
 
jonkoppisch's Avatar
 
Join Date: Dec 2001
Location: Mobile, AL
Posts: 2,942
Likes: 0
Received 2 Likes on 2 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Thanks

Email sent

Thread Tools
Search this Thread

Contact Us - Manage Preferences - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.