Carl Goldberg Electra (First real flight) - RC Groups
Thread Tools
Jan 19, 2007, 06:20 PM
Gotta make the doughnuts

Carl Goldberg Electra (First real flight)

While off the week of Christmas I built an Electra like the one I had and promptly crashed over and over when I was 13. Since it was my first plane I thought I would built it again now that I've been flowing glow planes for a while.

About a week ago I got her up long enough to know I had to reduce the downthurst and reduce my elevator and rudder travel; not enough to consider a true flight.

Today I finished up work with enough day light left to go get in a quick flight.

Wind was 17-18MPH steady. Temperature 27F / 16F Windchill.

I almost didn't fly because of the wind. Anyway, this is an entirely different animal than flying glow planes!

The plane flew on it's own but controlling it was pretty hard for me. Mostly due to the wind, but it just does not handle anything like a glow. It was just "weird" on getting it to make turns especially with the wind.

I lost my ailerons once on one of my glow planes and was able to make a controlled landing with the rudder, but this was nothing like that.

At one point I was nose up into the wind just floating in one spot. When I hit the rudder it didn't do much of anything. Thinking it would probably do a loop if I pulled back on the stick, but knowing it's the only way to make it turn I gave it a shot. Suprisingly the tail kicked right around. I practiced this a few things. I think I need to cut back on my controls some more though because the tail would just whip around.

I've already limited my movements to 75% of the specifications, so I'm assuming I should take the wind speed into consideration.

Anyway, I'll hold off on flying until this is a warmer and calm day.

Oh, the landing was amazing. I was assuming I would come in and slide. Nope. Nose to the wind she just kind of came down (Of course I'm battling the wind to keep her level) and at about 4 feet off the ground she hovered in one spot then gently set straight down while the wind kept her aloft.

Any thoughts? I could use a couple tips and tricks I might not recognize from the glow world.

Sign up now
to remove ads between posts
Jan 19, 2007, 06:35 PM
Registered User
rchawks's Avatar
Well for one thing that's quite of bit of wind to fly her in unless you're on a slope. I'd try again in calm conditions and I think you'll find it much different. It is a floater class after all and about all you can do in 15 to 20 mph winds is tack it into the wind. You could add ballast but I'd just fly it in 10 mph winds or less, it will be much more enjoyable that way. It is a kind of a light duty boxy kind of fuse, it wouldn't take very much abuse before breaking. I had one years ago and flew it for years before totaling it. I was teaching a friend to fly it and he pulled the wind off and it dropped from about a thousand feet. It was my fault, I had a weak link in the wing attachment. You're not going to get the penatration in 20 mph winds that you would with many other planes.
Jan 19, 2007, 06:54 PM
Gotta make the doughnuts
That makes sense. I'm used to flying 35-70 MPH and having razor sharp precision and control.

I'm not sure if I'll like the slow flight, but it's "easier" since it rights itself.

It make a noise a couple times, not sure what it was. But when I banked and put the wind to the tail it really cruised along and made a nice "whisp" through the air. I had to pull up and bank right to keep her from getting to far away and when I did there was a thump sound. The thump sounded like like if I flicked the monocoat between wing ribs.

I couldn't find any stress damage or problems with the monocoat. I'm wondering if the thump was the fuse pulling away from the wings and then snapping back in place?

I used 6 rubberbands. I think I'll up it to 8 or 10. I do love speed and pulling out of a fast dive, but I'm sure this plane isn't made for that.

I'm using the stock Carl Goldberg 550 motor with 3300mAh NiMH cells.

I have an ESC on it and I keep reading about a "break" on ESC but I'm not sure if that means it will stop the prop in a certain position so it doesn't catch on the ground or if it just means it stops like mine does.

I think she looks nice. I haven't applied monocoat since I was 13. All of my other planes are ARF's. But after building this I did order a Sig Somethin' Extra and a Four Star 60 kit. It's just more fun to build them on your own, especially since you're much more familiar with the plane and build.

I remember when I was 13 I forgot to do a couple things, but it didn't affect it. I'm 29 now. I was amazed I actually built this thing on my own when I was 13 and actually did a great job without any help or even knowing anybody who flew.

So I think I'll go take a couple quick pictures.
Jan 19, 2007, 07:11 PM
Registered User
rchawks's Avatar
The plane is much more "enjoyable" in it's element. It works best and you'll have the most fun with it flying very high and far away (thermaling). It's structure and airfoil isn't designed for the kind of flying you enjoy doing. Slow flying has it's own rewards too. Calm sunny days or even overcast and calm are what works best for this plane. The thump you heard could very well be the wing pulling away from the fuse in a high g turn. It could also be vibration from flying so fast. I'd check the wing carefully with your hand and lightly flex or twist (lightly) the wing to feel any softness in the wing. Short of cutting away the monokote that's about all you can do. But the wing isn't designed for high stress unless you do some modifications. Even then only so much can be done.
You mentioned 3300 cells, how many? Sounds like you have quite a bit of weight in it already. The only packs I have of the 3300 are 8 cell and they carry a bit of weight. I use them in my heli.
The break refers to stopping the prop from rotating in foward flight with the motor turned off. It's very annoying to fly with the prop freewheeling. Using the break is a good idea.
By all means post some pics!
Jan 19, 2007, 08:03 PM
Ascended Master
Sparky Paul's Avatar
It'll fly a lot easier in less wind, and at less weight.
You have a good 2 times more battery than you need.
It's a glider, not an aerobat.. the wings aren't really built to take heavy loads with that much weight.
You could easily lose a lot of weight by going to half that capacity in Nimhs, and even less with Lipos.
Jan 19, 2007, 08:19 PM
Gotta make the doughnuts
Here's some pics. The electrical tape on the wing tips is covering some wires I've routed through the wing. I'll be putting some high intensity LED's in the wings, just for kicks and have them blink every few seconds.



Jan 19, 2007, 08:20 PM
Gotta make the doughnuts


I had to adjust these all in Photoshop. The lighting was off. A couple of the nice pictures didn't turn out but there are good enough I think.

Jan 19, 2007, 08:24 PM
Gotta make the doughnuts
What's the weight difference we're talking about? These are "Venom 3300" I picked up. I was worried about not having enough power when needed. I was also figuring I could cut the power out, glide down, then power back up. I could pick up some lighter batteries and just change them out depending on my mood or what I want to do.

When I was 13 I believe I had a 1500 NiCad in it. They just happened to be batteries I had left over from a Sears Lobo RC car from when I was probably 10 or 11! (When I say in it, I mean the Electra I had when I was 13 and tried to learn to fly on my own without having any input or help. It did a giant loop, right into asphalt my dad had helped me launch it from. It didn't help he threw it at a 45 degree angle up.)
Jan 19, 2007, 09:37 PM
Ascended Master
Sparky Paul's Avatar
Looking at the Hobby Lobby catalog for batteries..
A 7-cell 2400 mah Nicad weighs 15 oz.
A 7-cell 2600 mah Nimh weighs 16 oz.
A 2-cell Lipo (equivalent to the 7-cell) at 1500 mah weighs 3 oz.
Taking almost a pound of weight out of the plane will really pep it up.
Changing to a 3:1 gearbox and 12x8 folding prop will also pep it up it more.
Jan 19, 2007, 10:11 PM
Gotta make the doughnuts
I was condering doing the gearbox and I did try a folding prop but being I'm not experience in electric flight, the folding prop didn't do anything as is. I'll have to read up on that more.

I'll see how the flying goes, if I'm pretty into it then I'll go with the lipo setup. I'm still a glow plane fan.

Anyway, I checked out your site. You have a LOT of info posted there. I have a Kadet Senior I have yet to fly, I'm shocked you have it clocked at 70MPH.

I have one plane I like to put into a steep dive and then pull out of once I have some good speed built up and just buzz right by overhead.

Well I know I figured I'd set the plane aside, but now I'm thinking if tomorrow is calm maybe I'll take her up again and see how she handles. [EDIT: Helps to check the weather. Being it will be in the 20's tomorrow with 15mph winds that's a negative]
Last edited by Rhathid; Jan 19, 2007 at 10:19 PM.
Jan 19, 2007, 11:20 PM
Registered User
rchawks's Avatar
I used a 1200 nicad (6cell) in mine at the time, then up it to a 1700 nicad (cell) later on and it worked very well.
Be forewarned the lypo setup does take much more responsibility. The power to weight ratio is amazing though.
Since you love flying the fast glow stuff it sounds like the diamond dust (look at my avatar) may be up your alley. A very good friend of mine designed it and he has flown his at over 250 mph. This plane can be put into a full pwr dive with a snap at the bottom, incredible!
Jan 20, 2007, 11:41 AM
Gotta make the doughnuts
I've read up a bit on the lypo's. I've always been into eletronics (My dad worked for Edison, had me wiring up stuff started when I was 6).

Thinking about shedding a whole pound off the plane is a catching idea. I've never been to concerned about some extra weight, mostly because of flying the glow there was always more than enough power.

The ESC can power the receiver off the motor battery, so you guys have me thinking about getting a lighter motor, gearbox, 12x8 folding prop and going to lipo in which case I can yank the receiver battery because of the supply it creates. That would be a lot of weight!

That's basically all new guts, so I might as well see if I like flying the sailplane and if I really want to get into this area as well, just buy another kit to build up. I'd have to read up on the various and best sailplanes out there though.

When I took my first glow plane to a field for my 2nd attempt to fly it a guy showed up with a sailplane and a small OS motor on it. By the time I noticed him he already had it up. He was thermally with some seagulls pretty far away. He was up there at least an hour. I didn't know where the plane was until I walked over and asked him. It was pretty far away, as well as high!

Anyway, where can I get more info on that diamond dust?
Jan 20, 2007, 11:52 AM
Electric Airplane Junkie
bhchan's Avatar
Originally Posted by Rhathid
When I took my first glow plane to a field for my 2nd attempt to fly it a guy showed up with a sailplane and a small OS motor on it. By the time I noticed him he already had it up. He was thermally with some seagulls pretty far away. He was up there at least an hour. I didn't know where the plane was until I walked over and asked him. It was pretty far away, as well as high!
The thing about using a glow engine is it had enough compression to stop the prop from spinning after the engine die. With an electric motor, a fixed(non-folding) prop will spin and create drag. With the condition you stated(20mph + wind) , all the drag created by the spinning prop will stop the plane froom going anywhere.

Brian, an EAJ
Jan 20, 2007, 12:00 PM
Gotta make the doughnuts
That's interesting, that seemed to happen. The only way I was able to get the plane bac to me was by climbing higher and higher and then putting it nose down in my direction. At that, it enough took a couple passes before I was able to land.

Any idea on what size folding prop I should get? I mean, I already tried one that was slightly bigger than the stock Electra prop and when I launched it, it just glided to the ground. I tried it a few times thinking I needed a harder launch and on the last attempt I shattered the blades off because I was focusing on keep the plane level and didn't cut the throttle in time.

FYI - RCHAWK - I checked out the DD and a few other planes like it. Very cool! Although it looks like a flying baseball home plate. I like the scale look, but if I can zip by at 250 MPH and the kit is only $65, I think I'll build it after I finish my Somethin' Extra and 4*60.
Jan 20, 2007, 12:22 PM
Panda Panda Panda Panda Panda
rdwoebke's Avatar
I think there is a glider group in Toledo. You should try to hook up with them. Seeing pilots thermal or getting tips on thermals will incrase the fun factor. It is neat to have a plane climb from 300 feet to 1500 feet in a few minutes without using any motor.

I'd concur that 18 mph steady is a bit too windy for the electra if it is your first time working with it. I used to have a Gentle Lady, and did fly and thermal it in 18 mph winds, but at that speed you are kind of flying a kite, aka you point it into the wind and sort of park it there. You are not going to be doing laps or what not in those winds with the Electra.

Oh, and nice job on the build.


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Carl Goldberg Electra launchquestion Mr Abe Electric Sailplanes 11 Jun 24, 2004 06:51 PM
Finally.......her first REAL flight! thazy2 Electric Heli Talk 5 Apr 17, 2004 12:01 AM
carl goldberg electra with motor chris-miranda Aircraft - Electric - Airplanes (FS/W) 9 Apr 12, 2004 06:18 PM
First real flight of the Mirage 15/2 kushal_22 Foamies (Kits) 4 Jan 19, 2003 03:09 PM
First real flight of repaired zero today! bztguy Parkflyers 3 Apr 27, 2002 12:32 PM