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Old Nov 18, 2012, 12:30 AM
Registered User
United States, WI, Appleton
Joined Jul 2010
236 Posts
Moby, Awesome! Sounds like a great time.

Sam

Re: errors. I don't think 10 mph is too much for the RP, although maybe for first flight it's a bit on the high side. But once it got up in the air that shouldn't have been much of an issue.
CG. 2.75 is about 70 mm, which is right on the recommended position.
Battery sliding could be bad, but I can't believe it would be too big a deal unless it was moving an inch or so.
Sorry I can't really think of why your RP was so touchy, unless the previous owner liked a sensitive airplane.

Re: prop. The 'good' stock prop has 9.75X7.5_1 molded on the hub, not printed on. Lot's of folks on this forum have changed props, I'm cheap, so I still use this prop.

Re: transportation. I can barely fit mine in my minivan assembled. You might search the forum for wing attach mods. Mine uses a d-sub connector so I can just plug the wings in without wrestling with the servo leads. There are a couple of mods that are better than mine, though, as far as weight and simplicity are concerned.
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Old Nov 18, 2012, 01:58 AM
A geriatric flier
Watdazit's Avatar
Australia, NSW, Braidwood
Joined Nov 2008
792 Posts
Quote:
Originally Posted by samhoff View Post
.........it was a little windy, I'll say about 10 mph.......... Balanced about 2.75 inches behind front of wing, using the "stock" battery that the guy sent me with the RP (Parkzone 11.1, 1300).]

......... From there on it was a wild west rodeo! Up down, down up, serve left, swerve right! Lots of porpoising, and a little flying backwards (relative to ground speed)...................Interestingly on the final approach, with throttle OFF, all the sudden the prop started whirring (about 1/2 throttle) and then shut off after about 4 seconds.
Hi Sam.

Firstly you know it's too windy when you have to lean into it. 10 kph is nothing. I will fly in 20 kph gusting to 30 kph. The Radians will take that. A bit bouncy aloft but OK.

You said you did a throw glide test but before it finished you powered on. Glide tests are best done in no wind.

If it was porpoising under power then forget it. You are only going to power up until you reach an adequate height and then power off. Does it porpoise with no power when you are gliding. If so it could be a balance problem. It's interesting you say the battery was loose. Mine is as tight as hell and I had to remove the velcro to get the battery in. They do wedge between top and bottom and if yours isn't put some extra velcro or foam on the battery. Watch when you are gliding (no power) on a reasonable calm day. If it tends to nose down it could be heavy on the front but it could also be the elevator needs trimming. Likewise if the plane rises is could be heavy on the rear or again the elevator might need trimming.

With your ESC worries rebind it and do your throttle end points again. See if that fixes it. I cannot remember if the standard ESC has a "soft" brake on them. If they do that might also cause the prop to spin a bit before it stops.

You say it was like a rodeo ride. What DR's and expo are you running. On take off under power I run 40 Expo and 70 DR on the ailerons and 40/80 on the elevator and rudder. When I am gliding I mostly go to 40/100 all around. I find on take off I can hold the RP aloft and go to about 3/4 power and she just rises beautifully out of my hand with a slight push. I do not have to throw it. It could also be the old clenched bum syndrome. Relax.

Also make sure all the servos are working smoothly with no binding.

After all this then have a beer and you will feel much better.
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Old Nov 18, 2012, 01:52 PM
I did it...
av8ersteve's Avatar
Morganton, NC
Joined Jun 2005
756 Posts
Hey all, gota question. Is this battery "Puffed"? I really didn't notice until I got another battery. It does good in my RP and I have never heated it up. It just looks and feels a little different than the new one. Can I keep using it, or no? Thanks in advance.
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Old Nov 18, 2012, 02:20 PM
Tossing planes into the snow
Canada, BC, Smithers
Joined Nov 2011
2,877 Posts
Do both of them weigh the same? I have noticed some variations in size and weight with these batteries.
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Old Nov 18, 2012, 02:25 PM
A geriatric flier
Watdazit's Avatar
Australia, NSW, Braidwood
Joined Nov 2008
792 Posts
Quote:
Originally Posted by av8ersteve View Post
Hey all, gota question. Is this battery "Puffed"? I really didn't notice until I got another battery. It does good in my RP and I have never heated it up. It just looks and feels a little different than the new one. Can I keep using it, or no? Thanks in advance.
It certainly looks a "little" puffed but it is hard sometimes to tell if it is on the way out and should be pierced and disposed of. Age and use is not always a barometer of a battery's tendency to puff. I have some batteries which puffed like yours within a month of purchase but they have been performing OK for me for 12 months. I have one Outrage battery which is 5 years old and puffed and still works OK. I have had a fairly new 1300 3S Dualsky battery with no indication of puffing going up in flames inside a foam Skysurfer and wrecking it.

I usually find they may be puffed a little but stay that way with no change and are OK. If the puffing goes up and down then it may be the sign of a problem, so get rid of it (and this is contrary to what a lot of people say). If the puffing keeps getting worse then get rid of it. As it is now as long as you store it safely I would say it's OK.

I think puffing has an effect on performance but on a glider this may not be a problem unless you are in a competition looking for max height in a short burst.
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Old Nov 18, 2012, 03:08 PM
A geriatric flier
Watdazit's Avatar
Australia, NSW, Braidwood
Joined Nov 2008
792 Posts
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Originally Posted by Jovanx View Post
Do both of them weigh the same? I have noticed some variations in size and weight with these batteries.
So what is the effect of the weight difference, I think you need to say.

I would assume a battery undergoing chemical change can loose weight however this should only happen if the battery has been pierced and gases allowed to escape. That battery being exposed to the air is going to go up in smoke anyway. If the battery remains sealed surely there should be no weight change and "might" remain useful.

I am not sure if a hot battery might loose weight through the energy generated but I am also not sure if the chemical change causing the heat will mean the battery will get lighter. Something from school about matter not being created or destroyed.
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Old Nov 18, 2012, 03:16 PM
Tossing planes into the snow
Canada, BC, Smithers
Joined Nov 2011
2,877 Posts
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Originally Posted by Watdazit View Post
So what is the effect of the weight difference, I think you need to say.
I guess my post was a little misleading. Batteries don't change their weight when they get old, as far as I know. What I was referring to is that the new one you bought might not be the same size and weight as the old one. There is some variation in their products.

If you look at the end where the wires come out you will either see some white fiber tape inside the green outer cover, or you will see some gold foil. Those 2 batteries look the same at a glance but are different in weight and longevity. Both are Parkzone 1300 mah 3c 15c batteries.
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Old Nov 18, 2012, 03:39 PM
I did it...
av8ersteve's Avatar
Morganton, NC
Joined Jun 2005
756 Posts
Thanks guys. Both batts have the gold looking foil. I do not have a way to weigh them right now but I think I'm going to work on that. I don't want to throw away a good battery if there is nothing wrong with it, but I also don't want to loose my RP in a "Blaze of Glory". I think I will continue using it under a close eye, only use it as my spare, and if it changes at all, dispose of it properly. Thanks.
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Old Nov 18, 2012, 04:12 PM
Gopher huntin' stick jockey
turboparker's Avatar
East Bethel, MN USA
Joined Jul 2009
11,533 Posts
Quote:
Originally Posted by av8ersteve View Post
Hey all, gota question. Is this battery "Puffed"? I really didn't notice until I got another battery. It does good in my RP and I have never heated it up. It just looks and feels a little different than the new one. Can I keep using it, or no? Thanks in advance.
Has the pack ever been flown to LVC. If so, how many times? Also - how many cycles are on the pack? The #1 cause of early pack failure nowadays is discharging them beyond 80%. Many non-adjustable LVC circuits are set way too low, which kills packs. The PZ packs usually only last for 30 cycles or so before they start to fade away - even when pampered.

Keeping a close eye on the pack & getting rid of it if anything changes is a good idea.

Joel
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Old Nov 18, 2012, 11:49 PM
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Joined Sep 2010
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Quote:
Originally Posted by turboparker View Post
Has the pack ever been flown to LVC. If so, how many times? The PZ packs usually only last for 30 cycles or so before they start to fade away - even when pampered.

Joel
The gold foil packs seem to be weaker than the tape style. Others have reported the difference between them. Neither type is top quality. After a year of use, with tender care and feeding, they'd faded, badly. They'll get you started flying our RP. Don't expect them to work well using an after-market prop.
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Old Nov 19, 2012, 12:08 AM
Dixie Normious
Eastcoast78's Avatar
Can A da....Ehh!!
Joined May 2010
5,317 Posts
well tomorrow is FPV day with my old RP...GoPro on a standard Servo hot glued in to some pink foam...
Also hot glued 2 strips of Velcro on the foam as to hold it to the fuse(no canopy)

I wanted to have it Y'd to Rudder but it was reversed unless i turned the servo upside down?
So i Y'd it to the Aileron. Seems like its going to be pretty cool...fingers crossed hehe

A scale looking flight deck with mock gauges etc is in the works with pilot figure like i posted awhile ago. This is just a test and something to mess with tomorrow..location is here...this was from today..but not with RP.
TBRC Cold and windy!! (10 min 35 sec)
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Old Nov 19, 2012, 11:05 AM
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samhoff's Avatar
Sheridan, WY, USA
Joined Jul 2003
248 Posts
First flight of RP with GoPro Hero2 on top

Here it is. I couldn't get much elevation; seemed pretty underpowered. And listen to the prop; I thought it sounded a little funny. ESC issues?

I think the earlier issue (porpoising) may have been a binding rod on the elevator; I will polish soon.

Thanks for any and all feedback. Interestingly I never understood the term "wing tip stall" but I do now!

Sam

First flight of the Radian Pro with GoPro Hero2 on top (4 min 55 sec)
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Old Nov 19, 2012, 11:51 AM
Drifting off the reservation..
JumpySticks's Avatar
USA, LA, Broussard
Joined Jan 2011
2,293 Posts
Quote:
Originally Posted by samhoff View Post
Here it is. I couldn't get much elevation; seemed pretty underpowered. And listen to the prop; I thought it sounded a little funny. ESC issues?

I think the earlier issue (porpoising) may have been a binding rod on the elevator; I will polish soon.

Thanks for any and all feedback. Interestingly I never understood the term "wing tip stall" but I do now!

Sam

http://www.youtube.com/watch?v=FCz1S...ature=youtu.be
Sounds like low voltage cut off to me. However, it usually will not run that long. Maybe you have a bad connection to the battery??? You're definitely not getting full power to the motor.
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Old Nov 19, 2012, 12:00 PM
Registered User
United States, TN, Johnson City
Joined Jul 2011
185 Posts
Quote:
Originally Posted by samhoff View Post
Here it is. I couldn't get much elevation; seemed pretty underpowered. And listen to the prop; I thought it sounded a little funny. ESC issues?

I think the earlier issue (porpoising) may have been a binding rod on the elevator; I will polish soon.

Thanks for any and all feedback. Interestingly I never understood the term "wing tip stall" but I do now!

Sam

http://www.youtube.com/watch?v=FCz1S...ature=youtu.be
I agree. Sounds like you are near the LVC, but i don't understand how you could run that long if it was. Be sure your battery is fully charged and in good condition. It is a good Idea to also check your prop adapter and spinner fasteners to be sure they are tight. It seemed to me you were losing altitude pretty fast when you shot off the motor. Have you done glide tests to be sure you are not nose heavy??
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Old Nov 19, 2012, 12:24 PM
Tossing planes into the snow
Canada, BC, Smithers
Joined Nov 2011
2,877 Posts
In addition to an undetermined power problem, it sounds like there is some vibration coming from the motor. It could be due to the motor mount screws being loose, the firewall not being solidly attached to the fuse, a bent motor shaft from a previous hard landing, or just dirt stuck inside the prop adapter or in the slots in front of the props. Mine sounds like that when I get snow jammed in there and it all goes out of balance.

The elevator on this plane is super-sensitive, especially if you move the CG back. When it is flying under power, it is even more sensitive. If you are planning on flying under power most of the time, I would suggest going for minimum elevator throws and some expo to boot. I fly mine as a glider, and it takes longer to get up to height with a 6 oz camera attached, but it eventually gets there.

Here is my method for trimming the RP for onboard video. It takes a bunch of short flights where you just take it up to tree top level and cut the power. That way the plane is close and it is easy to see what it is doing. Then it is a matter of experimenting with elevator trim and tail weights until it will GLIDE hands-free without porpoising. Then you can send it way up there and kill the motor and know it is not porpoising. I like to keep my hands off the sticks as much as possible to get smoother video. Only when it is starting to get far away, I use just a bit of rudder to gradually turn it around towards me.
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