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Old Feb 22, 2013, 10:17 AM
Videopilot
Derek_S's Avatar
United States, NC, Charlotte
Joined May 2009
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Yeah, i have had this same problem on several models, including the Skywalker and a RQ-11 Raven. I have never been 100% happy tuning it out, but the Penguin is a real pleasure to fly in a glide so far, so I aim to play with it until I am moderately happy. With any luck this weekend the weather will be nice and I can really get to the bottom of it all.
...
I am a very visual person, but always have problems contemplating thrust on a pusher. But in my mind, the motor is pushing the nose of the aircraft down, if you imagine the wings are a fulcrum in which the fuse can freely spin.

I understand your point about the wash on the stab, but dunno much more to do other than test it out and see I guess?
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Old Feb 22, 2013, 10:37 AM
Launch the drones ...
Ashtabula, OH USA
Joined May 1999
3,040 Posts
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Originally Posted by Derek_S View Post
Is anyone else using a substantial amount of down-thrust on their P? I put 3mm washers on the top of the motor mount. From the side, this amount of adjustment seemed to put the motor pretty close to parallel to the chord line. However, I found I still needed substantial nose-down trim for powered flight (glide was relatively ok). I have now added 2 more 3mm washers to the top, so around 6mm of space. The motor now clearly shows some down thrust when viewed from the side. I have not flown it this way yet. Just wondering if this is someone else's experience as well?
I use just the 3mm washers. All planes will increase lift with an increase in speed - you have to decide where you want your plane to fly level - while gliding, or under full power, or something in between. I always set mine up for gliding level - and just apply some down during full power, or not. You can also setup mixing, such that with application of throttle, some down elevator is dialed in.
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Old Feb 22, 2013, 10:47 AM
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Joined Jun 2012
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I wonder if the developer of the airframe has the where's and why's of placement, or if they used the empirical approach with a dose of 'been there, done that'.

Tre
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Old Feb 22, 2013, 10:48 AM
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USA, NH, Alstead
Joined Oct 2007
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I use just the 3mm washers. All planes will increase lift with an increase in speed - you have to decide where you want your plane to fly level - while gliding, or under full power, or something in between. I always set mine up for gliding level - and just apply some down during full power, or not. You can also setup mixing, such that with application of throttle, some down elevator is dialed in
Yes, normally the throttle is considered the "climb" control input and the elevator is considered the "speed" control input so to climb you would expect to increase throttle and to increase speed you would then apply down elevator " trim". In a model this trim control could be on knob or switch or mix that would add down elevator to trim to level cruise at a given cruise throttle setting.
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Old Feb 22, 2013, 11:18 AM
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Derek_S's Avatar
United States, NC, Charlotte
Joined May 2009
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Quote:
Originally Posted by Tim Green View Post
I use just the 3mm washers. All planes will increase lift with an increase in speed - you have to decide where you want your plane to fly level - while gliding, or under full power, or something in between. I always set mine up for gliding level - and just apply some down during full power, or not. You can also setup mixing, such that with application of throttle, some down elevator is dialed in.
That is a good point, and something I haven't considered. (But I will consider as I get her better tuned), but I can say with certainty I am not withing the allowable range of that function. I.e. I have FULL down trim right now, and at high power still need a little down elevator. Perhaps I still have some tweaking to do on CG too (at about 80mm now) as she still 'feels' nose heavy to me, and likes to "porpoise" a little.
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Old Feb 22, 2013, 11:20 AM
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Derek_S's Avatar
United States, NC, Charlotte
Joined May 2009
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Originally Posted by u2builder View Post
Yes, normally the throttle is considered the "climb" control input and the elevator is considered the "speed" control input so to climb you would expect to increase throttle and to increase speed you would then apply down elevator " trim". In a model this trim control could be on knob or switch or mix that would add down elevator to trim to level cruise at a given cruise throttle setting.
Good idea. Or, I would for myself plan to use an active mix that increases elevator trim given a certain throttle %. I did this on my Estar and worked great once you get it right. My problem with a preset is I don't fly long distance really, so I usually am constantly changing my speed, altitude, and vector.

Anyone also using flaperons/spoilerons? I programmed them in on a slider, but haven't really had a good chance to try them. Gotta get normal flight locked in first. I was really afraid I would have trouble landing her in tight spaces, but with the FPV gear and under the hood, it isnt too bad as I can dip in and flare pretty hard for what I would consider 'perfect' landings (in my book).
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Old Feb 22, 2013, 03:26 PM
Go Fly Yourself...!!
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United States, WA, Bonney Lake
Joined Oct 2004
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Hey Kids...

Here's RC Models Reviews, Finwing Penguin Review Part 2:
Review: FinWing Penguin FPV (part 2) (8 min 27 sec)


Enjoy..
D-Man
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Old Feb 22, 2013, 05:22 PM
KK4NOP
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United States, VA, Virginia Beach
Joined Aug 2005
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Originally Posted by DFloth View Post
Hey Kids...

Here's RC Models Reviews, Finwing Penguin Review Part 2:
https://www.youtube.com/watch?v=M_tkj25_uIs

Enjoy..
D-Man
I really like his reviews. Honest and straight forward.
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Old Feb 22, 2013, 07:51 PM
Seattle, WA - USA
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Me too
"Brilliant!"
"Absolutely over the moon!"
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Old Feb 22, 2013, 08:55 PM
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USA, NH, Alstead
Joined Oct 2007
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He should try the original canopy. It is much more streamlined and weighs 4 oz!!!! less. I put mine on today. My FPV camera is "looking through it" but if it winds up looking as bad as the video I could do like Markq did and cut a hole in it. I am a couple of months out from flying it so I'll leave it for now.
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Old Feb 22, 2013, 09:14 PM
'FPV'er...not a "LOS'er
Vantasstic's Avatar
Las Vegas, NV
Joined Sep 2003
18,474 Posts
Quote:
Originally Posted by Derek_S View Post
Is anyone else using a substantial amount of down-thrust on their P? I put 3mm washers on the top of the motor mount. From the side, this amount of adjustment seemed to put the motor pretty close to parallel to the chord line. However, I found I still needed substantial nose-down trim for powered flight (glide was relatively ok). I have now added 2 more 3mm washers to the top, so around 6mm of space. The motor now clearly shows some down thrust when viewed from the side. I have not flown it this way yet. Just wondering if this is someone else's experience as well?
With my experience with pushers, the Penguin has it backwards on the the thrust line thingy. I've yet to build my Penguin, but was planning on putting washers on the BOTTOM of the motor mount not top.

Because the motor is behind the c/g. Tilting the motor down in back 'lifts' the tail, thus the nose tucks down under power. Adding more down tilt should just make the situation worse.

The best scenario is to have the motor's thrust line pass through the planes C/G intersection. Thrust line above the c/g, on a pusher, will cause nose down under power. Passing below the c/g ona pusher will cause nose up under power.

Look at the EZ Star, for example. Which way does the motor point? With the front of the motor lower than the rear of the motor. The Penguin is the exact opposite.

To test you can mount the motor without washers and fly. Then put washers to the bottom motor mounts and fly. Then move the washers to the upper motor mount and fly. Choose the position that felt best to you and fine tune the thrust line until power on and power off cause little/no pitch difference.
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Old Feb 23, 2013, 12:35 AM
Seattle, WA - USA
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Joined Sep 2003
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Originally Posted by Vantasstic View Post
Because the motor is behind the c/g. Tilting the motor down in back 'lifts' the tail, thus the nose tucks down under power. Adding more down tilt should just make the situation worse.
Hey vantastic,

Derek_S currently has to use too much down elevator for level flight under power so you are describing exactly the same thing he has tried, to point the motor down because he wants to bring the tail up. It apparently hasn't worked very well.
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Old Feb 23, 2013, 09:31 AM
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Norway, Sor-Trondelag, Trondheim
Joined Apr 2010
5 Posts
My Penguin

Hi folks.
This is my FPV platform. Ready for the electronics. I have covered the wingtips, nose and leading edges with UltraCoat.

LRS: Orange RX
Video Transmitter: FatShark 5.8GHz 250mW
Video on ground: FatShark SD
OSD and Autopilot: RVOSD (RangeVideo OSD)
FPV Camera: Sony 600TVL Super HAD CCD II
Recording Camera: GoPro Hero 3 Black Edition

Future Equipment:
Lawmate 1.3GHz 1000mW (or more) video transmitter.
DragonLink or Thomas Sherrer LRS.

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Last edited by BadBoyBubby; Feb 23, 2013 at 09:59 AM.
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Old Feb 23, 2013, 11:27 AM
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London-UK
Joined Sep 2007
244 Posts
PG ALLYPALLY 23 02 2013 (2 min 16 sec)
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Old Feb 23, 2013, 11:51 AM
McCleary.11's Avatar
United States, OH, Delaware
Joined Mar 2006
757 Posts
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Originally Posted by BadBoyBubby View Post
Hi folks.

Future Equipment:
Lawmate 1.3GHz 1000mW (or more) video transmitter.
DragonLink or Thomas Sherrer LRS.

Love the color scheme! Very simple. What made you decide on the Lawmate 1000mw?
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