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Old Sep 18, 2012, 11:05 AM
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Danny_l's Avatar
South Africa, WC, Cape Town
Joined Oct 2011
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Hi Peter,
Thanks.

The ESC is not set to brake, but I don't see how a folded prop can windmill.
(I set it to brake on all other electric planes)
Regarding the porpoising, I don't think that it was a matter of trying to fly it too slow.

If a plane is built and trimmed correctly, even when you fly it slow to the point of stalling it should then drop the nose (except tip-stalls in war-birds and certain aerobatic planes) and when it regains enough speed if it "shoots" up it means that there is too much up-elevator trim.

I do want to get this glider to work a my son is very keen to fly it (we fly power models every weekend) and I'll persist. However, IMO a plane that needs so many mods just to be able to fly is not something I'll recommend to anyone ...
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Old Sep 18, 2012, 11:14 AM
Bye Bye VP Aug 2010 - Aug 2012
Gerry__'s Avatar
United Kingdom, London
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Quote:
Originally Posted by Danny_l View Post

I do want to get this glider to work a my son is very keen to fly it (we fly power models every weekend) and I'll persist. However, IMO a plane that needs so many mods just to be able to fly is not something I'll recommend to anyone ...
Mine flies fine without mods. There are enough videos on the net to prove that the RP performs well, so it could well be a problem with your one, or just that you're unable to get the best out of it. The later could be skill or conditions related.
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Old Sep 18, 2012, 11:39 AM
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United States, VT, Rutland
Joined Dec 2011
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I'm a newbie and had only 3 flights with a 4-channel plane before I got my RP.
I had some porpoising my 1st flight (stock LiPo) and this newbie was lucky to get it on the ground in one piece.
I moved the LiPo back as far as I could and it glides hands-off now.
I wish I had some info. to help you. It really is a fun plane.
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Old Sep 18, 2012, 12:01 PM
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United States, TN, Johnson City
Joined Jul 2011
187 Posts
Quote:
Originally Posted by Danny_l View Post
Hi Peter,
Thanks.

The ESC is not set to brake, but I don't see how a folded prop can windmill.
(I set it to brake on all other electric planes)
Regarding the porpoising, I don't think that it was a matter of trying to fly it too slow.

If a plane is built and trimmed correctly, even when you fly it slow to the point of stalling it should then drop the nose (except tip-stalls in war-birds and certain aerobatic planes) and when it regains enough speed if it "shoots" up it means that there is too much up-elevator trim.

I do want to get this glider to work a my son is very keen to fly it (we fly power models every weekend) and I'll persist. However, IMO a plane that needs so many mods just to be able to fly is not something I'll recommend to anyone ...
It should fly reasonably well out of the box. I have an RP and am soon to be on my third Radian. The RP can be a handful to a new glider pilot. You might be happier starting with the Radian to get some experience before the RP. If you are expecting a slow flying/floating experience, the RP is not your first choice. What radio are you using ?? Do you have flaps/crow/reflex/camber set up?? Do you know what each is for and how to use them?? My RP has a CG at 86mm with an AUW of 38.5 oz. That includes a metal spinner, larger prop, boom and vertical fin stiffening carbon, 1300mah battery and 1oz of wt on the tail. It glides with essentially no trim in still air. It needs down trim and/or a larger battery for windy conditions.. I learned this thru experience and info from the forum, but I am not sure it is best for a new pilot.
You should take yours out for some hand glide tests with no trim. It should glide easily with a hand toss and settle to the ground w/o nosing in or stalling. It it stalls it is too taill heavy and if it noses in it is too nose heavy. Add wt where needed and then try it from there. Actual flying conditions will dictate how it should be trimmed - a little up or down trim.
All this should be possible w/o any mods. After you get some experience, the mods may improve your fun factor. Best of luck!
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Old Sep 18, 2012, 12:12 PM
Drifting off the reservation..
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USA, LA, Broussard
Joined Jan 2011
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Quote:
Originally Posted by Danny_l View Post
Thanks kaptondave,
this is a very informative video. so in essence the RP is a poorly designed and badly assembled glider that needs considerable modification in order to fly as a glider should.
I find this surprising and in contrast to other PZ planes that I have and fly very well as they come. (T28 and P47)

I'll do the modifications and try again.

Brgds,

Danny
Danny,

Try it with a stock 1300 ma battery. I missed that in your OP, that you were flying a big battery. With a stock 1300 ma battery all the way back it should balance at about 77mm from leading edge and should trim with neutral elevator to fly nice and slow.
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Old Sep 18, 2012, 12:18 PM
Drifting off the reservation..
JumpySticks's Avatar
USA, LA, Broussard
Joined Jan 2011
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Quote:
Originally Posted by Brian VT View Post
I'm a newbie and had only 3 flights with a 4-channel plane before I got my RP.
I had some porpoising my 1st flight (stock LiPo) and this newbie was lucky to get it on the ground in one piece.
I moved the LiPo back as far as I could and it glides hands-off now.
I wish I had some info. to help you. It really is a fun plane.
I remember when I bought my first RP thinking it was a real dog the first few sessions. She's a complex lady, and takes some getting used to. That complexity keeps her interesting, even after nearly 2 years.
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Old Sep 18, 2012, 12:40 PM
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United Kingdom, London
Joined Mar 2012
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Quote:
Originally Posted by JumpySticks View Post
Danny,

Try it with a stock 1300 ma battery. I missed that in your OP, that you were flying a big battery. With a stock 1300 ma battery all the way back it should balance at about 77mm from leading edge and should trim with neutral elevator to fly nice and slow.
hmmm, my 1300 mah battery is positioned to the edge of the foam ledge (1inch forward of all the way back). Plane balances level on CG point. Have never tried it all the way back.......... might check it out.
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Old Sep 18, 2012, 01:37 PM
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South Africa, WC, Cape Town
Joined Oct 2011
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First, thanks to all who are trying to help, I'll try and answer your questions of me here.

Next, Gerry: I've already commented on your sarcastic remarks. keep them to yourself please.

1. Sadly in SA most kits come with less than in the US. the RP came without a battery and I have several 2200mah packs, so I'll have to make do with them and if necessary use weight to balance it.
2. my TX is a DX8.
3. I know what Reflex, Camber and Crow are, but have not programmed these yet. I first want the glider to fly as is. (these mixes are to enhance flight, not to fix inherent problems)

I am not interested in 3 channel planes, so all the gliders in that category were never a consideration.

I've been back with RC flying for a year after a long break, but fly an average of 12 flights a week, every week so I'm hardly a new pilot.


Eagle, I was going to try and set the CG at 90mm as per the video, and see how it goes from there.

Thanks and best Regards,

Danny
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Old Sep 18, 2012, 02:10 PM
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United States, TN, Johnson City
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Quote:
Originally Posted by Danny_l View Post
First, thanks to all who are trying to help, I'll try and answer your questions of me here.

Next, Gerry: I've already commented on your sarcastic remarks. keep them to yourself please.

1. Sadly in SA most kits come with less than in the US. the RP came without a battery and I have several 2200mah packs, so I'll have to make do with them and if necessary use weight to balance it.
2. my TX is a DX8.
3. I know what Reflex, Camber and Crow are, but have not programmed these yet. I first want the glider to fly as is. (these mixes are to enhance flight, not to fix inherent problems)

I am not interested in 3 channel planes, so all the gliders in that category were never a consideration.

I've been back with RC flying for a year after a long break, but fly an average of 12 flights a week, every week so I'm hardly a new pilot.


Eagle, I was going to try and set the CG at 90mm as per the video, and see how it goes from there.

Thanks and best Regards,

Danny
I see the CG as an outcome rather than something you are trying to shoot for. I work to get the plane gliding smoothly by adding wt and trim as needed and then I may see where the cg is, but I really am not interested in that number other than as a curiosity! This is a different ballgame vs powered RC planes as to CG.
As others have pointed out, after you get it gliding well, powered flt can be another challenge!
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Old Sep 18, 2012, 02:17 PM
Bye Bye VP Aug 2010 - Aug 2012
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United Kingdom, London
Joined Jan 2005
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Originally Posted by Danny_l View Post
Next, Gerry: I've already commented on your sarcastic remarks. keep them to yourself please.
No sarcasm here, just honesty. A number of us have told you the RP isn't intrinsically bad and that you should get good results out of the box, but inspite of this and your lack of glider experience, you insist it needs mods. You have a good radio, but for some reason you haven't set it up fully for the RP. In the world of full house gliders you are expected to get your Tx sorted. You need to put much more effort in before you qualify to pass judgment, IMO. Not least, you need to learn how to find and utilise lift.

Your starting point should be to fly it stock, and that includes the correct battery. Putting in a 2200 and then criticing the sink rate really isn't playing fair.
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Old Sep 18, 2012, 02:24 PM
Bye Bye VP Aug 2010 - Aug 2012
Gerry__'s Avatar
United Kingdom, London
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Quote:
Originally Posted by eagle1960 View Post
I see the CG as an outcome rather than something you are trying to shoot for. I work to get the plane gliding smoothly by adding wt and trim as needed and then I may see where the cg is, but I really am not interested in that number other than as a curiosity! This is a different ballgame vs powered RC planes as to CG.
As others have pointed out, after you get it gliding well, powered flt can be another challenge!
I would say that powered flight really is but one mode with the RP, ie full power and up. I never run my motor for more than 30-seconds and never run it on partial throttle for more than a couple of seconds.
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Old Sep 18, 2012, 02:45 PM
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Hi again, Danny.

A folding prop will continue to windmill without the brake and said windmilling will kill any chance of a good glide performance. Remember; a prop is just a wing that spins and unless one brakes a folding prop the lift on that "wing" will keep the blades extended. I would suggest trying that one change before trying anything else. Another thing to keep in mind with a glider or anything with a high lift airfoil is that any change in airspeed will have a big effect on trim. I can't stress enough that "the faster you go the more it wants to climb". This is exacerbated by a windmilling prop.

The wing will seek it's preferred glide speed and angle. With a windmilling prop it will drop the nose more than necessary to compensate for the drag then, when it's going fast enough to self correct, it will lose speed and lift faster than wanted.

Keep asking questions and good luck!
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Old Sep 18, 2012, 02:53 PM
Bye Bye VP Aug 2010 - Aug 2012
Gerry__'s Avatar
United Kingdom, London
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Originally Posted by peterlngh View Post
Hi again, Danny.

A folding prop will continue to windmill without the brake and said windmilling will kill any chance of a good glide performance. Remember; a prop is just a wing that spins and unless one brakes a folding prop the lift on that "wing" will keep the blades extended. I would suggest trying that one change before trying anything else. Another thing to keep in mind with a glider or anything with a high lift airfoil is that any change in airspeed will have a big effect on trim. I can't stress enough that "the faster you go the more it wants to climb". This is exacerbated by a windmilling prop.
I couldn't agree more.
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Old Sep 18, 2012, 03:30 PM
Never enough time to fly!
ecase's Avatar
SLC, UT
Joined Sep 2006
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Hey Gerry__ why can't we quote you?

"No sarcasm here, just honesty. A number of us have told you the RP isn't intrinsically bad and that you should get good results out of the box, but inspite of this and your lack of glider experience, you insist it needs mods. You have a good radio, but for some reason you haven't set it up fully for the RP. In the world of full house gliders you are expected to get your Tx sorted. You need to put much more effort in before you qualify to pass judgment, IMO. Not least, you need to learn how to find and utilise lift.

Your starting point should be to fly it stock, and that includes the correct battery. Putting in a 2200 and then criticing the sink rate really isn't playing fair."

Amen, set it up fully and give the plane a fair shot before you pass judgment.
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Old Sep 18, 2012, 03:36 PM
Bye Bye VP Aug 2010 - Aug 2012
Gerry__'s Avatar
United Kingdom, London
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Originally Posted by ecase View Post
Hey Gerry__ why can't we quote
I've picked up some infractions for telling people they were 'talking rubbish'.
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