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Old May 01, 2006, 09:34 PM
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How much elevator throw is enough for a Siren?

I'm real happy with the control deflections I'm getting with the ailerons, but the elevator seems to be minimal to me. the manual gives suggested high rate throws as being 1/2" each direction, and low rate at 5/16" either way. My max throw is like 1/4" each way. I see no way to improve things mechanically, and the servo (HS-55) appears to be maxed out. Suggestions? Or am I good the way things are?
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Old May 01, 2006, 09:59 PM
KK6MQJ
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I had the same problem, as there is not really very much room inside the tail to put a larger horn on the servo. Look here and read the last two posts in the thread, mine and Andy's reply.

And I have about a half dozen flights on mine so far with no need for more elevator! What power plant you going with?

Good Luck!
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Old May 02, 2006, 12:41 AM
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Move teh CG back? Or move the elevator horn forward close to the hinge line. The instruction showed a 1/2" space between the higne line and the base of the horn, move it forward about 1/8 of a inch. See how much more throw can you get. Option 2,you can move the attached point to the skin of the elevator, the pushrod will push from a smaller angle. You will need to extend the pushrod for this option.

I don't have a Siren, but I see all this from the online instruction.

Brian, an EAJ
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Old May 02, 2006, 02:28 PM
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I have the same exact motor as you, except I opted for an Electrifly 10 cell NiMh pack, thinking the extra mass would be helpful in speed retention, and the power won't suck either. Andy W. is the wellspring from which I've drawn much of my inspiration for this bird....although I bet he can't believe mine STILL hasn't flown! But it was finished on Sunday, and is ready for glide tests. Spoilerons look like they'll really do the trick as far as getting it slowed down to land, and it's only a matter of time before I put my assembly skills to the acid test! BTW, I had to add 3/4 oz. to the tail to balance mine at around 2.75" back (or maybe a bit more...have to double check....but definitely in the range suggested by previous threads on the subject. Can't wait to get this puppy in the air! It looks downright BEAUTIFUL if I do say so myself!

Thanks for the feedback, and good luck with yours!

Quote:
Originally Posted by BARNESJONR
I had the same problem, as there is not really very much room inside the tail to put a larger horn on the servo. Look here and read the last two posts in the thread, mine and Andy's reply.

And I have about a half dozen flights on mine so far with no need for more elevator! What power plant you going with?

Good Luck!
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Old May 02, 2006, 02:30 PM
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Interesting idea....I was wondering why they had the horn so far back, but figured they knew what they were talking about! I may try that.

Quote:
Originally Posted by bhchan
Move teh CG back? Or move the elevator horn forward close to the hinge line. The instruction showed a 1/2" space between the higne line and the base of the horn, move it forward about 1/8 of a inch. See how much more throw can you get. Option 2,you can move the attached point to the skin of the elevator, the pushrod will push from a smaller angle. You will need to extend the pushrod for this option.

I don't have a Siren, but I see all this from the online instruction.

Brian, an EAJ
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Old May 02, 2006, 03:03 PM
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and the power won't suck either

I am flying mine on TP 2100 Pl's and I normally do not exceed half throttle, as it goes up like a rocket. My CG is around 70mm, per recommendations of this and other threads. AUW is approx. 36 ounces if memory serves me correct
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Old May 06, 2006, 05:06 PM
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Well, going on intuition (and being hesitant to reposition the elevator control horn further forward, leaving two unsightly holes , and doing lord knows what to its structural integrity, I maidened the Siren today at last. And it was a HOOT! OK....not really a Hoot...that would have been a REAL hotliner. But it was quite fun, and flew like a dream. Thanks to Andy W., Soholingo and all the others who, wittingly or unwittingly, helped make this project such a success!

The CG was back around 2.8", and there's just enough room between the battery and Rx to move it back a little more if necessary. Elevator travel proved to be a non-issue, despite being significantly less than the suggested low rate throws in the manual. It's not as pitch sensitive as it could be, but there's plenty there to do averything I need it to do (like miss the ground on those vertical dives), and it retains sufficient pitch authority all the way to landing.

Speaking of landing, it likes to catch a wingtip, no matter how level I try to keep it during the slide. So far, no damage to the saddle area as others have seen, but time will tell. I have spoilerons programmed, but the winds today made them unnecessary.

As for power, I used the AXI 2826/10 recommended by so many, and I'm not disappointed. Tried 12x9.5 and 14x9.5 folders, and it seemed to scoot pretty well. Not as much vertical as I would have thought either way, but I'm being a little conservative with throttle usage in the interest of keeping current levels managable. Using a 2000 mah, 10 cell Electrifly NiMh that stuffs in very neatly. Energy retention, as has been mentioned many times, is minimal, so as a hotliner, it's rather tepid. But as a change of pace from my nitro stuff, it's just the ticket. Does make me hungry for more though....trying to picture an Ion in my future.....

Final note: One club member commented that it was "a weird plane...just like you"....which I took as a compliment.
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Old May 06, 2006, 05:39 PM
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Glad you enjoyed the Siren, itís a great lazy type plane that you can toss around, thermal, have fun with and will serve you well. When you get bored of the Siren donít bother with the Hoot, get a Zoom and put a Neu 1509/1Y/5.2 in with 10 cells and when you get bored with that put in 16 cells. You will have a tiger by the tail then.
GL and have fun, Steve.
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Old May 06, 2006, 06:06 PM
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hey IFlySlow .... I am flying my new Siren on the same Axi as you and the vertical with a 13x7 and a Thunder Power 3 cell 2100 Pro-Lite lipo is crazy! I use a lot of throttle management, probably not exceeding a smidgen past half-throttle?! I have a 14x9.5 but haven't felt the need to even try it - yet! My next bird will be on the way soon, a Bandit, courtesy of Soholingo.
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Old May 06, 2006, 06:49 PM
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I fly it with a Hacker B50/9S 10GP2200 15/15 prop about 750 watts. I would not call it a rocket ship but it gets to 800 feet fast. Whatís nice is when you cut the power it climbs for an other 200 feet. Light enough to thermal, lots of fun.
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Old May 07, 2006, 06:17 PM
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BARNESJONR:

Where did your CG end up with the LiPo's? I imagine it's considerably lighter than mine, so it probably is better for thermal flying (although I was quite pleased at how well mine thermaled today, even with all that weight!).

Also, with your setup, is it possible to fit a 3S2P pack in there? I need to read the other threads for that oneI guess.

Anyway, today was a great day to be an R/C pilot. Weather was perfect, and I had a cool new plane that everyone was checking out (since I usually only bring my Tiger 2, it was nice to be the guy with "something different" for once!

Quote:
Originally Posted by BARNESJONR
hey IFlySlow .... I am flying my new Siren on the same Axi as you and the vertical with a 13x7 and a Thunder Power 3 cell 2100 Pro-Lite lipo is crazy! I use a lot of throttle management, probably not exceeding a smidgen past half-throttle?! I have a 14x9.5 but haven't felt the need to even try it - yet! My next bird will be on the way soon, a Bandit, courtesy of Soholingo.
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Old May 07, 2006, 07:07 PM
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Everybody that has flown this plane before me said the CG needed to go back quite a bit from recommended - I think I went for 70mm? I added one 1/4 ounce weight on the bottom of the nose but on a landing it came off and I flew without it and it was fine. I am not 100% sure what it is at this moment but will try and check next time I take it out.

I am only flying with a single Tp PL 2100 3S in mine. I think two would fit though. Another pilot here on RCGoups was doing it and I think he mentioned to me in a PM that he puts them end to end ... IE, one slides in and forward and then the other lays directly behind the first? My AUW is 2 pounds 4 ounces and it goes vertical like a homesick angel! Though this is my first plane of this type, all of my other electrics are usually set-up for at least 100 watts per pound, so I am used to planes that you can stand on their tail and watch 'em go vertical forever .... but this siren brings a grin to my face!! Two of my buddies have launched it for me and both of them were blown away by the pull when I ran the motor up while they were holding it!

I want to put my radar gun on my siren, as soon as I get better at taking her up HIGH and then doing the screaming dive. I am ok at it now but get a little nervous when it is so high that i feel like if I blink at the wrong time I will instantly be confused as to orientation. But I now there are guys who are going way higher than I do, routinely! I had my wifes family in town this weekend, so no flying. I'm already looking forward to next weekend, even though it isn't even monday yet.

Yeah I hear you on the "great day to be an RC Pilot" thing ... I know that feeling, since for some reason I seem to be driven by trying new variants and am usually the one in my circle to go in a new direction, like the Siren. And I love it when it is a bright blue day and you have a bunch of the "kids" from the hangar crammed in the back of the wagon and you are looking at a whole day of flying!!!! It's the best!
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Last edited by Bajora; May 07, 2006 at 07:08 PM. Reason: correct typos
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Old May 08, 2006, 08:16 AM
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Very cool! I know the weight savings alone would result in better vertical than I get now. As I said, I'm using the Electrifly 10 cell 4/5SC batteries, and they're pretty heavy (and as a reult, my vertical is more like a slant!). So far, in the interest of longer flights, I've only done steep climbs once in awhile, and done more partial throttle climbs for real altitude. One fun thing I do is to run straight & level at pattern altitude when other glow planes are flying, and I overtake like they're standing still! And 'cuz it's so quiet, they never know I'm coming until I blow past them! I've also had fun running around 1/3 throttle inverted at a few feet over the runway. I like doing that with ANY plane, but when this one come whispering in, and the guys see how low I am, I can hear them suck in their breath and hold it until I'm climbing again. I'd do that without power, but the energy retention on this bird is low enough to make it an iffy proposition at best. Hey...it's all good!

Quote:
Originally Posted by BARNESJONR
Everybody that has flown this plane before me said the CG needed to go back quite a bit from recommended - I think I went for 70mm? I added one 1/4 ounce weight on the bottom of the nose but on a landing it came off and I flew without it and it was fine. I am not 100% sure what it is at this moment but will try and check next time I take it out.

I am only flying with a single Tp PL 2100 3S in mine. I think two would fit though. Another pilot here on RCGoups was doing it and I think he mentioned to me in a PM that he puts them end to end ... IE, one slides in and forward and then the other lays directly behind the first? My AUW is 2 pounds 4 ounces and it goes vertical like a homesick angel! Though this is my first plane of this type, all of my other electrics are usually set-up for at least 100 watts per pound, so I am used to planes that you can stand on their tail and watch 'em go vertical forever .... but this siren brings a grin to my face!! Two of my buddies have launched it for me and both of them were blown away by the pull when I ran the motor up while they were holding it!

I want to put my radar gun on my siren, as soon as I get better at taking her up HIGH and then doing the screaming dive. I am ok at it now but get a little nervous when it is so high that i feel like if I blink at the wrong time I will instantly be confused as to orientation. But I now there are guys who are going way higher than I do, routinely! I had my wifes family in town this weekend, so no flying. I'm already looking forward to next weekend, even though it isn't even monday yet.

Yeah I hear you on the "great day to be an RC Pilot" thing ... I know that feeling, since for some reason I seem to be driven by trying new variants and am usually the one in my circle to go in a new direction, like the Siren. And I love it when it is a bright blue day and you have a bunch of the "kids" from the hangar crammed in the back of the wagon and you are looking at a whole day of flying!!!! It's the best!
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Old May 09, 2006, 02:02 AM
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Sacramento, CA
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Hi guys. I recently picked up a Siren and noticed that the covering has many wrinkles and elongated bubbles in it. I've smoothed most of them out with my iron and heat gun, but there are still quite a few I can't get out. Is this common on your planes as well? Thanks.
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Old May 09, 2006, 06:25 AM
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Yeah, when I opened my box, I was a little upset and it took me quite a while to get it looking like a new arf should.
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