Posts: 146
Joined: 9/5/2006 From: Ottawa,
ON, CANADA Status: offline
Greetings Aurora lovers, I'm an ex-FAI pattern flyer whose been out of RC for approx 8 years. The last while I've been following the progress made on the electric power side of things and I've finally decided to take the plunge and build something "old school" (but fun) and go out and bore holes in the sky. Who knows....maybe I'll eventually catch the competitive bug again.
Why the Aurora? I've been a long-time fan of this design although I never had one. PTXMan in Calgary gave me a set of plans about 10+ years ago but I never did get around to building it. I did however build and fly Naruke's predecessor airplane, the Cosmos and really enjoyed it....that thing was a ballistic flying bomb!! Webra Race .61 (with a Perry pump embedded withing the backplate) up front coupled to a Hatori pipe. My Aurora will be built 99% as per my MK plans (fuse/wing profile, wing area, etc) although I'm going to incorporate a few different things that won't be so obvious at a glance. I'll be going the plug-in wing and stab route vice the standard 1 piece that the original design has. After flying 2 Piorun Eclipses and then 2 of Greg Marsden's Legend IIIs (both designs have plug-in wings/stabs), I simply find it easier to dial-in all flying surfaces (wings and stabs) both during the building/alignment stages and more importantly later during the flight trimming stage. Ref wing airfoil, I'll also be using a slightly thinner NACA airfoil with the high point 35% back. I'll incorporate the normal wing fillets on the fuse which will hide the fact that the wings are plug-in. I'm still undecided about trike or tail-dragger. Trike config is of course prefered from a purist point of view but I'm having trouble locating suitable mechanical trike retracts......can anyone help here?...a set of MKs would be ideal. I obtained my Aurora cowling and canopy from Singapore Hobbies. Great service from Ronald, their sales rep. The parts arrived in less than 2 weeks! Ron mentioned that my Aurora 60 cowling was their last one and that they will not be receiving any more. I hope he's incorrect on that one. As you can see from the attached photos, I'm well on my way on the project. The toughest part thus far was reproducing the required accurate ply and lite-ply bulkheads. My MK plans have sufficient fuse cross section views but about half of them don't correspond with the position along the fuse where the bulkheads reside. I was left with having to carefully study the plans, extrapolate measurements etc...I'm sure most of you have experienced the same thing scratch building. Another complicating factor was the fact that I had covered the plans in map-tack years ago with some resultant winkles here and there. Again, I was having to take my time. If anyone has a good set of Aurora plans (or a copy) they'd part with, I'll gladly pay for them.
My fuselage jig was simple in design but sufficiently effective. This coupled with my using a pool table as my work bench top ensured a true reference building surface. That same table top will be very handy when I later frame the flying surface to the fuse. I will be using good old fashioned squares and rulers for the alignment process, vice incidence measuring tools/meters which I find difficult to get the same readings from them twice in a row.
Anyway, I won't be nearly as detailed in this thread as 8178's outstanding Blue Angel build (I'm too lazy) but hope you'll enjoy it anyway.
Jeff L
< Message edited by Bootalini -- 12/5/2006 6:12:57 PM >
Posts: 146
Joined: 9/5/2006 From: Ottawa,
ON, CANADA Status: offline
Dave, right now, it's a toss-up between the Hyperion 4045-10 and a Neu "ork" 19XX series. Chronos 333 has a post on the RC Groups newsgroup (Gas-Electric Conversion) where he has also converted an Aurora 60 using the Hyperion. His #s are:
Hyp 4045-10 TMM 5024 ESC 8s Lipo (3700mAh) APC 14 X 12E (55Amps) APC 14 X 14 (57A)
He likened the performance to fitting a YS 120 to the front minus the weight penalty...lots of power! He seems pleased although the big issue with the setup is poor ground clearance on grass. Those older trike equiped pattern ships were meant for 11 or 12" props.
I'm very pleased with my fuselage thus far. She's perfectly straight with everything nice and square. Ref weight, I'm at 360 grams (.75 lb) as seen in the attached photo. I was hoping for lighter but at least it's very stiff in the wing attachment area. I'll try to shave grams when I carve and hollow the top and bottom blocks.
Jeff, Thanks fore the speedy reply. I'll check that thread out. Looking for a "pattern" project this winter for electric. I have the Compensator planset from AMA. Also Kaos and Super Kaos. I'm a pattern flier from the late 70's early 80's in Ohio.
Your build looks good! Keep her straight and light!
Posts: 3031
Joined: 5/25/2004 From: _ , USA Status: offline
Hi Jeff,
I’m really looking forward to following your Aurora build! Thanks for taking the time to share with us. Your work looks excellent and the construction of the parts looks a lot like the technique MK used in the Blue Angel kit!
This classic pattern forum is getting to be pretty darn awesome.
Posts: 14
Joined: 11/20/2004 From: Eustis,
FL, USA Status: offline
Congratulations! The Aurora was my favorite plane of all time. "Back in the day", I built the MK kit which was clearly the best kit I have ever seen. I had a lot of fun with it and I'm sure you will too. Consider the BPA...excellent candidate.
I still have the MK nosegear I used in that plane in 1989. It is the only airplane related thing I saved during my 15 year absence from flying! Funny the things we save...I probably will not use it again so if you are interested in it shoot me an email. I used Supras for the mains and I have recently acquired a set of those too.
Let me know and good luck! I look forward to following your progress.
Posts: 146
Joined: 9/5/2006 From: Ottawa,
ON, CANADA Status: offline
Latest progress as I just finished roughing-out the front-top and rear-bottom blocks which will be "tacked" to the fuselage prior to carving the general fuse shape. Sure wish I had a band saw available.....cutting thick blocks accurately can be tough when all you have available is a small motorized scroll saw! It took a while but the blocks have the proper shape according to the plans. I've included a photo with the bottom cowl in place to depict the rough outline of the bottom of the fuse.
It should be noted that in some areas, I've simplified the construction just a bit. After studying the plans carefully prior to starting the project I came to the conclusion that some areas of the construction were overly elaborate and thus difficult to replicate. Don't get me wrong though, MK kits are first class. And despite the internal mods, my intention is to maintain fidelity with respect to lines and shape.
Next step is to produce the fuse shape templates and start carving/hollowing.
Posts: 146
Joined: 9/5/2006 From: Ottawa,
ON, CANADA Status: offline
I just finished fabricating and gluing both top side pieces of the fuselage. I used 1/2" thick light balsa (approx 6 lb density) for those 2 pieces as I knew they would be difficult to trim given the required angles and curves and the fact that I would not be able to hollow these from the inside afterward. They turned out as good as can be expected with only a few minor gaps in a few spots. The next step is to trim the tops of those shoulder pieces flush with the tops of the fuse bulkheads and then add the top "cap". The top of the Aurora fuse has a constant curve/slope all the way to the vertical stab which is necessitating my having to take my time and be careful.
I also cut the fuse outline templates from some spare 1/8" acid free picture frame backing board that I had lying around. That stuff has a special foam core that is perfect for the job. It's fairly stiff yet easy to cut and sand to shape.
Well, that's it's for now. I'll soon be making a mess of my work area from balsa shavings and dust!
Posts: 146
Joined: 9/5/2006 From: Ottawa,
ON, CANADA Status: offline
After shaping the proper outlines of the top and bottom fuse blocks, I then tacked them in place using only a few drops of thick CA each. After I'm done carving and rough-finishing the outer fuselage, I'll then pop those blocks off and hollow them from the inside. It's a laborious but rewarding process as the fuselage slowly takes it's familiar shape while maintaining a reasonable weight. The one photo shows the 5mm thin ply strips embedded in both fuse sides which are nescessary for mounting and holding the lower cowling in place. Even though I'll be using electric power for this project, I installed a flexi Nyrod throttle cable in case a glow motor should one day make it's way into the nose. That's all for now.
Posts: 146
Joined: 9/5/2006 From: Ottawa,
ON, CANADA Status: offline
Roary, interesting comment which begs opening another can of worms. At the risk of doing that.........my thoughts on the subject: -1600Watts (to the motor) is what I'm planning. Given an estimated 8 lb aircraft weight and resultant 200w/lb ratio, that should be the equivalent to an absolutely fire breathing .60 2 stroke equivalent performance. A fair statement is that all pattern ships, old or new design, simply fly better with an overage of power. My goal here is to build one of the faster pattern airplanes capable of still flying the early FAI style turnarould well....and have excess power which should help. It's a cool design as well. -I've may have already offended some Aurora "purists" out there by virtue of modifying a few things (plug-in wings and stab, slightly thinner airfoil, etc). At the end of the day, it will still look and smell like an Aurora. Might even fly better? Who knows. -Having read about the Senior Pattern Association which I think is pretty darn cool, I noticed that they allow 4-strokes on the old designs. I don't know about you but I attended many pattern contests in the 70s and I don't remember 4 strokes being on the front of those older designs. There may have been the odd one but the 4 bangers of the era were relatively anemic and heavy compared to 2 strokes. I think the SPA is correct to allow certain changes.....it's about keeping the balance between retro/current times/ parts availability, etc. And that's my point: in my opinion, electrics will only gain popularity in the future and the type of conversion I'm performing may become common.
Having said all that, I'm eyeballing a Kyosho Oxalis 50 ARF (for electric power) as
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Aurora 60 Build Thread - Electric Power - 
