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        Discussion Baby DR-1 cartoon fattie (now with a video)

#1 Rusty-Gunn Sep 02, 2008 02:11 AM

Baby DR-1 cartoon fattie (now with a video)
 
7 Attachment(s)
Otay, here is a new cartoon fattie I've been waiting to fly for several months now (prototype flew in the spring, months earlier yet). There was always something wrong when it comes to trying to maiden this plane - mostly bad weather, a few mechanical problems, borrowed ESC, etc.
Well, we gave it a go a few weeks ago, but it had ugly problems with wanting to fly "tail heavy" even when it was balanced. My belief is that I built-in way too much incidence in the main wing set, which makes it want to climb. After "landing" in the water, I set in more down elevator at the horn to compensate, and had to wait again. Weeks past by.
Yesterday we flew this plane, and it seemed to be the same, too much upwards flight (it could hover with the best of them, so maybe I should not complain :D ). Problem was I set the Tx trimming switch the wrong dang way! I mistakingly added more up elevator, causing my own problems. It did crash though, tossing free one of the wheels, and shaking loose the gear set too. After fixing the top wing we went out today to fly it again sans landing gear, and yet another problem arose. The rudder horn set-screw was loose, and it did not have rudder control in flight (it did have rudder control on the ground, though), so I set the plane down and we'll have another go another time.
I plan to post free plans for this one soon I hope at www.rcscratchbuilders.com. It all depends if I can prove to myself that this one will fly proper. Funny thing is, the original prototype did fly well, very well in fact, but this one is jinxed - it hates me. It might have something to do with the two inches I added to her fuselage in Number Two. She wanted to be short, fat and cute, I think, so she's punishing me. Planes are funny this way. Or maybe I need to get out more, suffering from cabin fever several months early... :D

#2 spudandcat Sep 02, 2008 02:46 AM

That is super cute!! i like it , thanks for yer efforts :)

spud

#3 Rusty-Gunn Sep 02, 2008 03:10 AM

Quote:

Originally Posted by spudandcat
That is super cute!! i like it , thanks for yer efforts :)

spud

Thanks. The Fokker Dr-1 has been a favorite all my life (who hasn't heard of the Red Baron?), and cartoon fattie foamies is a passion, as well, so I decided to combine the two, and see what happens.
I'm hoping the weather will be nice enough tomorrow to try again. I'm confident I can make this plane fly as well as the original, I just got to work out the bugs.
BTW I do have a more scale DR-1 foamie I'm working on as well. Its on the list of planes to finish.

#4 spudandcat Sep 02, 2008 04:18 AM

eagerly awaiting the plans ;)

thanks spud

#5 Jasta_66 Sep 02, 2008 05:41 AM

Rusty, I have found that there is often a fine line between "flies like crap", and "flies great" when experimenting with prototype aircraft. The difficulty is sometimes in identifying what is causing the problem. The fixing itself is usually easy.
CG is always first to look at. Then wing incidence, then motor thrust angle.
Alot of times, if I can just get a squirrly model up high enough to kill the power and let it glide for a few seconds, I can usually diagnose the troubles.

On a Bibe or Tripe like you have , and the rising problem you describe, I would first fool with the CG. These short nosed planes can be a bear to balance. Maybe you need a lil more weight up there..?? Then take a long look at the incidence of the top two wings. Too much could be causing the rising, like you said.

Good luck!

Jasta

#6 H2o Buffalo Sep 02, 2008 10:32 AM

Your plane Looks GREAT,but to fix the tail heavy problem you can extend the tail a few inches, longer bodies are definately more stable and I think this will not take too much away from the cool cartoony look.

Take a look at some of the 3d foamies and you will notice that nearly all of the biplanes have long fusilage(sp?) :rolleyes: and they are all quiet stable.

Good luck, and if you get good results, perhaps you might consider posting the pdf plans for others to build ;)

#7 Rusty-Gunn Sep 02, 2008 10:34 AM

Jasta.... thanks for the info. The battery compartment is right behind the firewall. I already extended the nose an inch as compared to the original, and the original flew awesome with the same batt I'm using. I did this to make balancing easier.
I think I may have used too much incidence on the wing set, and with such a short plane, makes the plane want to climb. I've gotten the plane high, but have not cut power yet. I was fighting the elevator/rudder issues, trying to land in one piece. Luckily, no serious damage so far.
I do have another, shorter (like the original) foamie available, and will put it together and see how it flies, too. Sometimes I think I should have left well-enough alone.

#8 TJC Sep 02, 2008 02:22 PM

Rusty,

I loved this one first time around. Hope you get it sorted. Like Jasta says the difference between a good one and a bad one is often something really small and easy to fix.

#9 Rusty-Gunn Sep 02, 2008 07:51 PM

If this one fails, then i've got a back-up fuselage and wing set ready to be put together. This one is two inches shorter then the one now. the original was short, and flew very well. It got jinxed when I lengthened the fuselage a few inches.

#10 Rusty-Gunn Sep 02, 2008 07:54 PM

Quote:

Originally Posted by TJC
Rusty,

I loved this one first time around. Hope you get it sorted. Like Jasta says the difference between a good one and a bad one is often something really small and easy to fix.

Just to clarify, and not confuse you (my bad!) this is not the one I made for the contest the other year, this is a new design. I keep messing with plans for the Dr-1 on occasion, its a favorite of mine.

#11 TJC Sep 02, 2008 09:45 PM

Sorry Rusty! New, old, modified or re-invented. Its still just too cute. :D

#12 Rusty-Gunn Sep 03, 2008 12:16 AM

Wow, dudes! This baby flies! We went out to fly three planes today (this one, the SR-71 and Jay-Jay), and it flies well. It needed a bit of right rudder and still could use a bit more (Nic flew it, and says he ran out of Tx trimming, so I'll re-adjust it at the horn for the next flight.
It did need down elevator at the horn, so I'll make sure to fix the problem on the plans.
I don't have pics, but do have video of this flight, which I'll post soon.

#13 jkarnacki Sep 03, 2008 12:25 AM

Hey Rusty, did you fly the jay jay with the EDF or prop in slot? How's it fly?

- Jeff

#14 Rusty-Gunn Sep 03, 2008 12:32 AM

Quote:

Originally Posted by jkarnacki
Hey Rusty, did you fly the jay jay with the EDF or prop in slot? How's it fly?

- Jeff

EDF. Check the Jay-Jay thread for an update. It flew, but needs more fine tuning.

#15 Rusty-Gunn Sep 03, 2008 01:30 AM

Here is a vid of the Baby DR-1 cartoon fattie. You'll notice it rocks left and right. This is a bit sensitive in the rudder area, but can be mended via computer radio, or as I did, at the horn. This model needed some up elevator to compensate for a design flaw, but I will have this fixed before I release the plans. We'll fly it again, and add more pics, and vids.
Baby DR-1 cartoon fattie (1 min 21 sec)


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