Wing rock problems.
04-06-2007 | 01:58 PM
#1
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From: Wareham, UNITED KINGDOM
Wing rock problems.
I test flew my Bad Boy V2 today and generally it went OK but not brilliant.
The main problem was severe wing rock in the harrier and hover.
C/g as per instructions.
Max movement on all surfaces.
60% expo.
53 2 stroke / 13x4 APC prop.
The model will do awesome inverted climbing flat spins, but..... Hover is terrible due to the wing rock.
Anybody any ideas as to the cause.
Many thanks
Simon
The main problem was severe wing rock in the harrier and hover.
C/g as per instructions.
Max movement on all surfaces.
60% expo.
53 2 stroke / 13x4 APC prop.
The model will do awesome inverted climbing flat spins, but..... Hover is terrible due to the wing rock.
Anybody any ideas as to the cause.
Many thanks
Simon
04-06-2007 | 05:03 PM
#3
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My Feedback: (14)
RE: Wing rock problems.
Before you go messing with spoilers......if your Transmitter has the function, you should dial in about 40 to 60% exponential!! If you're using a Futaba system...thats negative 40 to 60%...
Expo will slow down your over control/correction problem that is causing the wing rocks!!
You will thank me later!!
Expo will slow down your over control/correction problem that is causing the wing rocks!!
You will thank me later!!
04-06-2007 | 07:19 PM
#5
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RE: Wing rock problems.
DAAAAAA..........He did'nt say what kind of radio he was running, and if he dialed POSITIVE 60% on a Futaba system, That would certainly be the cause of his problems...too sensitive at center!!
Futaba Expo Needs To Be NEGATIVE!!
Futaba Expo Needs To Be NEGATIVE!!
04-06-2007 | 08:27 PM
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From: PTY, , PANAMA
RE: Wing rock problems.
Simon, I recommend to move the cg farther aft, and try testing lateral CG, I'm not using any type of mixes on mine. Here is a few vids of mine, no wingrock at all, maybe you need less or more elevator throw???
http://www.aerofun3d.com/videos/fgvcglow_aerofundan.wmv
http://www.aerofun3d.com/videos/BB1.wmv
http://www.aerofun3d.com/videos/skycambbp.wmv
http://www.aerofun3d.com/videos/fgvcglow_aerofundan.wmv
http://www.aerofun3d.com/videos/BB1.wmv
http://www.aerofun3d.com/videos/skycambbp.wmv
04-06-2007 | 10:25 PM
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From: Wareham, UNITED KINGDOM
RE: Wing rock problems.
Thanks for the help so far. I have moved the c/g back a bit and carefully checked the lateral balance again....added some weight to the l/h wing to balance it evenly inverted. Time for another test flight!.
Why on earth would I want to cut the wing tips off???!!!
Why on earth would I want to cut the wing tips off???!!!
04-06-2007 | 11:16 PM
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From: The Woodlands,
TX
RE: Wing rock problems.
It takes out the wing rock in profiles and helps the knife edge. The wing tips are there for stabilty, in a 3D plane, you don't want it to be stable.
Try all the other stuff first, if that does not work, cut the tips off. Mine harriers fine, however I never flew it with the tips on, they were removed when th plane was built.
Try all the other stuff first, if that does not work, cut the tips off. Mine harriers fine, however I never flew it with the tips on, they were removed when th plane was built.
04-07-2007 | 02:32 AM
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From: Colorado Springs,
CO
RE: Wing rock problems.
ORIGINAL: YNOT
Cut the wing tips off.
Cut the wing tips off.
Make sure your expo is at a negative value if you have a futaba most importantly!!!
04-07-2007 | 02:58 AM
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From: Colorado Springs,
CO
RE: Wing rock problems.
However judging from the 3 video's above and this 1 http://www.eldonmo.com/video/2006_mcddd_video2.wmv the tip's actually keep the Bad Boy more stable in a normal harrier/hover/flat spin.
So you might want to keep your tips until you can harrier/hover very easy. Then if you deside you want to change the performance clip those wings for a wild ride.
So you might want to keep your tips until you can harrier/hover very easy. Then if you deside you want to change the performance clip those wings for a wild ride.
04-23-2007 | 10:46 PM
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From: Muscle Shoals, AL
RE: Wing rock problems.
Wing rock is usually caused by the wing lifting and stalling in a rapid manner. The wing stalls and drops, picks up speed on the drop, lifts, and stalls again. The stalled wing drops behind the wing still flying, causing the flying wing to accelerate. The whole thing causes the plane to yaw. As you correct the stalled wing, you then stall the wing that was flying. That sets in motion the series of rapid stalls and recoveries that is wing rock. For a harrier you want the wing completely stalled, just as in an elevator. Move the cg back or increase throw in the elevator.
Curtis
Curtis
04-24-2007 | 07:10 AM
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From: Brisbane, AUSTRALIA
RE: Wing rock problems.
Cut off those tips, it doesn't get any simpler than that. My CG is at 165mm back has been since day 1.
I had the wingtips on for the first...30 flights. The I bought a Katana P and have not flown my Bad Boy since June 2006 until this past Sunday..after I cut the wingtips off (and I'm not one to leave planes at home for long)
The plane is a totally different machine now. It used to have wing rock like you would not beleive and never had that "locked in" feeling in any high alpha like my Katana does.
Without the wingtips it will harrier with very minimal wing rock (still not as little as my Kat) and the hovers have a much more controllable and locked in feeling. It will actually flatspin properly now too, almost push into a climbing flatspin.
Now I will actually have to make a concious thought about which plane to take to the field, have to stop instinctively grabbing the Kat
I wouldnt bother messing around with the CG and annoying computer mixes to try and fix it, set your CG a small amount aft of reccomended cut the tips off and thats it.
EDIT: That is my V1 in my avatar which now resides in the roofspace
it has served me well...the V2 is the plane I was referring to.
I had the wingtips on for the first...30 flights. The I bought a Katana P and have not flown my Bad Boy since June 2006 until this past Sunday..after I cut the wingtips off (and I'm not one to leave planes at home for long)
The plane is a totally different machine now. It used to have wing rock like you would not beleive and never had that "locked in" feeling in any high alpha like my Katana does.
Without the wingtips it will harrier with very minimal wing rock (still not as little as my Kat) and the hovers have a much more controllable and locked in feeling. It will actually flatspin properly now too, almost push into a climbing flatspin.
Now I will actually have to make a concious thought about which plane to take to the field, have to stop instinctively grabbing the Kat
I wouldnt bother messing around with the CG and annoying computer mixes to try and fix it, set your CG a small amount aft of reccomended cut the tips off and thats it.
EDIT: That is my V1 in my avatar which now resides in the roofspace
it has served me well...the V2 is the plane I was referring to.
04-24-2007 | 12:57 PM
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From: Muscle Shoals, AL
RE: Wing rock problems.
ORIGINAL: Fly-guy
Cut off those tips, it doesn't get any simpler than that. My CG is at 165mm back has been since day 1.
I had the wingtips on for the first...30 flights. The I bought a Katana P and have not flown my Bad Boy since June 2006 until this past Sunday..after I cut the wingtips off (and I'm not one to leave planes at home for long)
The plane is a totally different machine now. It used to have wing rock like you would not beleive and never had that "locked in" feeling in any high alpha like my Katana does.
Without the wingtips it will harrier with very minimal wing rock (still not as little as my Kat) and the hovers have a much more controllable and locked in feeling. It will actually flatspin properly now too, almost push into a climbing flatspin.
Now I will actually have to make a concious thought about which plane to take to the field, have to stop instinctively grabbing the Kat
I wouldnt bother messing around with the CG and annoying computer mixes to try and fix it, set your CG a small amount aft of reccomended cut the tips off and thats it.
EDIT: That is my V1 in my avatar which now resides in the roofspace it has served me well...the V2 is the plane I was referring to.
Cut off those tips, it doesn't get any simpler than that. My CG is at 165mm back has been since day 1.
I had the wingtips on for the first...30 flights. The I bought a Katana P and have not flown my Bad Boy since June 2006 until this past Sunday..after I cut the wingtips off (and I'm not one to leave planes at home for long)
The plane is a totally different machine now. It used to have wing rock like you would not beleive and never had that "locked in" feeling in any high alpha like my Katana does.
Without the wingtips it will harrier with very minimal wing rock (still not as little as my Kat) and the hovers have a much more controllable and locked in feeling. It will actually flatspin properly now too, almost push into a climbing flatspin.
Now I will actually have to make a concious thought about which plane to take to the field, have to stop instinctively grabbing the Kat
I wouldnt bother messing around with the CG and annoying computer mixes to try and fix it, set your CG a small amount aft of reccomended cut the tips off and thats it.
EDIT: That is my V1 in my avatar which now resides in the roofspace
it has served me well...the V2 is the plane I was referring to.
Your other option is to decrease wing size and thus increase wing loading, as this guy did.
04-28-2007 | 09:33 PM
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From: Brisbane, AUSTRALIA
RE: Wing rock problems.
ORIGINAL: JUGFLIER
Your other option is to decrease wing size and thus increase wing loading, as this guy did.
ORIGINAL: Fly-guy
Cut off those tips, it doesn't get any simpler than that. My CG is at 165mm back has been since day 1.
I had the wingtips on for the first...30 flights. The I bought a Katana P and have not flown my Bad Boy since June 2006 until this past Sunday..after I cut the wingtips off (and I'm not one to leave planes at home for long)
The plane is a totally different machine now. It used to have wing rock like you would not beleive and never had that "locked in" feeling in any high alpha like my Katana does.
Without the wingtips it will harrier with very minimal wing rock (still not as little as my Kat) and the hovers have a much more controllable and locked in feeling. It will actually flatspin properly now too, almost push into a climbing flatspin.
Now I will actually have to make a concious thought about which plane to take to the field, have to stop instinctively grabbing the Kat
I wouldnt bother messing around with the CG and annoying computer mixes to try and fix it, set your CG a small amount aft of reccomended cut the tips off and thats it.
EDIT: That is my V1 in my avatar which now resides in the roofspace it has served me well...the V2 is the plane I was referring to.
Cut off those tips, it doesn't get any simpler than that. My CG is at 165mm back has been since day 1.
I had the wingtips on for the first...30 flights. The I bought a Katana P and have not flown my Bad Boy since June 2006 until this past Sunday..after I cut the wingtips off (and I'm not one to leave planes at home for long)
The plane is a totally different machine now. It used to have wing rock like you would not beleive and never had that "locked in" feeling in any high alpha like my Katana does.
Without the wingtips it will harrier with very minimal wing rock (still not as little as my Kat) and the hovers have a much more controllable and locked in feeling. It will actually flatspin properly now too, almost push into a climbing flatspin.
Now I will actually have to make a concious thought about which plane to take to the field, have to stop instinctively grabbing the Kat
I wouldnt bother messing around with the CG and annoying computer mixes to try and fix it, set your CG a small amount aft of reccomended cut the tips off and thats it.
EDIT: That is my V1 in my avatar which now resides in the roofspace
it has served me well...the V2 is the plane I was referring to.
Your other option is to decrease wing size and thus increase wing loading, as this guy did.
Oh but I'm sure you're speaking from experience having owned a de-tipped Bad Boy and all?
04-29-2007 | 08:35 AM
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From: Muscle Shoals, AL
RE: Wing rock problems.
Seeing i went to school to be an engineer and the fact i have been building and flying planes since the midle 70s. What are your credentials? No i don't havea bad boy. I usually just draw my own plans and build my own plane. I am now working on one i call the Talisman, the fuse almost framed.
04-29-2007 | 04:50 PM
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From: Brisbane, AUSTRALIA
RE: Wing rock problems.
Ok, I don't have credentials as far as any certificates or education say so fair enough.
Yes you are right in saying I decreased wingspan and increased wingloading, thats just a given. However, the wingtips really are only a matter of 8-10sq in which on a wing like the Bad Boys is nothing at the end of the day.
All I know is that there is night and day between how the plane performed with the tips, and then without them.
I know alot of members on the Pro Bro forum that have done the same thing with the same results, as well as several other BB owners here in Aus who have done it as well.
Yes you are right in saying I decreased wingspan and increased wingloading, thats just a given. However, the wingtips really are only a matter of 8-10sq in which on a wing like the Bad Boys is nothing at the end of the day.
All I know is that there is night and day between how the plane performed with the tips, and then without them.
I know alot of members on the Pro Bro forum that have done the same thing with the same results, as well as several other BB owners here in Aus who have done it as well.
05-01-2007 | 01:23 AM
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From: Brisbane, AUSTRALIA
RE: Wing rock problems.
ORIGINAL: JUGFLIER
You know the saying about redneck idiots......... You can't tell them anything.
You know the saying about redneck idiots......... You can't tell them anything.
05-01-2007 | 08:29 AM
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From: Muscle Shoals, AL
RE: Wing rock problems.
ORIGINAL: Fly-guy
So redneck idiots and engineers come under the same classification [8D]
ORIGINAL: JUGFLIER
You know the saying about redneck idiots......... You can't tell them anything.
You know the saying about redneck idiots......... You can't tell them anything.
05-02-2007 | 07:18 PM
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From: Kershaw, SC
RE: Wing rock problems.
ummmm ... I thought the washout on a wing was to help stability. I like my Kat to death, but it still rocks durring a harrier .... unless it's inverted ... then it's smoothe as glass. Probably a CG thing ... or the ailerons might not be perfectly centered. I mix aileron and flap just to have the ailerons on separate channels. Comes in handy if you want to stop in mid air.
05-02-2007 | 10:57 PM
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From: Muscle Shoals, AL
RE: Wing rock problems.
It's possible that if you have washout you don't have a full symetrical wing. Therefore inverted you are not making as much lift as you do upright, hence your stability. In harriers and elevators, stall is king. You want the motor to provide lift as well as thrust, in many planes with lets say 4 strokes with bigger props, you get a little lift from the air forced over the airfoil at the center of the wing. On a tapered wing airplane this is the meat of the airfoil and this provides just enough lift to help stabilize the wing in a harrier. You just dont want to go too heavy on wing loading. But get a real thick airfoil and a light wingloading and sometimes these planes are not stable. Moving the cg back helps.
05-03-2007 | 05:15 AM
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From: Brisbane, AUSTRALIA
RE: Wing rock problems.
ORIGINAL: JUGFLIER
No the point is you guys are acting like trailer park redneck idiots.
ORIGINAL: Fly-guy
So redneck idiots and engineers come under the same classification [8D]
ORIGINAL: JUGFLIER
You know the saying about redneck idiots......... You can't tell them anything.
You know the saying about redneck idiots......... You can't tell them anything.
