calcifer Posted August 29, 2016 Share Posted August 29, 2016 (edited) Hello to everybody. Last saturday I performed my first medium-range flight (abt. 30 km.) and I noticed how I had to frequently intervene with right brake light tractions in order to keep a straight route, since the wing had the constant tendence to lightly turn left. I have to exclude the wind, since it happened both on the gone and return route, with opposite wind directions. The harness is correctly tuned, the trims were setted in the same exact specular position (1/3 open). My engine is a vittorazi fly 100 (clockwise propeller ). Could it depend from only the torque effect (even in levelled flight a@ costant RPM ) ??? Edited August 29, 2016 by calcifer Quote Link to comment Share on other sites More sharing options...
morgy Posted August 29, 2016 Share Posted August 29, 2016 Could be chassis geometry.. what machine are you using? you can slightly offset the hang points when you have exhausted all other options.. Quote Link to comment Share on other sites More sharing options...
calcifer Posted August 29, 2016 Author Share Posted August 29, 2016 my frame is a fly products "race c" with high hang points standard apco harness exactely as the pictured one http://www.flyproducts.com/ita/paramotori/paramotor-standard/race-c/ Quote Link to comment Share on other sites More sharing options...
morgy Posted August 30, 2016 Share Posted August 30, 2016 does it turn the opposite direction when engine off? Quote Link to comment Share on other sites More sharing options...
calcifer Posted August 30, 2016 Author Share Posted August 30, 2016 3 minutes ago, morgy said: does it turn the opposite direction when engine off? well, I really cannot tell it. I do turn off the engine only in the final phase of the landing, and in that occasion I'm so concentrated in the landing that I don't care. If you mean when the engine is idling (my engine has the clutch) I would say that it goes straight. Quote Link to comment Share on other sites More sharing options...
ptwizz Posted August 30, 2016 Share Posted August 30, 2016 There are many reasons why you might have a slight turn to one side: Are your trimmers set to exactly the same position? Do you keep equal pressure with both feet on the speedbar? Are you perfectly central and symmetrical in your harness? Do you have a side mounted reserve? Do you have asymmetric weight (e.g. all your right side pockets full of keys, change, spanners etc? Even with the high hang points of the Bailey 175, I can offset any yaw tendency either with the trimmers or asymmetric pressure on the speedbar. 1 Quote Link to comment Share on other sites More sharing options...
calcifer Posted August 30, 2016 Author Share Posted August 30, 2016 (edited) 1 hour ago, ptwizz said: There are many reasons why you might have a slight turn to one side: Are your trimmers set to exactly the same position? yes, I've double checked during the flight, the trimmers are perfectly symmetrical Do you keep equal pressure with both feet on the speedbar? don't have any speedbar installed Are you perfectly central and symmetrical in your harness? Yes. I am Do you have a side mounted reserve? No, I don't have any reserve installed Do you have asymmetric weight (e.g. all your right side pockets full of keys, change, spanners etc? No, only smartphone in my right pocket Even with the high hang points of the Bailey 175, I can offset any yaw tendency either with the trimmers or asymmetric pressure on the speedbar. see my answers above. So you think I could contrast the tendency of going left by closing just a little bit more the right trim ? or better to open a little bit the left ? As written, i do takeoff and fly in nill wind with 1/3 of trimmers opened Edited August 30, 2016 by calcifer Quote Link to comment Share on other sites More sharing options...
morgy Posted August 30, 2016 Share Posted August 30, 2016 7 hours ago, calcifer said: see my answers above. So you think I could contrast the tendency of going left by closing just a little bit more the right trim ? or better to open a little bit the left ? As written, i do takeoff and fly in nill wind with 1/3 of trimmers opened If your turning and you have to add weight or offset trims to make you fly straight that's a Poorly designed machine!!! Quote Link to comment Share on other sites More sharing options...
easttowestyorkshireparamot Posted August 30, 2016 Share Posted August 30, 2016 So first thing is first. When your flying. There is no wind. You are part of it. Think of your self as a little bubble floating around. Yes your ground speed changes. But you are now the wind so to answer your earlier question. Wind has no influence. Every machine has torque stear. Don't let any one kid you on that. Direct drive stears you right. Direct clutch stears you left. Belt drive clutch stears you right. If you fly a dudek Wing they come with a torque line. This you set with a knot... several in fact depending on the power you have applied. If you don't have a torque line the only other way is to set your trim slightly faster on the on torque side. However... Unless you stay even on the power the hole flight it's pointless. You'll spend all your time playing with trims instead of enjoying the view. Hope that helps. Paul East to West Yorkshire paramotor club Bull dog paramotors dudek wings 1 Quote Link to comment Share on other sites More sharing options...
calcifer Posted August 31, 2016 Author Share Posted August 31, 2016 My engine is a direct clutch, so , yes it slightly steers left according to your description. thanks. Quote Link to comment Share on other sites More sharing options...
morgy Posted August 31, 2016 Share Posted August 31, 2016 I fly hands off with my 16m full trims and bar with no turning, I can also fly at slower trim on the 16m. 18m Viper 4 is the same and on my old Viper 3 22m straight with no turning, It's all down to the geometry of your machine. Quote Link to comment Share on other sites More sharing options...
asquaddie Posted August 31, 2016 Share Posted August 31, 2016 On Dudek wings is there two position loops you can lock your carabiner in? This enables you to off set it enough on either side. Quote Link to comment Share on other sites More sharing options...
calcifer Posted August 31, 2016 Author Share Posted August 31, 2016 16 minutes ago, asquaddie said: On Dudek wings is there two position loops you can lock your carabiner in? This enables you to off set it enough on either side. my ITV dolpo wing has 2 hook points, one abt. 1/2 inch over the other. So you say that hooking the right carbine on the upper hang point could solve the problem of the left turning ?? Quote Link to comment Share on other sites More sharing options...
ptwizz Posted August 31, 2016 Share Posted August 31, 2016 My Ozone Indy has 2 loops. As I understand, these are for use with high an low hang points. I have high hang points, so I use the upper loops. I'm not sure how a paramotor and wing can be statically trimmed to fly straight at all power settings. All torque applied to the prop must be reacted through the risers and lines. Changing the balance of loads across the risers causes a turn (all other factors remaining equal). This is the same whether the load change comes from torque or weight shift. Quote Link to comment Share on other sites More sharing options...
asquaddie Posted August 31, 2016 Share Posted August 31, 2016 41 minutes ago, calcifer said: my ITV dolpo wing has 2 hook points, one abt. 1/2 inch over the other. So you say that hooking the right carbine on the upper hang point could solve the problem of the left turning ?? My two Dudek loops are only a few mm apart and I do use the upper left one and the lower right one. And it does help the torque a lot. Can any one else confirm this is correct - I'm no expert on the wing sorry?? Quote Link to comment Share on other sites More sharing options...
Hann__ Posted August 31, 2016 Share Posted August 31, 2016 My old Synth used to do this and it was very noticeable - even on the first flight with it, it used to turn right so much that when looking at my GPS logs after a flight a `straight` track was a continuous series of arcs to the right with corrections to the left couteract them. The only time it flew straight was down-wind. It was bloody annoying and got to be something of a preoccupation while flying. The TEA line didn`t really help much. Didn`t try the different hook-in points as slight trimmer adjustments would have the same effect which is something i tried as well. Since changing my wing one of the very first things i noticed was it flew dead straight which is much more condusive to a satisfying flight! Quote Link to comment Share on other sites More sharing options...
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