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Posted by dhc8guru | Feb 14, 2012 @ 08:51 PM | 2,214 Views
Testing the Citabria

TDaerodesigns Citabria testing (1 min 36 sec)


If your interested in building one, plans can be found on this thread

http://www.rcgroups.com/forums/showthread.php?t=1548724
Posted by dhc8guru | Jan 10, 2012 @ 07:28 AM | 2,461 Views
For the past year, I have been focusing on my aircraft design. I decided to pull out the heli's for a little break the other day. first on the chopping block was my HK 450 Pro. All went well for a few flights until something let loose in the tail while starting a tic tock and it did a blindly fast piro into the dirt....totaled.
Pulled out the Trex 450. After a few flights of tweaking the set up and getting back in the saddle, I was flying and pulling moves I had only tried on the sim.
I was amazed! I guess walking away from it for a long period of time was what I needed to regroup.
Posted by dhc8guru | Dec 14, 2011 @ 05:51 PM | 2,707 Views
Sorry for the poor video quality. The batteries went dead in my video camera so my wife shot the video on her phone. I didn't think I would get a chance to fly the plane indoors till this weekend but the rain and wind stopped.

Scratchbuilt, foam PC6 Porter RC airplane (1 min 16 sec)


...Continue Reading
Posted by dhc8guru | Dec 14, 2011 @ 01:34 PM | 2,773 Views
I tossed this together this week. I wanted another plane for indoor flying. I just got a quick flight in the front yard and it seems to fly fine. it may need an extra couple of inches on the wing to make it more indoor friendly. I am still kicking around the looks of it. Too me a Porter can be hard to get proportionally correct and look right.
A good chunk of the fuselage was milled out to lighten the plane. Without electronics, it weighed in at 1.4oz(about as much as the battery)

WS 28"
Length 24"
5oz flying weight.

HK Park 250 W/ 6 X 4 prop
Nanotech 2s 460mah lipo
Posted by dhc8guru | Dec 12, 2011 @ 07:24 PM | 2,578 Views
I have been thinking about designing an easy to build 3 channel airplane for some indoor flying. Since I love the Pilatus PC6, I figured it would be a good candidate. There are a lot of scratch built 3channel planes and plans available but I want something that looks a little more scale and is lighter than what is available.
Keep you posted to what I come up with.
Posted by dhc8guru | Dec 04, 2011 @ 06:03 PM | 2,538 Views
With the poor weather putting a dampener on getting out for some flying, I decided to build a modified M7. I also wanted to finish one complete with covering and some graphics.
I refitted the original symmetrical wing that I started with when I began designing this plane. I decided not to use this wing only because it was a bit more touchy to fly. This wing has two inches clipped off the wingspan. I lightened the wings by milling pockets to improve the roll rate and also to help offset the weight of adding covering to the plane.
This is the final product. I will test fly it later this week.
Posted by dhc8guru | Dec 01, 2011 @ 09:38 AM | 3,142 Views
I posted in the foam aircraft scratch built section the plans, build manual and a drawing for download.

Happy Holidays!
Posted by dhc8guru | Dec 01, 2011 @ 06:04 AM | 3,094 Views
Five hours spent flying and shooting the bull at the field yesterday. Forecasted wind,rain the rest of the week. I figured I better get in all the flying I could.
Posted by dhc8guru | Nov 27, 2011 @ 09:42 PM | 2,586 Views
Its hard to beat the Phlatprinter when it comes to cutting foam.
Here is a video of the Citabria being cut.

Phlatprinter cutting an RC foam indoor airplane (2 min 26 sec)

Posted by dhc8guru | Nov 27, 2011 @ 09:00 PM | 3,367 Views
With the poor weather that has been hitting us lately, I decided I would do some indoor flying. So, I went ahead and whipped up this little Citabria.
3mm depron construction
34" inch wingspan
5.4 oz flying weight with a 2S 460mah lipo
I will see how well it fly's this next weekend and make any necessary changes.
Will probably post some free plans in the scratch built section if it turns out to be a good flyer.
Posted by dhc8guru | Nov 27, 2011 @ 02:38 PM | 3,231 Views
Get an extra 10% off and free shipping on the Skywagon kit on cyber Monday!
Posted by dhc8guru | Nov 25, 2011 @ 11:49 PM | 5,297 Views
I got this motor http://www.hobbyking.com/hobbyking/s...dProduct=18113
And put it in the mini M7. What a blast! Running on 2s lipo's it is a power house. Well atleast i thought it was till today at the field, I forgot my 2s pack but had some 3s packs. Since I wanted to get some test flights in, I went ahead and used the 3s packs. running with 3s packs, this motor is completely out of control!
Anyways, I fellow flyer was having way to much fun and ended up getting a little to close to the ground, tried to pull out of it a little to hard and ended up snapping the wing. No other damage occured. It was actually pretty amazing it was even holding up for as hard as he was pushing it prior to the crash. A little gorilla glue and it s good to go. I went ahead and installed a .121x.040 flat carbon fiber bar in the wing and a 2" strip of strapping tape on the top and bottom of the wing. Definitely overkill but I figured it would keep it from happening again. Definitely not needed for typical aerobatics because I haven't had any problems until today.
I am pleased with the design and have no plans for any more changes.
Posted by dhc8guru | Nov 19, 2011 @ 10:39 AM | 2,692 Views
I need to come up with a name for this plane. Any suggestions?
This is the redesigned fuselage. In the photo you can see in the upper right corner of the battery box, I beefed up the fuselage with a milled truss, that also acts to hold the battery in place and add some protection. This truss is for reducing torsional twisting and absorb harsh shocks on the nose gear.
I upgraded the motors. I am using two Atlas 2312/07. This motor is great at swinging a large prop with low amp draw. They are not super powerful but very efficient. The two motors are equipped with 9X6 props. Noted the recommended props are 10X7 - 11X7. Unfortunately I don't have the ground clearance. The combined power output is 137 watts and 12.7 amps. The plane weighs 24oz with a 2200 3 lipo.
So that gives 91 watts per pound. More than enough, especially considering the wing loading is 14.4 oz per sq/ft.
I will test fly it tomorrow.
I don't really have the time to start any new airplane designs. I am still testing some mods on the Mini M7. The handling characteristics of the plane are great for outdoor flying but I need to tweak it. Just need to put some focus into it.
Posted by dhc8guru | Nov 13, 2011 @ 09:05 AM | 2,856 Views
I decided to start selling a bare bones Skywagon kit. The kit is for those who have already bought the full kit and need a replacement airframe or for those who have the materials and tools to make accessory components and would just like the airframe.

The bare bones kit includes:
Fuselage set
wing set
tail set

$25
Posted by dhc8guru | Nov 12, 2011 @ 08:12 PM | 3,011 Views
I put the new twin into the dirt yesterday. Inverted, windy and low to the ground...amazing how that tall grass can reach out, grab the plane and crash it. only the fuselage was damage and I could have completely repaired the damage but I would rather start over fresh.

I usually pile a prototype into the ground to see how well it fares. So this was actually a good thing. I found a few weak spots that should have fared better. Of course I don't expect it to fly away unscathed but I expect a certain percentage of it to survive. No biggie, some easy redesign.

Happy flying!
Posted by dhc8guru | Nov 04, 2011 @ 09:08 PM | 2,826 Views
Since my last update, the changes that I last wrote about were incorporated and I got a test flight in. I am feeling the design is solid but I am interested in cutting the wing span down by two inches to see what effect it will have on it. I took it out last Sunday and it was flying very squirly. I found the rudder servo wasn't recentering well. The rudder is extremely effective, so even the slightest unwanted deflection can become a problem. I will probably reduce the size of the rudder. After that, I will turn it over to a couple of guys at the field for their opinion before I release it as a kit.
Posted by dhc8guru | Nov 04, 2011 @ 04:32 PM | 2,720 Views
I didn't have a second person to film the first few flights of the new twin motor design, but I did have my key fob camera to take an on board video.This video is of the second flight, I didn't want to risk losing the camera if something went wrong. All was good.
The plane flew great! Better than I expected being my first twin motor design.
Changes: I need to take out some of the motor down thrust.
I was about 3/4" (forward)off on my CG calculation. Usually my calculations are within a 1/4", so I was able to remove the nose weight. I have already redesigned the changes I wanted to make to the fuselage earlier today. Mostly with component placement and some nose gear changes.

Update I removed the wing set from the original fuselage in preparation for the new one. I will program the G-code tommarow and cut the new fuselage I may try to find some more areas to reduce weight from the airframe. Every bit counts as I may try using it for some FPV work in the future. I also increased the rudder size slightly for better feel. The design process is slow and time consuming. Minor changes have a major effect, so I avoid doing too much at one time. The handling characteristics of the Twin prototype are very solid, so luckily this plane will require little to make it the way I want it.

Scratch built twin motor RC airplane (3 min 19 sec)

Posted by dhc8guru | Nov 03, 2011 @ 09:41 PM | 3,001 Views
I managed to get the Twin Wagon finished. I ended up putting 1oz of weight in the nose to get the desired CG. I can easily do some redesign so the extra weight in nose won't be necessary. When it was all said and done, with a 1000 mah battery, the plane weighed in at 17.4 oz.
If I hold the plane vertical and throw the coals to it, the two blue wonder motors with 7X4 props will pull the plane out of my hands. So, it definitely will have some speed in the air. I left off the nacelle cowls the cover the sides of the motor. I figured I would wait for the next prototype before adding in all the final touches.
Posted by dhc8guru | Nov 02, 2011 @ 07:49 PM | 3,703 Views
I managed to get most of the airframe completed today. I only found a couple of small issues that need to be addressed, but nothing major.
I did add in a carbon spar to beef up the wing. Hoping to get it completed by the weekend for a test flight.

Some basic spec's
Wingspan 40"
Length 32"
Wing area 240 sq inches
If I use a monster 2200 3S lipo, it looks like the flying weight will be 18 oz. That should give it about an hour of flight time. LOL!
That will give a wing loading of 10.8 oz/sq. ft. I think a little weight to load up the wings will be a good thing with this plane.
Posted by dhc8guru | Nov 01, 2011 @ 09:36 PM | 2,880 Views
I sat down today to work on the design details of the Twin Wagon. I will write the G-code tommarow and begin making a prototype. I am not sure if there will be enough interest in the plane to justify production. Since I have never designed a twin engine plane, I wouldlike to at least do one for my own personal experience. I will post photo's as the plane gets built.
I dumb thumbed a rolling circle while flying the Skywagon on Sunday, so now I need to build its replacement.