What ya changing for 09

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Lee Liddle
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Post by Lee Liddle »

Good shots from Sunday (and Friday night) Ed.

Ed`s Open B P-39s flew awesome. They climbed out perfectly from launch, then just a few clicks of trim here and there had them dialed in. They are just as maneuverable as any Open design that I`ve ever seen, and look good in the air. As a conventional airframe, it`s easy or keep track of their orientation and just have a very solid "feel" to them.

As Ed said above, the stab and elevator need just a little more bracing (easy) to handle the Open B loads. Other than that, they were ready for LSN after 30 seconds of trim flight. Isn`t that what that 90 second window is for?
Lee Liddle
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Post by Lee Liddle »

On the SSC P-51. I built one of these years ago as my last IC powered SSC warbird. It flew well, but I don`t think I ever flew it in an official heat.

I`ve been playing with Scorpion outrunners for SSC power to try to lighten the power system some.. Nothing really new, because Slam and Drewjet were using these several years ago with success, but I thought that they might be a good match for the SSC warbirds coming out of Texas Fulgerwerks.

Even with a patched up wing, the weight of the Mustang is about 45oz. That would be no more than 43 with a new wing.

On 6s the motor only pulls about 16 amps, so a pair of 3s 1800mah batts in series is all that you need to get plenty of power for 5 min. A pair of 3s 2000mah would even be better at a slight weight penalty of course, but then you could just use a pair of good 3696 batteries to power an SSC.

At about $50 shipped, the motor is more expensive than the average 3696 motor, but with a 1080kv and a 3.50z weight, it is also a perfect fit for 3696. So you can fly both events with the same equipment.

The final piece to the puzzle is the Turnigy 40 amp ESC with a switching bec circuit. The esc is good up to 6s and can be used to power the rx/servos even with 22.2 volts of input power. This saves at least 1.5oz of battery weight.

AUW of the power system is about 17oz, so that leaves about 25oz for the airframe if you want to stay at min weight for SSC.

I`ll put this info in the E-SSC section as soon as I get some more time on the system. I want to make sure that everything is all good before recommending that someone run out and buy this stuff. But so far, so good.
Lee Liddle
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Post by Lee Liddle »

One more thing. The motor that you see on the Mustang is not the Scorpion. It is a Turnigy SK series motor. It has similar specs to the Scorpions, but is 1/2 the price.

I flew the motor stock for several flights and it performed the SSC duties without a problem, but the windings are done with very thin gauge wire, which is very fragile. I`ve since rewound the motor (another thread entirely) and have it producing the same numbers as the Scorpion. A $26, 3.5oz E-SSC motor that runs great on $35 worth of batteries.....Very interesting. More on this later too.
AIM
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Location: Montpelier, Ohio

Post by AIM »

I'm still playin with the flat bat although not at any fast pace. I've tried three different motor mounts and three different tails and believe I've finally came up with the combo that I don't mind building. Prior to any test flights I'm trying to arrive at a user friendly build. If they are a PITA to build I'll hate em no matter how good they fly.
My motor mount as of now is 2 pieces of 1/4" thick 1 1/2" angle alum about 3/8" wide screwed to a ply firewall. My tail ends up a full flying stab (although I called Jones the other night braggin about a diff tail design[8D]).
For now I'm gonna mount a B2 wing with shims on it but I wanna try a Roid wing that I have, mounted at zero incedence next (I can't remember what airfoil they are but they are pretty flat bottomed). I hope the zero incedence thing works out to avoid shims on the next planes but we'll see.
Looks like weight wise they will be pushing it but the design so far is clean so maybe they will work out pretty good for LimB.
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lightning
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Location: USA

Post by lightning »

Hey AAAAAAAAAAron, I don't care how you build 'em, just as long as I know they are orange so I know which plane to shoot for without having to look too hard[}:)][}:)][}:)]
AIM
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Location: Montpelier, Ohio

Post by AIM »

Yep they'll be orange...
Captain America
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Post by Captain America »

Contractor cammo...
M. Gillette
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Post by M. Gillette »

Full flying stab eh?? Sounds cool, have you flown it yet?? How is the roll rate??

Roll rate -- Thats somthing I've been trying to improve with my fleet. Watching Brian's flying style his Avengers seem to have a faster roll rate than the Phencepost. I'm wondering if it's the full flying stab that gives the Avenger the ability to roll so well?? It certianly isn't lack of aileron throw on my part.....
sgilkey
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Post by sgilkey »

Eric's Phencepost and Brian's AVENGER B2 wings are the same and as official test pilot and bottle washer, I don't think there's a diff in roll rate between them. We took a few steps several years ago to try to improve roll rate:

1) generous bevel on the aileron bottom LE, followed by radiusing the edge
2) you can also slightly radius the bottom back edge of the core (we use no TE stock)
both 1 and 2 are just to get max throw of the ail before it hits the core
3)over/under tape hinges, make sure there is a SLIGHT space between the core and ail for free movement, but not so much that the hinge line can just shift up and down due to slop
4) most important change: we use hommade control horns cut from phencepost mtl that allow a big footprint on the ail, while still placing the pivot point on the hingeline. We use a long servo arm and a fairly short horn, carefully lay out the servo/p-rod/horn to make sure it's all in a line and not binding (dual servos) to get max throw

sometimes a wing will actually roll faster, or at least as fast, with LESS throw. I usually set them up for max throw possible until the servo stalls, then test fly, and reduce throw with ATV until the roll rate actually starts to slow down. Sometimes, I don't dial in any ATV, sometimes I can, which gives me the same roll rate for less throw (drag).

Even so, I would say the roll rate on our 64 inchers is never quite enough. I don't like a ton of roll rate, but Brian likes as much as he can get and would take more, that's one nice thing about the Rus wings. On 72 inch wings, there is never enough roll rate and they are sluggish in roll. That's why Brian always likes flying the scale classes, he loves the fast roll rate they can get. Eric is not particular and doesn't seem to mind a slower roll rate.
gsjames
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Post by gsjames »

Gettin' ready for the season... I cut 8 sets of cores for SSC and OpenB using my "pivot arm" one-man foam cutter. I also significantly enlarged and swept the vertical tail of my Battle Axe clones since the don't seem to have enough directional stability for my liking.

Looks like we are going to have the chance to fly 3 Open B events this year in North TX, with a contest EVERY MONTH from March through December [:D], so I figure that I'd better have a LOT of extra wings. The new wings have a new airfoil [}:)] and use 1/4" x 3/8" spruce spars (tapered to 1/4" x 3/16") that Aircraft Spruce and Specialty cut for me. They use "Icemaker tubing" as a leading edge reinforcement as per Evan Wenger. I been saving my nickles and dimes and have bought a bunch of HS-82MG's and HS-85MG's as well as 6 Corona synthesized receivers (72Mhz $21.95 ea). Although I have two 2548 P-51 kits from Texas Fluwerks, it's not looking good to have them available for the LSN. Hopefully, I'll have them available later in the season. Ed really likes the scale stuff and although it doesn't really interest me much at all, since he's been "honcho-ing" most of the contests, "When in Rome, (or North Texas) do as the Romans do", so I guess I'd better get 'em built. We also have a very active Q-25 racing schedule here, so I'm trying to decide if I want to divide my time.

My rookie year was so much fun, I can hardly wait for this year's season to start.
AIM
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Location: Montpelier, Ohio

Post by AIM »

Well my flat bat plane dubbed the "flattlefly" is basically done. All up weight is 3lb 5.5oz.
The first one took forever to build but I think basically because I changed things about 2 dozen times. I should be able to knock out the rest in a normal time frame. Hopefully get some decent weather here in the next couple weeks to get a test flight in. I've no doubt it will fly nicely. Once a few test flights are done I'll start building the rest of the fleet. For about the 6th time I changed the tail again. I started with about 3 versions of a conventional tail and then went to a flying stab. After staring at that for a few days I went back to the conventional tail. (I really don't know why)
Either way is easy to build so I want to try a flying stab on the next one. I think I just felt more comfortable with a conventional stab/ele because I've never set up or flown a full flying stab. Once the plane is dialed in I'll be more comfortable trying it.
There are a few things I don't like about the bat but if I can reduce damage to my radio gear I'm willing to get over my dislikes.
CONS:
The bat is expensive- about $8.50 shipped
Motor must be angled so muffler clears (straight up is just easier)
No square surfaces for tail (not terribly hard to deal with though)
Heavier than the post by 2.5 oz

I don't wanna post any PRO's about it until I fly it in combat.
I'll post pics later this week.
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boiler
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Post by boiler »

Pro: Lots more room for stuff inside.
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lightning
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Post by lightning »

Pro: Protects everything, including the fuel tank, because you can get it all inside instead of hanging everything on the outside.
Pro: They're tough as He!! [:D]
M. Gillette
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Post by M. Gillette »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by boiler</i>
<br />Pro: Lots more room for stuff inside.
<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">

Yeah with all the extra room inside you could fill it with Jolly Ranchers and bomb the flight line, distracting other pilots and swoop in for a cut or two. Would that be a Pro??
sgilkey
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Post by sgilkey »

Aaaaaaaaaaaaaaron, check out the SSC thread, Randy Hodges has posted photos of his latest e-flat bat, maybe his tail group will give you some ideas....
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