Go Back  RCU Forums > RC Airplanes > 3D Flying!
 Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine >

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 02-18-2007, 09:31 PM
  #601  
Senior Member
 
Join Date: Jan 2004
Location: Cypress, TX
Posts: 172
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Here is a picture of my setup. I usually try to keep things simple. I close the choke plate with my finger on the plate and open it with my finger on the lever. I really like this engine/plane combo.
Attached Thumbnails Click image for larger version

Name:	Bz79000.jpg
Views:	23
Size:	120.7 KB
ID:	624563  
Old 02-19-2007, 05:54 PM
  #602  
Member
 
Join Date: Jan 2007
Location: Regina, SK, CANADA
Posts: 38
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

FLylow, thanks for taking the time to take the pictures and post them, they have really helped. Did you use the stock muffler? I am planning on using a Pitts style muffler from Bisson. Did you mount the rudder servos in the tail, or did you use a pull-pull? How did the CG work out for you? I would be very interested and greatfull to see you set-up. Again thanks for your help.
Old 02-19-2007, 07:47 PM
  #603  
Senior Member
 
Tesla1856's Avatar
 
Join Date: Jul 2004
Location: San Antonio, TX
Posts: 257
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Fingers,

Thanks. Yes ... with this being my first giant scale gasser your posts are a big help.

I see what you mean about the weights. It seems to me that it would be better to just tell us the total weight of the engine (with the plug, EI box, prop. hub, etc.) as it's all needed in the plane to make it run. Then, tell us the weight of the muffler separate because some will use it and some will go after-market.

Looks like the Fuji-43EI is coming with a steel muffler now (although it is silver in color). Unfortunately, I can't find the actual weight of it on Tower or the Fuji .pdf owners manual. No biggie though because with the additional cost of a aftermarket rear-dump Pitts, I'm going to stick with the stock one.

I'm going to order my Fuji 43ei or the 50ei in a month or so ... so I still have a little time to decide which one.

ORIGINAL: fingers73

The Fuji specs are funny, the 50 is weighed with a steel muffler the 43 has an aluminum one.
Old 02-19-2007, 08:25 PM
  #604  
Senior Member
 
Tesla1856's Avatar
 
Join Date: Jul 2004
Location: San Antonio, TX
Posts: 257
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Well I got my ailerons installed the other day (first time installing hinge points) and my Hitec HS-5645MG aileron servos should be here by the end of the week.

So with a Fuji Electronic Ignition engine, do I need this Kill Switch:

[link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXJ776&P=ML]http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXJ776&P=ML[/link]

A 4.8v 1500 mAh NiMH for the ignition module AND a 6.0v 2000 mAh NiMH for the PCM radio system and servos.
... so 2 of these so I can turn them off and charge those batteries:

[link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXPNU2&P=7]http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXPNU2&P=7[/link]

So, a minimum of 3 switches on the outside of the plane? Is that right?
Old 02-19-2007, 10:27 PM
  #605  
Senior Member
 
Join Date: Jan 2004
Location: Cypress, TX
Posts: 172
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Kfoster,
I did use the stock muffler. My rudder servo is in the tail (one Hi Tec 5955). The throttle servo is mounted next to the area where a pull-pull servo would be mounted. Two 1650 mah nimh batteries are mounted just in front of the wing tube. The receiver is located just behind the wing tube. A 1500 mah nicad is mounted inside the engine box. Balance is 1/2" behind the maximum Great Planes recommends.
Old 02-19-2007, 10:38 PM
  #606  
Senior Member
 
Join Date: Jan 2004
Location: Cypress, TX
Posts: 172
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Tesla1856,
I bought the same switch you are considering for the ignition cutoff. Don't make the same mistake - it's for non electronic ignition (magneto) engines. I used a receiver battery switch for the ignition kill. Just put it between the ignition and battery. Works great. Consider a second way to kill the engine from your radio - just an extra measure of safety. The other switch made by EMS could work for each of your batteries (three switches).
Old 02-20-2007, 01:11 AM
  #607  
Senior Member
 
Tesla1856's Avatar
 
Join Date: Jul 2004
Location: San Antonio, TX
Posts: 257
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

For the radio system I was planning on running only one 2000 mAh NiMH. Is that going to be fine for 3x15 minute flights = 45 minutes or should I be thinking about running two batts. like you are?

ORIGINAL: Flylow

Two 1650 mah nimh batteries are mounted just in front of the wing tube.
Old 02-20-2007, 02:27 AM
  #608  
Senior Member
 
Tesla1856's Avatar
 
Join Date: Jul 2004
Location: San Antonio, TX
Posts: 257
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Flylow,

ORIGINAL: Flylow

I bought the same switch you are considering for the ignition cutoff. Don't make the same mistake - it's for non electronic ignition (magneto) engines. I used a receiver battery switch for the ignition kill. Just put it between the ignition and battery. Works great. Consider a second way to kill the engine from your radio - just an extra measure of safety. The other switch made by EMS could work for each of your batteries (three switches).
Thanks. So you just cut power to the electronic ignition module with a switch to stop the engine. While it's off, you can use the charging jack to charge or check voltage on the ignition battery.

For the radio remote cut-off (I think I should probably use one), should I use this ... or do you recommend a different/better one?

[link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXCJD6&P=]http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXCJD6&P=[/link]

I would rather use an solid-state switch anyway. Plus, the opto-isolated design should help with the engine ignition/ receiver radio interference I keep hearing about.
Old 02-20-2007, 02:28 PM
  #609  
My Feedback: (2)
 
fingers73's Avatar
 
Join Date: Mar 2005
Location: Kent City, MI
Posts: 69
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Tesla,
I'm glad I can help. If you have any other questions let me know. I also use the big JR switch with charge jack on all my stuff, and I fly Futaba. On the ignition battery make sure the voltage is correct I have seen guys fry modules putting 6v to a 4.8v system. I will post some pics of my plane when I get them on my computer.
Old 02-20-2007, 08:50 PM
  #610  
Senior Member
 
Join Date: Jan 2004
Location: Cypress, TX
Posts: 172
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Tesla 1856,
I run two receiver batteries and two switches purely for my peace of mind. I suspect one 2000 mah battery may suit your needs just fine. I would monitor voltage before each flight and cycle the battery at the end of the day to see how much capacity you used. After a few days of testing like this, you will know if you need more capacity. I can't make a recommendation for the radio remote cutoff as I have not used one yet. I agree that the opto-isolated design is the way to go.
Old 02-21-2007, 10:02 AM
  #611  
My Feedback: (2)
 
fingers73's Avatar
 
Join Date: Mar 2005
Location: Kent City, MI
Posts: 69
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

For my radio operated kill on all my planes, I use the engine kill function on my radio. It simply closes the throttle butterfly and the engine quits.
Old 02-21-2007, 01:57 PM
  #612  
Senior Member
 
Tesla1856's Avatar
 
Join Date: Jul 2004
Location: San Antonio, TX
Posts: 257
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

I was wondering about that ... Of course, that's how I kill my glow engines. I figured it didn't work for gas since I've been reading about all these other ways people have to use to kill a gas engine.

So do you also put the choke on a servo? If not, and you operate it manually (only when starting) are they good about staying in position and not drifting closed while trying to fly (with all the vibrations and all).

ORIGINAL: fingers73

For my radio operated kill on all my planes, I use the engine kill function on my radio. It simply closes the throttle butterfly and the engine quits.
Old 02-21-2007, 03:20 PM
  #613  
Senior Member
 
Join Date: Nov 2003
Location: Tempe, AZ
Posts: 475
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine


ORIGINAL: Tesla1856

I was wondering about that ... Of course, that's how I kill my glow engines. I figured it didn't work for gas since I've been reading about all these other ways people have to use to kill a gas engine.

So do you also put the choke on a servo? If not, and you operate it manually (only when starting) are they good about staying in position and not drifting closed while trying to fly (with all the vibrations and all).

ORIGINAL: fingers73

For my radio operated kill on all my planes, I use the engine kill function on my radio. It simply closes the throttle butterfly and the engine quits.
A reason for having something other than throttle trim for killing a gas engine is that the throttle servo or linkage can malfunction. If the servo decides to die and it's at a low throttle setting, you may have to attempt to fly around for quite a while before using up your fuel (since gas engines burn it off much slower than glow). Your RX battery could run out of juice before you run out of fuel. The same situation can occur if the throttle linkage comes off. A guy at the field has his throttle servo die. It was running too fast to land but was difficult to keep it in the air. He had to baby it around for close to an hour before it finally ran out of fuel. When he checked his RX battery after landing, it was about at the critical point.

If running a choke servo and the situation above happens, you can kill the motor and land. With that said, there have been cases where the engine works loose, flexes forward, and throws-off the travel for the choke and throttle servos; meaning you can't kill the motor with the servo that's still working.

There are RCU postings on both sides of the argument regarding whether or not a TX-activated kill switch is really necessary whether running a choke servo or not. It comes down to what you feel provides acceptable safety, or what you are required to have if you are flying in competition.

Dan
Old 02-21-2007, 05:53 PM
  #614  
Senior Member
My Feedback: (3)
 
Join Date: Dec 2001
Location: Eldon, MO,
Posts: 757
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

OK Guys, I am close to having mine done. I hope to fly it Sunday. I have been reading the post but were is the perfect CG? I am running it with the OS 160.

Thanks
Crash99
Old 02-23-2007, 03:20 PM
  #615  
Member
 
Join Date: Nov 2004
Location: Meadville, PA
Posts: 65
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

I'm getting closer to completion....I pre-checked the CG by placing everything in the fuse and found that the CG is 1 1/4 inches toward the tail than the factory recomendation. The factory setting of 5 1/8 inch from the leading edge at the fuse places the CG at about the front of the wing tube. My present balance is at the rearmost section of tube. I can move my Rx 6Vt pack towards the front but after that I'll have to add weight if I want to achieve the factory CG. I have rudder servos in the tail and prefer not to move them midship unless necessary. Has anyone flown the plane with the CG I have? What extremes has the plane been flown at without problems?
Old 02-25-2007, 09:48 PM
  #616  
My Feedback: (2)
 
fingers73's Avatar
 
Join Date: Mar 2005
Location: Kent City, MI
Posts: 69
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

flyman1948

I am not sure of the exact numbers but I flew mine with a very tail heavy setup and it flew very well. Rather than add wieght, you can move your engine ahead a little and gain a lot. The motor is the heaviest ballast the plane has, making it very effective for balnce with little movement.
Old 02-25-2007, 09:56 PM
  #617  
My Feedback: (84)
 
Join Date: Dec 2001
Location: Ida Grove, IA
Posts: 681
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

I am close to finishing mine but the weather will hold me up for a long time yet. Doing the throttle linkage tonight.
Old 02-25-2007, 10:53 PM
  #618  
Senior Member
 
Tesla1856's Avatar
 
Join Date: Jul 2004
Location: San Antonio, TX
Posts: 257
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

I think I'm going to try the dual 6v battery, dual switch setup (with both connected directly to receiver).

I read here somewhere that when you do this, both switches must switch off the red AND black wires (so you can safely charge them separately without unplugging anything inside the plane)

I have been using these up till this point, but they don't switch off the black (negative) wire. It's DPDT but the red wires are bridged across both poles, and the black wire goes straight though.
[link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXH462&P=ML]http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXH462&P=ML[/link]

I really like these (since it comes with the external charge jack integrated and positioned to the ouside), but it doesn't say if both wires are switched or not.
[link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXPNU2&P=7]http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXPNU2&P=7[/link]

I would have gotten one to test with my order the other day, but they are currently out-of-stock.

ORIGINAL: Flylow

Tesla 1856,
I run two receiver batteries and two switches purely for my peace of mind. I suspect one 2000 mah battery may suit your needs just fine. I would monitor voltage before each flight and cycle the battery at the end of the day to see how much capacity you used. After a few days of testing like this, you will know if you need more capacity. I can't make a recommendation for the radio remote cutoff as I have not used one yet. I agree that the opto-isolated design is the way to go.
Old 02-26-2007, 12:13 AM
  #619  
My Feedback: (2)
 
fingers73's Avatar
 
Join Date: Mar 2005
Location: Kent City, MI
Posts: 69
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

This is the switch I use for that same purpose, I have had no problems with it. I'm not sure of the ones you have selected but I would imagine it is the same?



http://www.horizonhobby.com/Products...ProdID=JRPA004
Old 02-26-2007, 08:55 PM
  #620  
Member
 
Join Date: Nov 2004
Location: Meadville, PA
Posts: 65
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

I picked up my servos tonight and will start installing them tomorrow. Due to space, or lack of it I'm using one 166 Oz servo for the rudder at midship and using the other bay for the standard throttle servo. Ignition battery will go in engine mount box, Rx battery mounted to wing tube, This should get me close to the recommended CG.
The EMS Tower switch seems to be built by one source and repackaged by various vendors. It is the only type of switch I use on my glow and larger electric stuff anymore......
Old 02-26-2007, 10:39 PM
  #621  
Senior Member
 
Join Date: Jan 2004
Location: Cypress, TX
Posts: 172
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

I used the Hobbico HD switches on my Yak and the Ernst receptacle for charging. http://www2.towerhobbies.com/cgi-bin...&I=LXE963&P=ML . I usually charge one receiver battery at a time through the receptacle/switch harness. To charge both at the same time, I take the canopy off, unplug one battery from the switch and plug directly into the battery plug. Unplugging one battery takes it off the common connection inside the receiver.
Old 02-28-2007, 12:00 AM
  #622  
Member
 
Join Date: Nov 2004
Location: Meadville, PA
Posts: 65
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Has anyone had any problems with control surface flutter? I'm not expecting any but I'd like to know in advance. The control horns are sheetmetal screwed in an have no backing plates...is this going to be a weak spot....? Just thinking ahead...like to avoid any potential problems if possible.! Thanks ...............
Old 02-28-2007, 08:16 PM
  #623  
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

I initially had problems with the rudder because I did not have the pull - pull cables tight enough. Problem went away after I tightened them.
Old 02-28-2007, 08:57 PM
  #624  
Member
 
Join Date: Nov 2004
Location: Meadville, PA
Posts: 65
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Uncas.....

How tight do the pull-pull cables have to be....like a guitar string or a bit less....? Thanks.....
Old 03-03-2007, 07:40 PM
  #625  
Senior Member
My Feedback: (20)
 
Sewerdude's Avatar
 
Join Date: Jun 2002
Location: LaPorte, IN
Posts: 774
Likes: 0
Received 1 Like on 1 Post
Default RE: Great Planes 25% Yak 81" 12-lb, seen on Fly3D Magazine

Thinking about this Yak. From what I gather on here. The DA 50 seems too heavy? I've read that the stock landing gear spreads out because of the weight? What about the Fuji 43, I see Tower has a combo deal with this package. How does the 43 perform in this Yak? or is it not enough power. Was wondering about the all up weight with the 43 also. Thanks

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.