New Products Flash Sale
Thread Tools
Old Jun 11, 2010, 02:54 PM
Pilot28 is offline
Find More Posts by Pilot28
Registered User
Pilot28's Avatar
Joined Apr 2010
178 Posts
Cool
Apprentice 15e as a Towplane?

I have an Apprentice, and I was wondering if I could make it a towplane.
Pilot28 is offline Find More Posts by Pilot28
Reply With Quote
Sign up now
to remove ads between posts
Old Jun 11, 2010, 03:47 PM
freechip is offline
Find More Posts by freechip
Air, Ground & Water
freechip's Avatar
Canada, ON, Rockland
Joined Aug 2008
26,767 Posts
How much trust do you have and are you still using the stock power setup?

Not 100% sure but I think you may need a plane with tons of power to pull another. Not sure the Apprentice falls in that category.
freechip is offline Find More Posts by freechip
Reply With Quote
Old Jun 11, 2010, 07:00 PM
fmw is offline
fmw
Find More Posts by fmw
fmw
Registered User
fmw's Avatar
Joined Jul 2009
1,955 Posts
The apprentice has enough power to pull a couple of pounds of glider. It is significantly more powerful than most trainers.
fmw is offline Find More Posts by fmw
Reply With Quote
Old Jun 11, 2010, 07:17 PM
Xpress.. is offline
Find More Posts by Xpress..
Hitec RCD CSR
Xpress..'s Avatar
United States, CA, Alpine
Joined Oct 2007
22,020 Posts
Yes it'll do fine pulling a glider like the Easy Gliders and such
Xpress.. is offline Find More Posts by Xpress..
Reply With Quote
Old Jun 12, 2010, 05:12 AM
verticalspark is offline
Find More Posts by verticalspark
Aut Viam Inveniam Aut Faciam
verticalspark's Avatar
United States, CO, Colorado Springs
Joined Oct 2008
4,154 Posts
yup, you should be good up to about a 2m glider. After that you may be pushing the limits of the stock setup of the apprentice
verticalspark is offline Find More Posts by verticalspark
Reply With Quote
Old Jun 12, 2010, 04:58 PM
Thomas B is offline
Find More Posts by Thomas B
Electric Coolhunter
Thomas B's Avatar
United States, TX, Fort Worth
Joined Jun 2000
14,887 Posts
Funny you should post about this idea....

Been doing just that, just last week...here are some pics of Richard Ng's stock power system Apprentice aerotowing his vintage Raven flying wing sailplane just last week in Little Rock at the SMALL Steps 2010 event. (GREAT event!) I am the big guy at the far right in the first pic, flying his Apprentice for the tow.

I also dug out a very old piggyback rack for launching small gliders from the back of a glow R/C model, rebuilt it and did some piggybacking as well. Piggybacking is much easier than aerotowing, with small models. A servo in the rack releases rubber bands that hold the glider to the top of the rack. As Richard had the stock AR500 RX and has already added flaps to the Apprentice, we used a y harness to hook in the piggyback release servo and simply activated the flaps to release the payload. Note the deployed flaps in the pictures of the piggyback gliders being released.

For towing, we opted for no release on the towplane. However, if you do not have a towplane release, you really ought to use a weak link of 4-6lb monofilament for the towline, which is what we did. That way, if the glider release fails, you can do a break-away and still escape the towplane. Our towline was made from some 12lb test Spiderwire, with a metalized mylar streamer on the glider end, for visual confirmation of glider release.

We left the piggyback rack on top during the tow...pics also included of the Apprentice piggybacking my Alula and a old Klingberg Rocket Wing, with an Estes D12P motor that ignites in mid air, using a brushed ESC as the ignition source.

The stock power system is only good for a couple of pounds of glider on tow. Weight and drag on tow it more of an issue than size actually is.....but it is not only that. No matter the power, when the weight of the glider gets to be a good portion of the mass of the towplane, the glider starts steering the towplane a little too much.

It hardly knows the Alula and rack are on top, with the stock power system. The stock landing gear was not quite up to the heavier Rocket wing, and it needed a hand launch for that one...

We are going to pump up the Apprentice with a better motor and a 4S pack here soon making at least 50-75% more watts, for somewhat heavier gliders and a quicker tow or piggyback to altitude...

Richard also flies this Apprentice as a float plane...it is one awesome multi purpose model!
We worked it pretty hard for three days at SMALL....
Thomas B is offline Find More Posts by Thomas B
RCG Plus Member
Last edited by Thomas B; Jun 12, 2010 at 06:05 PM.
Reply With Quote
Old Jun 12, 2010, 09:23 PM
laryctdummy is offline
Find More Posts by laryctdummy
Registered User
laryctdummy's Avatar
colorado
Joined Apr 2009
97 Posts
I used one to pull a MP Easy Glider worked GREAT!!! PM me if you want good photos for an easy build tow release. I used a HS-55 and a home built hook that added next to no weight. -Joe-
laryctdummy is offline Find More Posts by laryctdummy
Reply With Quote
Old Jul 29, 2010, 06:26 PM
Pilot28 is offline
Find More Posts by Pilot28
Registered User
Pilot28's Avatar
Joined Apr 2010
178 Posts
Yeah, I use mine as a towplane too.
Pilot28 is offline Find More Posts by Pilot28
Reply With Quote
Old Jul 15, 2015, 11:23 AM
Younggun84 is online now
Find More Posts by Younggun84
Registered User
United States, TX
Joined Jun 2014
44 Posts
Bumping this thread instead of making a new one.

I'm trying to piggyback a free flight glider on my apprentice. It's all stock except it no longer has the SAFE receiver as I wanted a couple of extra channels.

The glider is really just a $3 foam plane from Family Dollar. Almost no weight, I added a bit to the nose just to get it to fly right at high speeds when hand launching.

I built an incredibly cheap and unsophisticated test release that mounts on top of the wing at about CG. It's nothing more than a piece of exercise mat with a wire on one side and servo on the other to release a rubber band. It is held down by the rubber bands that hold the wings in place.

Here's the issue I'm having and have had with other things mounted on top of the wings. THe plane won't come off the ground. I had a small box there at one point that made the plane want to dive, I thought this might not be as bad since the glider will generate some lift on it's own but it's like the Apprentice is glued to the runway.

How do you get your piggy back planes to come off the ground and why is mounting something in an area that really doesn't generate any lift causing so many issues?

Thanks for any tips.
Younggun84 is online now Find More Posts by Younggun84
Reply With Quote
Old Jul 15, 2015, 11:27 AM
Younggun84 is online now
Find More Posts by Younggun84
Registered User
United States, TX
Joined Jun 2014
44 Posts
Here is a picture I took of the test platform
Younggun84 is online now Find More Posts by Younggun84
Reply With Quote
Old Jul 15, 2015, 04:59 PM
3rd Try is offline
Find More Posts by 3rd Try
Registered User
United States, NY, Champlain
Joined Jul 2012
381 Posts
Raise the nose of the glider so "it" has a positive angle of attack.

Regards

Dennis
3rd Try is offline Find More Posts by 3rd Try
Reply With Quote
Old Jul 15, 2015, 10:33 PM
Younggun84 is online now
Find More Posts by Younggun84
Registered User
United States, TX
Joined Jun 2014
44 Posts
Thanks.

I found another issue that's not helping. It seems the last crash I had caused some damage to the motor. Guess I'll have to get that fixed before I continue this project.

I'm the mean time, I will work on a new mount that holds the nose up a bit.
Younggun84 is online now Find More Posts by Younggun84
Reply With Quote
Old Jul 16, 2015, 07:30 AM
Thomas B is offline
Find More Posts by Thomas B
Electric Coolhunter
Thomas B's Avatar
United States, TX, Fort Worth
Joined Jun 2000
14,887 Posts
When attaching a model piggyback, you need to avoid too much disturbance of the air over the center section of the wing. With the little glider so close to the wing surface and with that exercise mat, you are likely tripping a lot of air that is turbulating over the horizontal stab and making your elevator ineffective.

With our setup pictured above, there is some loss of elevator effectiveness just from the piggyback structure.

With a glider that small, you would be better off attaching it to the bottom of the fuse, inverted, as long as the vertical tail has some clearance to the ground. When you release it inverted, it will simply loop around and settle into a normal glide.
Thomas B is offline Find More Posts by Thomas B
RCG Plus Member
Latest blog entry: 2014 events and travel
Reply With Quote
Old Jul 16, 2015, 09:42 AM
Mattfly is offline
Find More Posts by Mattfly
Mattfly's Avatar
Champaign. Illinois
Joined Jun 2003
822 Posts
The Apprentice was our go to tow plane when I did the Parkzone KA-8.

Parkzone Ka-8 Segelflugmodell von Horizon Hobby (2 min 3 sec)


Matt Andren
Horizon Hobby
Mattfly is offline Find More Posts by Mattfly
Site Sponsor
Reply With Quote
Old Jul 16, 2015, 11:13 PM
Younggun84 is online now
Find More Posts by Younggun84
Registered User
United States, TX
Joined Jun 2014
44 Posts
Quote:
Originally Posted by Thomas B View Post
When attaching a model piggyback, you need to avoid too much disturbance of the air over the center section of the wing. With the little glider so close to the wing surface and with that exercise mat, you are likely tripping a lot of air that is turbulating over the horizontal stab and making your elevator ineffective.

With our setup pictured above, there is some loss of elevator effectiveness just from the piggyback structure.

With a glider that small, you would be better off attaching it to the bottom of the fuse, inverted, as long as the vertical tail has some clearance to the ground. When you release it inverted, it will simply loop around and settle into a normal glide.

I'd considered this but wasn't sure about clearance issues.


Still working through the power issue right now. Seems most advice was pointing towards the motor being the probably cause. Replaced today's and was able to get off the ground but couldn't climb. Plane was in a mesquite tree before I could get it to a safe landing area. Guess I'll be replacing the ESC.

In the mean time, I'll scratch the piggyback method and work on an underbody mounting system.
Younggun84 is online now Find More Posts by Younggun84
Reply With Quote


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion E-Flite Apprentice 15e replacement aileron servo arm, pushrod and clevis jono80 Beginner Training Area (Aircraft-Electric) 14 Feb 25, 2012 07:15 PM
Discussion Apprentice 15e crobar Foamies (Kits) 8 Apr 23, 2010 03:16 AM
Found WTB: E Flite Apprentice 15e RTF no radio sarasota_krash Aircraft - Electric - Airplanes (FS/W) 0 Apr 01, 2010 11:25 AM
Discussion e flite apprentice 15e as a first plane Xombie2000 Beginner Training Area (Aircraft-Electric) 15 Mar 23, 2010 02:54 PM
Discussion SuperCub LP BNF vs. Apprentice 15e RTF...opinions wanted mdwood Beginner Training Area (Aircraft-Electric) 33 Mar 15, 2010 02:36 PM