View Full Version : AEG GIV twin engined bomber

11-09-2008, 10:27 AM

Thought I would show an AEG GIV that I have been building lately. The build is depron, aluminium tube and some CF rod.

Power is two GWS brushed g/box 400's with a 3s 2250mah and Kontronik Sun ESC.


11-09-2008, 11:11 AM

11-09-2008, 11:20 AM
Hi Steve :ws: and Welcome to Wattflyers, Your plane is Beautiful, Very Very Nice, I am So Jelious, I cant build like that :p> Take care, Chellie

Don Sims
11-09-2008, 12:37 PM
Welcome to WF Steve! Very nice build!

11-09-2008, 01:15 PM
Love it.

11-09-2008, 06:55 PM
Thanks guys

Did a bit more work over the weekend, finished the sprung landing gear and fitted the props (9x5) for a trial. Wingspan will be approx 60 inches.

This is my first twin after building a Fokker EIII, Hannover CLII, a Fokker DVIII and an Albatros DIII.


11-09-2008, 07:48 PM
Quality work there, floss; looking great!

11-09-2008, 11:43 PM
Really nice work. Now you got the wheels turning.:rolleyes: If you dont mind, how do you shape your panels, and are you going just by "eye" or do you use a modified set of plans?

11-10-2008, 12:28 AM
K Close

I use 3-views and reference them with original dimensions to get it all correct.

Here are the 3-views that I am using for this build and a few of the other planes built using the same method.


11-10-2008, 06:41 PM
Nice to see you here Steve, I've enjoyed the Albatros build, and this one will be no exception. It's looking GREAT.

Question - did the original have counter rotating blades? I suppose you could eventually go brushless and do that, but wasn't sure what the real ones had.

Looks like it'll be a floater with those long wings.

11-12-2008, 06:13 PM
Thanks 7C7

The originals had both, some came out with C/R props and some didn't. I was originally going to do them but the guy at the local E-flight store recommended these props and there isn't a reverse or pusher prop available. I have made the ability to reverse one motor very easy if I want to use APC C/R props at a later date.

Sure hope you are right about the floater bit, I was wondering if I could fly it indoors at a reasonable sized venue.


11-15-2008, 06:30 AM
W O W !

What a plane !

Which GWS motor/gearbox do you use for the 9x5 props?

The idea with aluminum and/or carbon rods is nice.
I have to look for that, the next time I am in the hobby shop.


11-15-2008, 08:36 PM

Thanks, the motor/gbox is the GWS-EPS-400C(DX)-A which has a 2.14:1 ratio.

Some hobby shops over here carry 12 inch lengths of ali tubing but I buy the 1 metre lengths, way more value for your money. You will find the carbon rod will fit perfectly into some of the tubing to make axles and bearings etc.

You should have no trouble finding the stuff, all ours comes from the good ole U.S.A:D.


11-22-2008, 09:24 AM
Fitted the wings permanently and also made rollers for the aileron cables to go through the wing. The wingspan of the lower wing is approx 56 inches.

The original aircraft had a long-WS version that saw it increased from 60ft to 78 feet, imagine this fuselage with another 14 inches! Due to the planes heavy welded steel tube frame the extra WS was deemed necessary in the GIVb.


11-23-2008, 08:52 AM
Very nice work, floss, on those pullies; an excellent way to make them.

Its all coming together very nicely.

11-23-2008, 09:14 AM
great work!

11-23-2008, 06:56 PM
Fantastic work Steve! Subscribed! Martin

11-23-2008, 09:05 PM
Floss you must share with us/me how you built the Albatross and the DVIII (my favorites along with the DRI)! :) Are plans available from you? Building advice? :ws: I have MANY sets of plans for WWI planes (mostly fighters). Perhaps you would like to trade. :D If you need a list I can post. Let me Know. Martin

11-24-2008, 04:42 AM
HERR FLOSS, very nice build! As mentioned above...more details PLease...For me I'd like to know how you joined the wings, and a bit more on how the aileon set-up works....keep it up!!!

11-24-2008, 10:15 AM
Thanks guys, glad to share any advice if it can help.

I don't work off plans as such, just 3-views. The shortcut to the DVIII below best shows how. The Albatros DIII was differant because I wanted to do the skin with balsa to replicate the ply fuselage. I still have not maidened it, summers just arriving here now after a nasty wet winter.

Martin, glad to help in any way. Building this way is far simpler then it looks.

Rhino, the pulleys are four small pieces of aluminium tube with two washers epoxied onto each. The shaft that the pulley sits on is a piece of CF rod simply epoxied into the depron.

Barmonkey, the outer section of the wing is a straight epoxied butt up to the inner section. I glued four evenly spaced small segments of toothpick sharpened at each end into the inner wings edge and guided the outer wing onto them to help me keep it aligned while the 5-minute epoxy cured. Any two depron edges epoxied in a simple butt joint such as this will be stronger then the actual depron itself. Simple is best.

The ailerons system is a loop just like the real thing. The central servo in the fuselage activates pulling down the leading edge of either aileron, each aileron trailing edge is linked by cable to the opposite aileron on the trailing edge so if one raises it pulls the other down and vice versa.




12-01-2008, 08:35 AM
I did the fun part on Saturday morning, hooked up the ESC, RX and motors and had a test run. One of the fun parts of this hobby is that there is always a surprise of some sort in the offering and the surprise with the test run was the amount of thrust on hand with the twin motors and props. Three clicks of the throttle was all that was possible, just two clicks had it wanting to taxi fast. I will either have to dull down the throttle response or fly under half throttle, still better then being underpowered though.


12-02-2008, 01:06 AM
Agreed! More power good! Not enough bad! Martin

12-20-2008, 01:10 AM
With lower wings painted.

12-20-2008, 09:23 PM
Floss, that is sweet!

12-23-2008, 07:01 PM
Looks amazing! really impressive painting, and of course modeling.

12-28-2008, 02:02 AM
Top wing (6mm depron) getting fitted after rolling to give it camber and then gluing the two halves together.

It will be removable (without rigging) with 2mm screws and nuts as fasteners.


10-27-2009, 09:15 AM
Carrying on today I fitted the four outer struts and then rigged her all up. I fitted 5 dacron hinges to each aileron and then epoxied them into the wing

Only thing left besides painting is to fit aileron horns and then connect the servo up to them both with some nylon.


Don Sims
10-27-2009, 10:58 AM
It's looking great floss!

10-27-2009, 03:32 PM
Wow, it's been a while! NIce to see you at it again.

10-31-2009, 10:14 PM
Cheers guys.
Finished the aileron set up yesterday so thought that basically it was ready to test fly. Later I got out the TX to set the throws and noticed that the aileron servo (1 x Hitec HS55) was not moving one way after a few test movements. Swapped it out for another and watched that one deteriorate before my eyes as well. Basically I think now that the loop aileron set-up on that big wing is too much for one HS55 and I think I managed to kill two of them just playing:(. An expensive experiment but I learnt a lot.

Moral of the story here: If you try for bigger things the same old servo's that always did the trick may not do it anymore:rolleyes:.

Will get a bigger high torque servo today, meanwhile here are a few pics.


11-01-2009, 04:40 AM

I hope I'm seeing this right, maybe you should change the angle that the aileron cable goes up to the top aileron. Either the aileron control horns need to be twisted to be at more of a right angle to the cables or the aileron cables need to be routed up closer to the leading edge of the wing, and then to the control horn.

Otherwise the cables have to pull much, much harder on the control arm to get the aileron to move, thus overpowering your HS-55s!

Outstanding job on your AEG GIV!!! I have been following your build on this from the beginning and it is gorgeous and I learn something new with each post. Thanks for bringing all of us along for the build!


11-01-2009, 07:42 AM
Yeah fair comment, I wondered about that. I copied the original set-up. It doesn't seem to take too much to pull the cables and more importantly it does'nt warp the wing when activated but with a wingspan of around 58 inches the 130+ inches of tight nylon was still too much for one little HS55.


11-01-2009, 09:33 AM
i think the problem with the ailerons is not the servo and not actually the cable routing but the horn design. The real AEG had the cables routed as you have them but the horn was very different. The top horn was angled forward just above the wing and i think moved down into a slot in the wing when the aileron went up. The bottom horn was not really a horn at all the cable attached to the actual aileron half way between the hinge line and the TE.

As you have it the bottom cable is pulling directly in line with the hinge, so there is no leverage to move the aileron, it will just pull the whole wing down, or attempt to.


11-01-2009, 09:50 AM
Here's a rough sketch to show how I believe the AEG ailerons was rigged. This will work fine on your model too and I'm sure will save your servos. Note that the distance between the hinge and the cable attachment points should be equal.:

11-01-2009, 10:29 AM
Thanks and yes you are correct about the top horn being differant. The ailerons work well, nice smooth movement and equal also. The wing does not twist or pull down with the actuation. I was using a single centrally located micro servo to work cable ailerons on a wing that almost spans 60 inches. This servo is made to work the elevator in a 12oz model with a single pushrod and I had it hooked up to 130 inches of tightly drawn nylon. The ailerons action worked great 30-40 times and then would slowly decrease their movement and the servo would sound stressed, the LHS owner said the motor in an HS55 would never handle the pull required and thats what would have given out. Add to this also the HS55's reputation for not liking abuse, they are not a strong servo. I bought a servo with 2.5 times the torque of the HS55 to do the job. To change the set-up at this stage would be redesigning it simply to try and make an undersized servo do a job it never will. I do like the horn idea that you have drawn though.

11-01-2009, 11:16 AM
I wont labour the point any further but the arrangement you have will never work properly regardless of how strong the servo is because the mechanics are wrong, .. If the servo was powefull enough it would just pull the wing down or pull the hown away from the aileron.

Your call though...

Brilliant model by the way.


11-01-2009, 10:01 PM
Ok on a day off I made some changes to the horns along with fitting the new servo. I trimmed the lower horn right back until it is basically just an attachment point on the aileron surface. Also I shortened the length of the top horn so that when it comes down the cable attachment point is in line with the cable path through the top wing if that makes sense. Have got to run new nylon but I am confident the three alterations will make the system more efficient. Thanks to Steve and Dave for your input guys, great stuff.


11-01-2009, 10:14 PM
That may be some improvement but to get it right the bottom control wire attachment really needs to be set back on the aileron, like in the sketch.

A powerful servo may cover up for incorrect geometry but even if the servo is bullet proof there will be a lot of stress caused which could lead to failure of the horn, hinge, wire, wire guides etc.. So be carful and test it very thoroughly.

11-02-2009, 04:16 AM
Works fine but you are right Steve, if the lower attachment point was further back the servo would do less work. I weighed it today flight ready with battery and a small lead fishing weight up front to be safe with the CG, 36.5oz. Not too bad as the battery is a 3S 2250mah. Greased the motor pinions, set all throws etc. Greased all the cables and put some velcro in the battery compartment to hold it in. I will rout the aerial, make sure the wheels all are as free as each other and then the weather is all that will be left.

11-02-2009, 05:16 PM
I use pull-pull on most of my WW1 planes. You need the hookup equal on both the horn and the servo, if the pull side moves 1/2 inch the slack side needs to move 1/2 inch too, if not it will bind. Now moving the wire into a different hole on the sevro is ok as long as you change both sides, same at the horn. You also want the holes on the horns to line up in a straight line with the hinge. Holes at the servo need to be in a straight line with the screw that attaches the servo arm. This is the easy way to keep everything blanced. If something does not line up then you need to change something somewhere in the system to get the blance back and that takes some work.

11-02-2009, 06:25 PM
It's looking great. I also was sharing the same concerns about the geometry. Didn't see that until a couple minutes before typing this. I feel Jet has steered you straight. The illustration he provided is exactly what I was thinking before seeing it. I did this setup (pull pull with single servo) on my Albatros, and it works wonderful.

If you're still at all concerned, and you want some more leverage from the servo, extending your top horn forward (like drawing) and moving your idler string rearward will give you that.

On my SE5, (4 ailerons, with scale Pull/Pull) I used an HS65 HB with the carbon gearing. It was lighter than 2 HS55's, and is working great.

11-13-2009, 09:25 PM
Floss - Aha, so this is where you have been hiding. I was just wondering what happened to the AEG G.IV thread on R/C Groups and here you are. Looking good!

11-23-2009, 06:52 PM
Floss - Aha, so this is where you have been hiding. I was just wondering what happened to the AEG G.IV thread on R/C Groups and here you are. Looking good!

Hi Mate
Yep been undercover here for a while, the AEG is ready to fly a maiden. Been away for work the last 8 days (Germany funny enough) so just saw this a few minutes ago.

Very windy and dull November here but will definately let you know how it goes once I get the all clear from the tower :ws:


02-11-2012, 11:31 PM
Steve-- Did you ever fly the G.IV? I'm waiting for a Datafile to arrive so I can work up drawings for a 30" span indoor flyer. Really like to hear how yours did.