Posted by jokeane |
Aug 31, 2008 @ 10:01 AM | 2,801 Views
Dave and I returned to the flying field yesterday, and brought the T-34 out for its second maiden attempt.
The weather was great, but a tad more wind that the previous night. In theory, for the larger planes like the T-34 and the Sky Cat this isn't a huge problem.
To start with we setup my Sky Cat and the buddy box and double checked all the trims. For the first flight I handled take off and landing, but Dave flew the rest of the flight un-aided. The Sky Cat is pretty responsive, but Dave did a good job and got a feel for what happens when you get a gust of wind strong enough to knock the plane around a bit.
Next up was the T-34. I took it up for a short flight and trimmed it out for neutral flight. As per the official blog, it actually just needed some down elevator to compensate for the full down fixed flaps (part of the 'training' setup). The plane flew very nicely and has very good coloration for orientation. As many people have told me, the larger the plane the 'smoother' it feels in the sky. I'd say this is definitely true with the T-34. My landing was decent, but not perfection.
We hooked up the buddy cord on the two Spektrum 6xi radios, and once again made sure the trims were properly entered into both radios so they were setup identically. For this flight I was on the Master and Dave on the Slave radio. I gave Dave control, and he taxed out and took off like a pro!
He flew a bunch of nice circuits, and looked to have nice control of the aircraft. He...Continue Reading
Posted by jokeane |
Aug 30, 2008 @ 03:34 PM | 2,470 Views
As I've mentioned previously my friend Dave has a new T-34. Well we attempted to fly it last night using a trainer / buddy setup. The T-34 is a large balsa ARF - 55" wingspan. Around the size of a ".40" gasser, but the electric power system is supposed to be .25 equivalent. We tested it static, and it pulled a bit over 40 amps on the bench, and almost 500 watts of power at full throttle.
I was on 'Master' and Dave was on the 'Slave' controller. I gave him control so he could taxi and take off, the idea being he needed to learn how and gee whiz, as long as you are gentle on the sticks and give the plane some time to build up speed, take offs are normally not a big deal.
Not this take off... Dave throttled the T-34 up and right after it left the ground it pitched back almost completely vertical! There was a lot of exclamations of "oh sh*t" all around. I took over and punched the throttle to full and gave it full nose down. I got it back under control and throttled back to 40% to 50% throttle ... the plane wanted to climb like crazy. It was all I could do to keep pushing the nose down trying to keep it level. I did a few circuits like this and then I started trying to shoot landings and bring it down. It did NOT want to come down. Even though killing the throttle completely would slow it some, I had to really push the nose down to get it to decrease altitude. Needless to say the landing was very scary, but I did finally get it down all in one piece. I don't believe there was any damage that I saw. Not my smoothest landing.
Afterwords I was shaking from the adrenaline rush. It was by far the most hair-raising flight I've had in quite a while. This is a *beautiful* balsa plane which I would have hated to damage.
From what we can tell, the CG was aft of what it should have been and/or the idea of having full down flaps (see E-Flite T-34 thread) isn't such a great one.
Posted by jokeane |
Aug 30, 2008 @ 01:46 PM | 2,285 Views
I finally got around to building one of two Brio 10 ARFs I've had on the shelf for about a year. Here are my impressions on the build, my setup and my first flight.
The build was very straight forward. The ARF kit was very complete hardware-wise and the manual was well written and illustrated with nice black and white photos showing most steps. I had to do a bit of warp removal with the stab, tail, rudder and elevator. Wings looked pretty warp free. I added larger wheels and left off the wheel pants since I fly off grass. I also replaced the stock spinner with a nicer 3rd party black 1 3/4" spinner. I'd say it took maybe 12 hours to build give or take. Pretty fast. Nothing tricky at all (unlike the Sopwith Camel I just built).
I went with a TowerPro 2908-10 brushless motor and TowerPro 30A ESC that I had pulled from my scrapped GWS Formosa II. APC 11.5x5.5 prop. FlightPower EVO25 1800 mAh 25C 3S lipo. Two HS-55's on the ailerons, two bluebird servos which as a tad stronger than the HS-55's installed in the rear locations for rudder and elevator. Total weight 33 oz.
I may prop up to a 12x6 in future.
I had no problems setting the CG to a bit behind the forward-most CG location from the manual. With the nice battery location setup, it appears that it won't be hard to tweak the CG back a tad when I'm fully comfortable flying the Brio and want to try more tricky stuff.
A beautiful WI late summer evening at the Badger Prairie field....Continue Reading
Posted by jokeane |
Aug 30, 2008 @ 12:49 PM | 2,436 Views
My friend Dave is getting into R/C and has picked up a sweet RTF trainer package (E-Flite T-34). It comes with the same 2.4Ghz radio I've been using so we figured we would test out the trainer / buddy system with my Sky Cat.
Long story short, this wasn't quite as straight forward as you would think. Apparently the way things work you have to have each radio programmed EXACTLY the same, right down to the trims.
Needless to say, I missed the trims when programming Dave's radio to match mine. Dave was attempting to fly my now completely un-trimmed Sky Cat. Since he was new to R/C, he didn't realize he needed to trim it out (nor did I) so he experienced some very frustrating attempts at flight. The good news is the switch between master / slave worked flawlessly, so I was able to save things on each loss of control. This was good practice for me. :-)
Dave blamed himself, but upon further review it was clearly a setup problem with not getting his radio tweaked to match mine. We will continue to work on this, and I think now that we understand the problem it will work better in the future.
The Sky Cat has now transitioned to a solid sport aerobat in its current setup. Nice and predicable flights, some simple aerobatics. Decent power, but not overpowered. I might be able to prop it up a bit from the 11x7. Handles winds decently and landings are nice and predicable.
Posted by jokeane |
Jul 21, 2008 @ 10:02 AM | 2,504 Views
So I did a pretty significant re-work of the Sky-Cat after getting it home from the maiden flight. Found out that the glue I used for some of the assembly just wasn't working well at all. (Ultimate R/C Foam glue - go figure. Seems to work well on blucore and depron, but not Elapor.)
So I tore much of the plane apart, cleaned off the offending glue, repainted some spots and re-assembled it. For the re-assembly I used medium viscosity CA and kicker. This worked VERY well. All the Elapor joints feel much more solid. Also added a magnet for the battery hatch. I re-hinged the ailerons, I'm much happier with this hinging job than the last.
I dropped the prop down to an APC 11x8 - just to try it out for the next flight.
So it is all set for next flight. Weather seems crap today, but we shall see.
I got up early today and went to the Badger Prairie field in an attempt to beat the weather (which looks iffy at best today). Badger Prairie aeromodel field is a Dane county park with large grass area for take-off and landing surrounded by a mostly tree-free prairie.
I had three totally new items with me to try out, new Spektrum 6xi radio and two new planes which I had not flown previously.
Winds were 0-5 MPH. Pretty calm, but not totally.
I flew the Green Models / Powerline Sopwith Camel first. I was pleasantly surprised to find it seemed to have plenty of get up and go, even with the tiny little stock brushless motor. When I tested it out static it only pulled 10 Amps, so with a 3C lipo that is only 110 watts input power.
After a bit of trim it flew pretty well, although it may need a bit more weight in the nose. It seemed a tad pitch sensitive, which usually indicates the CG may be a bit aft of where it should be. With my 1700 mAH 3C lipo, it had plenty of juice. I didn't time it, but I flew two roughly 5 minute flights and it didn't seem even close to out of juice.
Flying was very scale-like. Not too slow but not all that fast. The Sopwith would loop happily. Landing was interesting, since with the draggy airframe you needed a fair amount of throttle to keep the plane moving as you bring it in. I did several landings and the large wheels worked quite well on the grass. Ground taxing was pretty good, although I did nose it over once when I taxed a bit fast...Continue Reading
Posted by jokeane |
Jul 06, 2008 @ 11:30 AM | 3,030 Views
Just finished assembling a Green Models / Powerline Sopwith Camel ARF that I picked up from Hobby Horse.
This balsa ARF comes with motor, ESC and servos for ~$170. Which seemed like a decent price.
For an ARF, it is a pretty advanced assembly. Lots of fiddling around with flying wires and pull-pull controls. Also my kit required a lot of re-shrinking of the covering, and even with a lot of work not every wrinkle was eliminated.
The motor that comes with it seems somewhat under-powered when testing it statically. It comes with a 10x5 prop, and draws 10 amps max with a fully charged 1700 mAH 3S lipo.
Well I've build and flown my Formosa II. I'm an intermediate flyer / builder. I've been doing R/C planes for about three years.
I've built and flown many other GWS planes; ME-109 (x2), BN-2 Islander, Spitfire. Several of my friends have the Formosa I, and I've seen it flown. I've also built and flown a number of Multiplex foamie kits; TwinJet, MicroJet, Sonic Liner and the Magister.
Formosa II w/ brush-on acrylic paint over about 1/3 of the surface.
4 HS-81 servos
Hitec 6 channel reciever
Balsa Products BP30 (Tower Pro 30) amp ESC
Gorrilla Bob's XM2908-10 Brushless motor (similar to Balsa Products motor)
2100 mAH 3S lipo battery
10x5E APC prop
Handmade motor mount from basswood + included stick.
CG located right on the spar.
All up weight was almost exactly 32 oz (2lbs)
* Good looking design
* Easy to build
* Transparent canopy
* Flys well (pretty easy to fly)
* Takes off from grass easily (ROG)
* Very poor manual! (No CG location, no wiring info, no control surface throws, .etc)
* Flimsy cowl plastic (needs to be stiffer)
* Landing gear is a joke. Needs thicker wire / redesign.
* Battery bay isn't large enough to fit most 3S lipo packs, and no way to fix it without dumping stock hatch or chopping into wing. I just left hatch off entirely which isn't very clean aerodynamically.
I flew three total flights, each about 5 min. long. The motor is definitely powerful enough to haul this bird...Continue Reading