KMP "Challenger II 80" [Archive]

donjiskra

Mar 26, 2007, 04:20 PM

Anyone familiar with this beautiful model?

http://www.kmp.ca/product_info.php?cPath=36&products_id=145&osCsid=e825935dac87b753af89820c6bad1796

They say it can be E-powered:
"Designed for gas, (40-52 two cycle), This model makes it an excellent candidate for electric power.The reason for this is it's very light airframe weight (7 to 8.5 lbs), and the need to put 'pilot weight' (lead or batteries) forward to simulate the real weight and balance."

Perhaps someone has done it???

Thanks for your reply,
Don

Michael in Toronto

Mar 26, 2007, 08:10 PM

There is an owner of a local hobby shop (Ron) who is building one with an E-Flite 46 brushless motor. He says it will balance well with batteries in the nose, but he has to drill out the lead weight that comes in the nose.

He doesn't use this website, so I guess you can call him, if you want.

Pinnacle Hobby
5970 16th Avenue
Markham, Ontario, Canada L3P 7R1
(905) 471-9634

Hiflyer

Mar 27, 2007, 06:07 PM

donjiskra

Mar 28, 2007, 08:18 AM

Hey Mike, that's good news!
Appreciate your very helpful informative reply.
Look forward to the video and availability to your product line.
Don

Hiflyer

Mar 28, 2007, 06:51 PM

I just posted a video of the Challenger II

http://www.rcgroups.com/forums/showthread.php?t=663714#post7175826

check it out.

Mike Hines

Vagabond324

Apr 03, 2007, 10:56 PM

I just posted a video of the Challenger II

http://www.rcgroups.com/forums/showthread.php?t=663714#post7175826

check it out.

Mike Hines
Hi Mike, that's one sweet flyer. Do you think it needs 2 2s1p 5000 Lipo's? I have a 4s1p 4000 mah Lipo that I was thinking of using for this setup. Thanks, The Vagabond ;) , Jon

Hiflyer

Apr 04, 2007, 10:47 AM

Vagabond324

You could easily use the pack that you have. We balanced the plane with the packs back in the fuselage quite a bit, so balance should not be a problem. Flight times should also be acceptably long with your packs.

Good luck

Mike Hines

patrickegan

Jul 20, 2007, 01:54 PM

Mike,

I have few questions if that’s okay? (Electric version) What the AUW and normal flying duration(s)?

Thanks, Patrick

Hiflyer

Jul 22, 2007, 12:19 PM

Patrick

The ready to fly weigh of ours came out at 8-1/4 pounds. At that weight the model is a joy to fly and performs very well. One of the keys to the good performance with this electric setup is the Aero-Naut three bladed folding prop. We screwed the blades tight so they do not fold. The Aero-Naut blades are very efficient and the 3 blades are necessary to absorb the power and turn it into thrust. Since you do not have the option of going to a larger diameter, due to interference with the tail boom, more blades at the largest diameter that you can use is the option of choice.

While there are fixed 3-bladed props available, most are designed for glow power and are not all that efficient in electric motor use, the Aero-Naut works very well.

Hope this helps,

Mike Hines

patrickegan

Jul 22, 2007, 12:29 PM

Thanks Mike, but was 10 min all you got out of the 2 batteries (Normal flying)?

pdemon

Jul 30, 2007, 07:25 AM

Hi
I've just bought this model and I'm starting to built it. A disappointig thing (thinking about an electric conversion) is all that lead, almost 20 ounces, that has been glued in the nose with epoxy and microballoons. It's nightmare to remove it. I ended cutting the nose just half an inch from the front gear former. I'll remove the lead and then reinstall the nose, using it as an access hatch for lipos or telemetry equipment.
Another upgrade is changing the tiny wheels with some "tundra" ones: I already have installed main gear 3 3/16" balloon air type wheels. For an aerial photography workhorse, I think this plane is a good starting point.
Pierluigi

patrickegan

Jul 30, 2007, 10:11 AM

We're on the same page. Did you order the one from Hobby-lobby or KMP?

pdemon

Jul 30, 2007, 02:58 PM

I ordered it in Europe from Lindinger.at.
Buying it from the States was too expensive.
Here are a couple of pics of the first mods
Pierluigi

patrickegan

Jul 30, 2007, 08:13 PM

nice

diver don

Jul 30, 2007, 09:39 PM

Good looking bird.

Does the one from HL have the lead in the nose?

Thanks,

DD

bhchan

Jul 31, 2007, 01:25 AM

I got one from Hobby Lobby, BUT the one I have is all white, no other color on it. I also received an instruction that is NOT for the same version of the plane that is in the box. The instruction on KMP.ca web site has the instruction for the latest version.

I have stretched the tail boom out 2 more inches, it just look too short. I have a Hangar 9 Cub sat next to the Challenger II, the Cub is about 4 inches longer.

I also have drill out the lead (Yes, the one from HL had the lead in it).I rather carry live weight(battery) and dead weight(lead)! I also reinforced the front cabin support, I glued two 6mm carbon tubes( one on each side) behind the front cabin struts. from the front bulkhead to the root rib. I think I will feel more comfortable when I pull up.

The plane is designed for glow power, I needed about 1 inch stand off to get the prop far back enough to clear the fuselage. The biggest prop I can fit on it is 11 inch. I will put an Aveox 1010/2Y , 4.4:1 Gearbox on 4S pack on the C-II.

I am not too crazy about the wing strut arrangment, the set screws can come loose if there is any vibration; if that happens, I don't think the wing joinner is going to hold the wing for long. I like a more positive lock system, like a clevis. Also the fuselage attachment point seem to be weak. It is attached to the fuselage side with a 1/2" round plywood washer inside to spread the load to the fiberglass fuselage. I plan to put a cross brace to tie the two attachment points together.

If you are going to power it with e-power, you might want to find a better way to install the windshield. The canopy is attached via 8 small sheet metal screws, multiple remove/install of the windshield to change battery might resulted in breaking the windshield. Also there is no air exchange from the cabin, it is all sealed up. when the windshield is installed.

Brian, an EAJ

diver don

Jul 31, 2007, 05:08 AM

Brian,
Thanks for the excellent report.

DD

pdemon

Jul 31, 2007, 08:43 AM

If you are going to power it with e-power, you might want to find a better way to install the windshield. The canopy is attached via 8 small sheet metal screws, multiple remove/install of the windshield to change battery might resulted in breaking the windshield. Also there is no air exchange from the cabin, it is all sealed up. when the windshield is installed.
Brian, an EAJ

A nice and scale solution could be removing the rear portion of the canopy (aft the second former). Real Challenger's pilots often leave the windows open or fly without. The front part could be secured with small powerful magnets...
Pierluigi

patrickegan

Jul 31, 2007, 10:04 AM

Any specific reasoning on the Aveox or just something you had laying around?

bhchan

Aug 01, 2007, 02:59 AM

Patrick

I just had the Aveox laying around, so I just going to use it, before the rust got to it!

Cutting the windshield to remove the back half is a good idea. with the center support open, the battery can be installed/removed without removing the windshield.

Attach some photos too.

Brian, an EAJ

patrickegan

Aug 04, 2007, 10:14 PM

JUst got mine, couple of holes in the elevator :(

bhchan

Aug 04, 2007, 11:22 PM

Patrick,

Yeah, the package of the stab was sitting next to the fuselage on my kit, the fittings for the strut rubbed against the stab, caused two major deprssions on the stab but no holes.

Send a message to Paul at KMP.ca, he is very good to deal with. I sent emails to Paul@KMP and one to HL, regarding the colorless(that is differs from the web photos on HL and KMP sites) issue and they should note that on their prospective web sites so there will be no supprise when the customers received theirs. Paul and I exchanged several emails and offer to do something for me about the color issue . I told him, white is fine with me, I like the cooler color anyway. I did not hear back from HL.

Did you get an all white one or one with blue trim?

Brian, an EAJ

patrickegan

Aug 05, 2007, 11:04 AM

No, I got blue and white but would have rather had all white. (There’s just no pleasing some people. :) )How you find drilling out the nose weight? The cutting the nose off looks interesting.

bhchan

Aug 05, 2007, 09:27 PM

Patrick,

I just use a big drill bit and go at it. Just be careful not to drill through the nose!

The lead is not that big is it, it is not form fitted, the center goes a tny bit deeper and the side has less and does not as big as the cavity.

The cut off nose may be the earlier version, that kit came with two nose and one is more rounded and one is not.

Brian, an EAJ

patrickegan

Aug 05, 2007, 10:45 PM

Big is relative Amigo, I’ve got a nice set of hole saws! :D

pdemon

Aug 06, 2007, 03:28 AM

Brian,
my compliments to you! I've found too difficult working in the tight fuse space with enough precision not to damage the thin fiberglass nose, so I gave up removing the lead with a drill.
A flexible drill shaft , and a lot of patience, would be a possible solution. I cutted the nose off with multiple strokes of a new big scalpel blade, that give a nice, thin and clean cut. I'm installing the tail surfaces at the moment...
Pierluigi

bhchan

Aug 06, 2007, 09:08 PM

I have a 12" long 1/4"(6mm) drill bit and a 12" 3/8"(9mm) drill bit. I just go at it with a electric drill and took about 2/3 of the lead out. I might have taken too much out!

Brian, an EAJ

bhchan

Aug 07, 2007, 12:20 PM

The plane looks like it was designed by committee... parts of it is over kill and parts of it is underbuilt. The front bulkhead and the rx battery holder are massive. The top cabin and wing support seem to be a little under size for me (thus my added carbon rods structure).

Brian, an EAJ

pdemon

Aug 09, 2007, 08:18 AM

I've just started the tail building sequence and noticed that the U shaped elevator halves joining wire is not glued in the the slots: please check yours before glueing the stab to the elevator! It would make sense to roughen the chromed wire to give the glue some grip.

patrickegan

Aug 09, 2007, 10:12 AM

pdemon,

Do you have a pic of the nose?

Brian,

Why too much?

bhchan

Aug 09, 2007, 11:55 AM

Brian,

Why too much?

Patrick,

Not sure,just a wild guest. I extended the tail so it might have to put some weight back, but I would use a bigger battery than carry dead weight.

Brian, an EAJ

pdemon

Aug 09, 2007, 04:43 PM

pdemon,

Do you have a pic of the nose?

There is a picture in the first page of this thread, if you need some more detail, just ask...
Pierluigi

bhchan

Aug 11, 2007, 03:29 AM

Warning: LOW temp film on C II.

I was working to glue the horizontal(Stab) to the vertical(fin). I try to iron down the covering after I cut the slot in the covering for the glue. I almsot melting the covering, it got loose and curled up. I was using the same setting on ultracoat( I was recovering the vertical fin with Red ultracoat). I have to lower the temp to about 250° to stop it from melting.

Brian, an EAJ

pdemon

Aug 11, 2007, 04:33 AM

Brian
strange enough... I have my iron set a tad under 340°F and have no problem in the same step! Maybe there are different covering in different production lots.
Seem we are having a parallel building session ;)
PG

bhchan

Aug 11, 2007, 04:39 AM

PG,

yes, may be. I have an all white version, may be that was a prototype for Hobby Lobby and they sold it to me.....

Brian, an EAJ

pdemon

Aug 12, 2007, 04:19 PM

Slowly progressing... Built the tailplane and glued to the fuse. I've made a variation on the instruction: I didn't use the struts to help positionig the stab relative to the wing tube, it was a messy job registering the struts' lenght, always too short or too long :( .
So I fixed the tailplane with 30' epoxy and a lot of masking tape, pulling the tape where required to obtain the right position. Than I screwed the struts to the fuse and the stab.
My friend Joe seems satisfied with the result and is eager to maiden the plane... :D

bhchan

Aug 12, 2007, 06:45 PM

That nose gear looks good. I might have to get one for my plane! Like the big cooling hole up front to let the cool air in for the battery and motor! What are you going to do there? Make it removable to change battery?? Hey that may is a good way to do it without getting the windshield off!

Brian, an EAJ

pdemon

Aug 13, 2007, 01:51 AM

Brian
I'm thinking about hinging the nose cone in the bottom of the opening to change batterie with ease, with a strong magnet to keep it closed.
I'm a little doubious about the built in side thrust of the motor: it seems a lot... Have you been able to keeep the prop in the longitudinal axis: it seems a little offset from the picture.
PG

bhchan

Aug 13, 2007, 12:08 PM

PG, I don't think you can, unless you offset the mounting base to put the prop at the center line. It seem too much to me too but it seem to fly in the video, will see. You can always put a wedge on the motor mount to reduce the side thrust. Most of my planes have 2° side and 2° down thrust.

The Wingo I have has zero side thrust.

Brian, an EAJ

pdemon

Aug 13, 2007, 01:06 PM

My overpowered Easy Star has no side thrust, and don't seems to need one!
Hope the guys at KMP know what they are doing :rolleyes: ...
Today report: hinged the ailerons and preparing the servos.

bhchan

Aug 13, 2007, 02:20 PM

PG,

Are you changing the struts attachment? I recovered the fin and rudder to RED. I ripped the covering when I tried to test fit the stab to the fin! :(

Also the stabilizer seems to be very LARGE and the FIN/Rudder is kind of SMALL.

Attached is a photo of the earlier version of the plane.

Brian, an EAJ

pdemon

Aug 13, 2007, 05:09 PM

Brian
not working on the struts yet, will keep you informed.
From the pictures seems that many improvement have been done on the model for its second release: different wing, wire landing gear, different struts, different fuse and wing seat... All in all a totally different model of the same airplane.
I decided not to modify the kit regarding dimensions and areas, being a scale model if it flies like its real counterpart, there should be no problems!
PG

patrickegan

Aug 13, 2007, 11:01 PM

I hope to get rolling on mine soon P

_helitron_

Aug 24, 2007, 03:09 PM

Hi guys,

in the meantime I've also ordered a Challenger II from Lindinger here in Austria and should have it on my workbench next week.

I'm curious if anyone with flight experience with the Challenger II already have tried to program flaperons. Am I right when I think I can slower the bird during landing approach with flaperons (both ailerons a bit down) ?

Cheers,

/Erwin

pdemon

Aug 24, 2007, 03:43 PM

Erwin
surely you can! That's what I plan to do with my Challenger. Maybe it is not possible to lower the ailerons too much ( as with flaps), in that case you can loose authority in roll control the moment you need it more...

In the meantime I've routed the ailerons wires through the wing and installed the connectors.

This time I experimented a new (for me at least) solution: a 7pin plug and socket from the electronic store. The bonus are: nice and firm plugging, very good electrical contact, bolted on socket in the fuselage.
Of course you don't need all the seven contacts, but they contribute to make the assembly stronger and in future it is possible to add some gadgets as landing lights... ;)
Ciao
Pierluigi

patrickegan

Aug 24, 2007, 04:01 PM

nice

bhchan

Aug 24, 2007, 05:25 PM

PG,

You can also route the antenna(aerial) through the wing connector and have the antenna out on the wing.

I installed the wing servos, using some full size servos. Drawback, since the servos lay on their side, you will need a extra long servo arms to get it pass the wing skin!

Brian, an EAJ

patrickegan

Aug 25, 2007, 01:49 AM

Brian,

Are you going to the fly in 8-25? P

bhchan

Aug 25, 2007, 02:55 AM

Patrick,

What 8-25? Where? Is it the Red Baron event? If it is, that is a bit far for me to go.

I plan on either going to Tomcat's Sept 8th and/or Lagoon Valley on 9-9.

Brian, an EAJ

bhchan

Aug 25, 2007, 03:10 AM

Tried to glue the tail on and found out the wing is not mounted to the fuselage correctly! :eek: :eek:

The joiner hole is off by 1/16" of an inch and the alignment pins are worst. I need to borrow an incident meter to measure if both wing have the same incident.

Also I am thinking to cut the nose off to make a battery hatch so i don't have to get the windshield off every time to access the battery. Cutting the rear part of the windscreen off is a good idea, but that is still to far to reach the front to connect the battery.

Brian, an EAJ

patrickegan

Aug 25, 2007, 09:32 AM

I did notice that things were not equal. I'll have to check that out but besides that I'm almost ready to fly. P

_helitron_

Aug 25, 2007, 01:46 PM

@Pierluigi
Thanks for your hints. Interesting connection system you choosed (DIN connector I assume). As a electronic developer since 30 years, I'd prefer a gold-plated connector and one with a locking mechanism.

@Patrick
I'm very curious already of your first flight impressions. In any case good luck for the maiden, for the other guys also of course :) !

Cheers,

//Erwin

pdemon

Aug 25, 2007, 04:25 PM

Erwin
yes, it's a Din connector. The contact surface of each pin is at least twice the surface of a normal rc servo plug pin, so I think I can pass on the lack of gold plating.
Consider also that the locking force of the couple plug-socket is very strong, so that I have to put some drops of contact cleaner oil that act as a lubricant and antioxidating agent in one product.
I'm currently installing the motor mount, pictures coming soon...
Pierluigi

bhchan

Aug 25, 2007, 05:08 PM

Erwin,

Just make sure you do not glue the plug onto the wing. This way if the wing separated a bit and the contact is still good.

Brian, an EAJ

patrickegan

Aug 25, 2007, 10:06 PM

Hopefully Monday...

bhchan

Aug 26, 2007, 01:21 AM

Mine would be a while longer before it can fly, I must have got a lemon-ish plane. I found more problems with mine.
I broken the half clevis for the tail support by just unbending it. Have to redesign the tail support. Not the wing strut are not even. They measured out the same length, but I guess the wing was not mounted correctly, The struts one side are too long and the other side are not quite long enough! More works! So much for ARF!

Brian, an EAJ

_helitron_

Aug 26, 2007, 02:22 AM

Erwin,

Just make sure you do not glue the plug onto the wing. This way if the wing separated a bit and the contact is still good.

Brian, an EAJ

Thanks for the hint, Brian :) !

Cheers,

//Erwin

_helitron_

Aug 26, 2007, 03:02 AM

Hi Pierluigi,

Erwin
yes, it's a Din connector. The contact surface of each pin is at least twice the surface of a normal rc servo plug pin, so I think I can pass on the lack of gold plating.
Thinking in this way you're right of course. It's way better as a standard servo plug for sure.

Consider also that the locking force of the couple plug-socket is very strong, so that I have to put some drops of contact cleaner oil that act as a lubricant and antioxidating agent in one product.
Agreed, should be a secure connection so far.

I'm currently installing the motor mount, pictures coming soon...
Pierluigi

I'm already curious again of the next pics :) ! Thanks for sharing it.

By the way, what type of powerplant have you decided to use ? And which prop ?

I decided to install a Hacker A30-10XL together with a Hacker X-70 SB pro ESC and an Aeronaut 3-blade 10x6 folding prop with the appropriate 3-blade spinner (Mike mentioned this stuff already in one of the first posts in this thread).

As you I've also decided to install bigger wheels as I've also to start mostly from grassy runways. In the moment I'm still lurking around for the right wheels.

Cheers + a nice sunday,

//Erwin

_helitron_

Aug 26, 2007, 03:08 AM

Thanks for sharing the pics Brian !

I don't like such long and thin metal rods very much and I think I'll replace it with carbon tubes and ball links on both ends as I know it from my helis.

Cheers + a nice sunday,

//Erwin

_helitron_

Aug 27, 2007, 01:13 PM

Just a little update, Challenger II kit arrived my workbench today in good condition :D ! On the pic for comparision a T-REX 450SE heli.

First I've to search now for bigger wheels as Pierluigi did.

Cheers,

//Erwin

_helitron_

Aug 29, 2007, 06:05 AM

Don

We recently did an E-conversion for this plane at Hobby Lobby, below is our setup. We will have video of this up shortly, but this system works beautifully and will fly the plane very well for over 10 minutes. One of the keys to this working so well is the Aeronaut 3 bladed prop. It is a folding prop but we locked down the blades. The 1" prop that we are running is just about a large as this plane can use.

1 PM282612 AXI 2826/12
1 PM282002 Radial Mount
1 SPIN44 44A Jeti SPIN
4 HTS322 HS-322 Servos
1 RCD120 Electron 6
1 RCDXT_ _ Crystal
2 HT0604 12" HD Servo ext.
1 HLAN5525 40mm 3-blade spinner
1 HLAN4232 3-Blade Middlepart
2 HLAN3428 10x6 Prop Blades
1 DEA1300 Deans Ultra
1 FMAC03S Series Connector
2 PQ50002 2 Cell Lipo Packs
1 GR3389 2.5mm wire
1 AMM111 SPACER SET

Have fun,

Mike Hines

Hi Mike,

I hope you're still watching this thread.

Would you please be so kind and explain a bit or post a pic where you've located the LiPo in the Challenger respectively how much lead have you removed out of the nose to get the right CG.

Perhaps additionally how and where your AXI motor is mounted exactly.

Thanks in advance !

Cheers,

//Erwin

_helitron_

Aug 29, 2007, 07:08 PM

First pic with powerplant, 400W, 11x8 3-bladed folding prop :) !

Planned LiPo 3S3P 9600mAh :eek: , three times of this here https://www.unitedhobbies.com/UNITEDHOBBIES/store/uh_viewItem.asp?idProduct=4889

Decided to remove all the lead in the nose, I hate unnecessary weight.

Cheers,

//Erwin

bhchan

Aug 29, 2007, 08:37 PM

Erwin,

I don't know why they recommend that prop, the Graupner 10x7 or 10x8 3 blade works just as well and about 25% of the price. I am using a Graupner 11x7 two blade on 4S2p 4300 mah. I like that spring loaded nose gear, is that not too tall compare to the main landing gear?

Brian, an EAJ

patrickegan

Aug 29, 2007, 10:05 PM

I tried to maiden mine this morning. I’m at about 10Lbs AUW on a master airscrew 3 blade, 11 x 7, 4S eflight 32 combo. I didn’t make it off the ground, drilling out nose weight with a 1 3/8” spade bit. I’m down about 5 oz’s thus far. Switching to an APC 11 x 8.5 taking out all unnecessary weight for a test flight in the morning.

_helitron_

Aug 30, 2007, 01:09 AM

Hi guys,

here a pic of my "tuned" landing gear parts.

Height of front gear is ok I think, don't forget the bigger wheels, Brian. Additionally positive incident is good for take off of course.

Reason for choosing the Aeronaut prop explained Mike here

http://www.rcgroups.com/forums/showpost.php?p=7847715&postcount=9

Good luck for maiden, Patrick :) ! I'm very curious ...

Cheers,

//Erwin

bhchan

Aug 30, 2007, 01:30 AM

Erwin,

I have been using the Graupner Grey Nylon for a long time. I think these are much better prop than they think. I like them a lot, specially for electric. Yes, the CAM prop is probably better for the lower power range, the Grey Super Nylon are good for higher power application.

Patrick,

Yours is 10 pound? Where is the extra 1.5 pounds came from? Hobby Lobby claimed theirs is only 8.something pounds!! They also claimed they did not take the lead out and move the battery back for balance! Was it lack of speed? Sorry I have to ask a stupid question, is the propeller on correctly? It is a pusher, so the label on the prop should face forward.

Brian, an EAJ

patrickegan

Aug 30, 2007, 01:36 AM

Downlink, camera and various telemetry equipment.

_helitron_

Aug 30, 2007, 01:38 AM

Thanks for the prop hint, Brian !

//Erwin

patrickegan

Aug 30, 2007, 01:43 AM

I don’t think the Master airscrew is putting out the thrust at what could be considered low RPM’s. $85 bones for the hobby lobby 3 blade set up seems a bit steep!!! The two blade APC 11 x 10 appears to be as robust or better. I’m going for it in the a.m. so we’ll see. P

bhchan

Aug 30, 2007, 02:09 AM

Patrick,

Go to RC Country and get a Graupner Super Grey Nylon 11x7 and see, that should set you back about 10.00. Or you can try 10x8 3 blade, if they have it.

Brian, an EAJ

_helitron_

Aug 30, 2007, 05:55 PM

Challenger II first time on her own feet :) !

Cheers,

//Erwin

pda4you

Aug 30, 2007, 07:46 PM

Guys thought I would chime in....

Mine is done and few last night. I am doing the review for eZone, but will share with you my observations and thoughts here - the review will be done in the next few weeks and you can get all my thoughts.

Don't worry about the lead - I too hate the weight - but it would be a pain to remove - it flies fine with it - AUW 8lbs on the nose for me (with the 4s 5000 packs).

You will NOT get it off the ground if you don't change a couple of things (at least I could not). You MUST have a positive wing AOA and a more rearward CG and it helps to add upthrust.

I use a much longer nose strut with 4 degrees or so of positive wing incidence. Hobby Lobby splayed their main gear out - to accomplish the same thing.

It needs upthrust - surprising KMP did not get that they got the left thrust OK.

I am using a APC-e 11x7 prop for 500w and ~34amps - it flies well with this power - and in fact more power may get you in trouble. As all high thrust line planes - it noses down with power application (more upthrust likely would help).

I have attached some pics- I put the batteries (right under the CG with no nose weight removed) and am still moving those back and it is flying better and better. I "cut" the rear door out - on both sides - and just leave it open - it works great (my 15 year old sons idea!!!! :) )..

Mine too was all white - Hobby Lobby is looking into that.

Let me know what questions you have....

Mike

pda4you

Aug 30, 2007, 07:51 PM

Another quick note - I have tried the MAS 11x7x3 and liked the 11x7 APC -e a lot better.....

I have not flown with the Aeronaut CAM prop yet - but will try it too.....

Mike

_helitron_

Aug 30, 2007, 08:00 PM

Wow, great Mike !

Very nice bird and thanks for sharing the excellent pics and for the very usefull hints !

Ah, yes, may I ask you to post a pic of the inner side of the nose ? I'm curious how you've managed the control rod for the steering wheel. Secondly what flight time do you estimate with this 5000mAh battery ? Thanks in advance.

Edit: the Aeronaut CAM props are one of the best you can buy for sure because they are designed by Rudi Freudenthaler, the multiple electric world champion from Austria.

Cheers,

//Erwin

patrickegan

Aug 30, 2007, 09:26 PM

I didn't try this morning as I'm taking the day off

pda4you

Aug 30, 2007, 09:26 PM

The nose gear steering was pretty standard - but needs to come off of the same side of the servo as the rudder servo so the linkage is fairly straight. I used an EZ type connector and a solid rod on with a clevis attached to the steering arm end....

But it is WAY sensitive in steering - I need a longer arm on the nose gear to decrease the sensitivity...

It is a fun airplane!

Mike

bhchan

Aug 30, 2007, 10:11 PM

I usually put steering with anther servo and mix it with the rudder. On the Fut 9C, I can put the steering on a knob(Ch 7)for centering and mix with the rudder ch for steering. Also I can vary the mix rate using the throttle stick position. Low mix rate at high throttle and high mix rate at low throttle.

Also one thing about pusher, the wing is not working until you have enough ground speed to rotate. It is not like a tractor, the propeller blasts the air over the wing regardless of ground speed.

I still need to borrow an incident meter to check the incident of each wing. My cruel "rubber band a arrow shaft under each wing method" showed they are not the same.

Mike,

How much more up thrust did you put in? I see you use master airscrew, I think those may not be the best prop around!

Thanks for the preview.

Brian, an EAJ

Arck

Aug 31, 2007, 01:03 AM

HI guys, Im into electric too but in this case I will fly this bird in glow version, I think all the buildings tips are the same and we have the same problems with the plane, as you see the plane has too much left trust, did you correct this to zero degrees? or you install the motor with the design trust, I think is to much,,

bhchan

Aug 31, 2007, 03:18 AM

Arck,

The way you shim the motor mount, it will not change the thrust angle.

Brian, an EAJ

_helitron_

Aug 31, 2007, 07:19 AM

pda4you

Aug 31, 2007, 09:04 AM

Mike,

How much more up thrust did you put in? I see you use master airscrew, I think those may not be the best prop around!

I have used the MAS and hate it - per my post above the APC-e 11x7 is what I like....lower draw and more thrust (typical of my experience with MAS)....

I used about 1.5 degrees or so of up thrust - it was two washers on the bottom lug and 1 on the middle ones. So not a lot - it could use more. I need to get some more flight time on it....

Also one thing about pusher, the wing is not working until you have enough ground speed to rotate. It is not like a tractor, the propeller blasts the air over the wing regardless of ground speed.

Brian it was the oddest thing ever - I was going across the ground at 50+ MPH (not exaggerating) and the plane with full up would NOT rotate. I talked to Hobby Lobby about this - they had the same issue and had to also use the positive incidence. Look at their site video you can see it is really cooking when it rotates!

I still need to borrow an incident meter to check the incident of each wing. My cruel "rubber band a arrow shaft under each wing method" showed they are not the same.

Yikes!!!! I must admit - I did not check mine - and it flew with zero trim - except elevator (need lots of up - indicating the CG was off). I am still getting it dialed in however.....I know Hobby Lobby has their battery far aft of where mine now sits.

That likely was an issue with my rotation as well.....

Mike

pda4you

Aug 31, 2007, 09:06 AM

Arck,

The way you shim the motor mount, it will not change the thrust angle.

Brian, an EAJ

Yep - you need to mount the top of the mount against the fuse and shim out the bottom of the mount for the proper up thrust.

as you see the plane has too much left trust

Maybe a touch - but DO NOT take it all out. In fact I left all of mine exactly as they have it and I feel it is just about right..... Remember it pushes the nose right and that is needed.....

Mike

Arck

Aug 31, 2007, 09:18 AM

Arck,

The way you shim the motor mount, it will not change the thrust angle.

Brian, an EAJ
Thanks, I twist the motor a little only for muffler clearance, but although I put a lot of washers it seems left trust,,,,my question goes if this plane needs left trust? the plane was built in that, all my electric planes has zero trust, (v diamond, xxl su27, fan trainer,,,,),,,
Thanks

pda4you

Aug 31, 2007, 09:24 AM

my question goes if this plane needs left trust?

Yes it does....see above - we were posting at the same time!

I offsest my electric motor so the shaft was centered - I don't think you have that as much of an option with the glow with the larger mounts.

MIke

Arck

Aug 31, 2007, 02:07 PM

Yes it does....see above - we were posting at the same time!

I offsest my electric motor so the shaft was centered - I don't think you have that as much of an option with the glow with the larger mounts.

MIke

Thanks,,,10 deg ?, I think is too much, the engine will push the plane from the side, maybe 1.5 or 2,,,,please, Im incorrect?, tell me if its wrong,,,,

pda4you

Aug 31, 2007, 02:12 PM

Thanks,,,10 deg ?, I think is too much, the engine will push the plane from the side, maybe 1.5 or 2,,,,please if Im incorrect tell me its wrong,,,,

I was amazed, but it was pretty close - zero rudder trim, zero aileron - for me.....

I agree it look excessive. Let me know what you think but I left all mine in - as did the gang at Hobby Lobby.....

It FOR SURE needs upthrust - still getting that dialed in. More flights tomorrow.

Mike

bhchan

Aug 31, 2007, 02:38 PM

Hi Brian,

as you I've also planned to remove the lead in the nose. Have you already checked where you must mount the LiPo then ? In the nose ? When yes, would you please post a pic of your battery mount ? Thanks.

//Erwin

I have not put mine altogether yet, I will try to find out where si the CG and then determine whether I cau the nose off or not. If the battery end up in the nose, I would cut the nose off, ala PG's. Use that to put the battery in through the nose. No messing with the window.

I will add some up thrust too.

Brian, an EAJ

_helitron_

Aug 31, 2007, 03:55 PM

Arck

Aug 31, 2007, 11:11 PM

I was amazed, but it was pretty close - zero rudder trim, zero aileron - for me.....

I agree it look excessive. Let me know what you think but I left all mine in - as did the gang at Hobby Lobby.....

It FOR SURE needs upthrust - still getting that dialed in. More flights tomorrow.

Mike
Ok, Mike I will give KPM designer a try, will let the motor left trust and as you say a little up thrust, Im continuing with he building, soon will us compare both performance glow and electric,
Here is the video of the construction of the full scale challenger, what a pretty plane,,,
http://youtube.com/watch?v=c6ny5ts2lVk
Thanks for your advices,,,
wm

_helitron_

Sep 01, 2007, 07:44 AM

Thanks a lot for the link Arck, great vid !

//Erwin

_helitron_

Sep 01, 2007, 07:48 AM

I have not put mine altogether yet, I will try to find out where si the CG and then determine whether I cau the nose off or not. If the battery end up in the nose, I would cut the nose off, ala PG's. Use that to put the battery in through the nose. No messing with the window.

I will add some up thrust too.

Brian, an EAJ

Thanks Brian ! If you really cut the nose I'm very curious how you manage this practically (I read how PG did it) and later then the reattachment of the nose to the fuzz and the closing mechanism.

Btw. I'll also add some degrees uptrust as adviced, additionally I just make my special front gear (pic on page 5) a bit longer to have generally more positive incidence during takeoff.

Would anyone with a finished Challenger please post a pic of the inner side of the nose respectively of the steering mechanism ? Thanks.

//Erwin

patrickegan

Sep 01, 2007, 11:05 AM

I took about 7 ozs of lead out of the nose, any more and I'd have a hard time with balance.

pda4you

Sep 01, 2007, 01:18 PM

Nose gear pic - the nose is TOO sensitive - I am making a longer nose wire arm as we speak....

Mike

_helitron_

Sep 01, 2007, 02:44 PM

Great, thanks Mike :) !

//Erwin

_helitron_

Sep 03, 2007, 07:03 AM

Hi guys,

would anyone please be so kind and post a pic of the inside of the fuselage behind the servos with batteries installed ? Thanks.

And what's the biggest battery weight you've installed so far ?

My planned batteries have a weight of 1080 grams (4S3P 9600 mAh for a long flight time) that's the reason why I try to remove the complete lead from the nose. I'm just in progress to do this, horrible job at all :( !

//Erwin

pdemon

Sep 03, 2007, 09:32 AM

Hi all
I'm back on this project...
Here you can see the motor mount, the motor and the 10" Ramoser Vario Prop, a variable, only on the ground- unfortunately!-, pitch prop, .

The motor comes from United Hobbies and is a KD 36-12XL: for the price I think it's worth a try!
http://unitedhobbies.com/UNITEDHOBBIES/store/uh_viewItem.asp?idProduct=4657

You can also see the adjustable motor mount is regulated to counteract a bit the side thrust and permit the upthrust to be adjusted too.
PG

_helitron_

Sep 03, 2007, 09:38 AM