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Old Dec 05, 2012, 11:09 AM
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Ory: Keep in mind that if you disable the brake, your motor will windmill when you shut it down causing a lot of drag and compromising your glide performance. Some ESC's have a couple of brake settings - like hard, soft or none. The same torque issues obtain for turn on as well and again some ESC's have a soft turn on setting too.
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Old Dec 05, 2012, 11:14 AM
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Originally Posted by Greywing View Post
Ory: Keep in mind that if you disable the brake, your motor will windmill when you shut it down causing a lot of drag and compromising your glide performance. Some ESC's have a couple of brake settings - like hard, soft or none. The same torque issues obtain for turn on as well and again some ESC's have a soft turn on setting too.
Absolutely true!

I normally set soft brake and soft start. Takes some of the load off the motor and the motor mount.
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Old Dec 05, 2012, 12:18 PM
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Power off dive problem

I, like many others, have had issues with the 'power off dive' problem. It seems if you trim it so it flies level with a little power, and doesn't climb straight up when you throttle up, it dives down pretty quickly when power is turned off. I'll also add that my CG is right where the manual says it should be. I initially raised the horizontal stab by putting down some hot glue on the aft end of the vertical's slot. This helped some, but still didn't get things to where I want them. To get it to glide gracefully with throttle off I still had to have about an 1/8 inch or so of up elevator trim. It's beautiful to watch it glide so nice with no power and NOT having to feed in any elevator. But.....when it is trimmed like this, when you give it any throttle to climb you have to keep putting in down elevator to keep it from going straight up. So, I tried to minimize the problem by creating a throttle to elevator mix. This is not a cure all, and it may take several launches to get it right, but it seems to be helping me fly it like I want to. Just add in a small % of elevator down into the throttle....then with power off it will glide nicely without having to feed in much up elevator, and when you power up, it will not point it's nose straight up.

If you try this method, be sure you know how it reacts to all flying positions...i.e. power off turns, half throttle and full throttle turns, inverted, etc.

Again, this is not a perfect workaround....but it works for me.....

Another option would be to put in a 2 or 3 axis gyro. That would control the climb and glide of the aircraft with minimal stick input.....

Mike
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Old Dec 05, 2012, 12:23 PM
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Hi, rivanna.

I was able to fix the motor mount, after an impact, by carefully gluing the cracks and doubling the mount. I used 1/32" plywood and a layer of Skyloft (which is basically really thin fiberglass cloth) and CA. So far it has held up.

Ory. I'm with the other guys. In fact, I would say that soaring is impossible with a windmilling prop. You would actually be better off with a fixed blade prop with the brake on than a folding prop with the brake off. Remember. A stationary prop creates drag proportional to the area of the blade. A windmilling prop creates drag proportional to the area of the disk. That's why a helicopter doesn't need blades of the same area as a wing capable of the same amount of lift.

Cheers!
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Old Dec 05, 2012, 03:27 PM
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Originally Posted by aclinml View Post
I, like many others, have had issues with the 'power off dive' problem. It seems if you trim it so it flies level with a little power, and doesn't climb straight up when you throttle up, it dives down pretty quickly when power is turned off. I'll also add that my CG is right where the manual says it should be. I initially raised the horizontal stab by putting down some hot glue on the aft end of the vertical's slot. This helped some, but still didn't get things to where I want them. To get it to glide gracefully with throttle off I still had to have about an 1/8 inch or so of up elevator trim. It's beautiful to watch it glide so nice with no power and NOT having to feed in any elevator. But.....when it is trimmed like this, when you give it any throttle to climb you have to keep putting in down elevator to keep it from going straight up. So, I tried to minimize the problem by creating a throttle to elevator mix. This is not a cure all, and it may take several launches to get it right, but it seems to be helping me fly it like I want to. Just add in a small % of elevator down into the throttle....then with power off it will glide nicely without having to feed in much up elevator, and when you power up, it will not point it's nose straight up.

If you try this method, be sure you know how it reacts to all flying positions...i.e. power off turns, half throttle and full throttle turns, inverted, etc.

Again, this is not a perfect workaround....but it works for me.....

Another option would be to put in a 2 or 3 axis gyro. That would control the climb and glide of the aircraft with minimal stick input.....

Mike
If you are using a radio with flight modes/conditions you can set the trim for each flight condition you are experiencing. Needing different trim settings is common for launching, cruising, thermaling, and landing. In other words, this is not a negative attribute of the Calypso.

-Randy
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Old Dec 05, 2012, 03:41 PM
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I concur with Westranm. Any plane with a lifting airfoil and low thrust line will climb under power. As one increases speed the wing increases lift faster than the horizontal stabilizer. Having learned to fly long before anyone thought of mixing radios, or electric gliders for that matter, I just expect to hold a little bit of down elevator when I hit the throttle. Another trick is to launch at partial throttle and slowly apply power. A gradual increase in speed allows the stab to "catch up" with the wing.
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Old Dec 05, 2012, 05:54 PM
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Originally Posted by aeajr View Post
Absolutely true!

I normally set soft brake and soft start. Takes some of the load off the motor and the motor mount.
I know folks differ on this & their 'practices' re brake function - but I don't fly well enough for the perhaps 1/2-to-1 second the prop spins before folding, to really affect my plane's performance. Folded props don't freewheel, & if they do, the shoulder screws are too tight. \_(?)_/

Diff'rent strokes.
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Old Dec 06, 2012, 09:24 AM
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Caso Motor Mount

Peterlingh & Starhopper--Peter-I used your mount fix based on what you said in #264 and which you just expanded upon above, Thank you--it seems to work on the bench! Star -I bought the Arf version and used electronics I had on hand except I had to buy the motor from Tower.As far I know, it is the only one that fits. That is the reason I had a good look at the "crappy"plastic mount. Good flying and Merry Christmas! Rivanna.
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Old Dec 06, 2012, 11:24 AM
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Along the theme of power on and power off shock loading the motor mount...

I like to keep the throttle on the left stick rather than on an off/on type switch. That way I can control the speed of the motor on start and how fast the motor is turning when the brake kicks on. Gentle with the turn on and gentle on the turn off = much easier loads for the airframe and motor to carry.
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Old Dec 07, 2012, 07:29 AM
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Originally Posted by Westranm View Post
If you are using a radio with flight modes/conditions you can set the trim for each flight condition you are experiencing. Needing different trim settings is common for launching, cruising, thermaling, and landing. In other words, this is not a negative attribute of the Calypso.

-Randy
Actually, I have a fairly new DX8 and thought about the very same thing. Upon trying to set it up, it appears the Flight Mode switch only works with helis, not fixed wing craft......
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Old Dec 07, 2012, 07:45 AM
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DX8 is a great radio with lots of features but not really set-up for gliders. No glider programming so you have to use airplane programs to fly gliders.
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Old Dec 07, 2012, 01:27 PM
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Originally Posted by aeajr View Post
DX8 is a great radio with lots of features but not really set-up for gliders. No glider programming so you have to use airplane programs to fly gliders.
Agree. If you want proper support for sailplanes and want to stay with Spektrum, the DX18 is currently the option. Or, if you are ok with no telemetry in your transmitter and want to stick with DSMX, go with a JR radio supporting DSMX. I went a step further and adopted JR's new DMSS technology that has features and lightweight telemetry more suitable to sailplanes.

-Randy
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Old Dec 07, 2012, 01:29 PM
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Which JR did you get?
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Old Dec 07, 2012, 01:30 PM
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Originally Posted by JimNM View Post
Along the theme of power on and power off shock loading the motor mount...

I like to keep the throttle on the left stick rather than on an off/on type switch. That way I can control the speed of the motor on start and how fast the motor is turning when the brake kicks on. Gentle with the turn on and gentle on the turn off = much easier loads for the airframe and motor to carry.
Many ESC have variable brake settings. When possible I set for soft start and soft brake.

But even if you are on hard brake, the stock motor on teh stock mount should be fine. Now, if you have put in Gigantor the Wonder Motor, then you need to be concerned about that motor mount.
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Old Dec 07, 2012, 03:31 PM
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Originally Posted by aeajr View Post
Which JR did you get?
I have started with the XG6 to try it out--it has worked well. I am about to set up a DLG and a sloper with the same. Once Horizon manages to get an inventory of the XG11 with a proper mode 2 switch layout, I'm planning to get one.

I posted details on how i am using this radio with the Calypso elsewhere on RC Groups. If your interested I can send you a link later.

-Randy
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