"Line Whip"

[Jim Pollock]

Hi All,

What are the best ways to limit line whip and how much whip is too much?

Jim Pollock   

[Clint Ormosen]

Not really sure what you mean here, Jim. To me, whipping the lines is like dragging the model around the circle, leading it faster.
Sorta kinda.
Could you explain a little?

[Bill Little]

Let's see...... I would say five guys on each side, maybe six, would be the limit to the whipping line.  More than that and it gets too painful!

Of course it all depends on the size of the paddles allowed, and how fast you can run..................

[Jim Pollock]

I meant line whip during manuvering..... Whatsamatter, can't y'all read my mind?

Jim Pollock   

[Clint Ormosen]

Are you getting a loss of line tension through the maneuvers?

[Richard Oliver]

Jim, Line whip first and foremost comes from the lines being too long or lead outs too far back or both. Try moving them forward first and maybe a little extra tip weight if you need more line tension. The worst byproduct of lines too far back is it makes it very hard to start and stop a corner smoothly. The other item is it causes your plane to yaw excessively in hard maneuvers exacerbating the line whip.
RO

[Bill Little]

Thanks, Richard for an answer, and thanks Jim for the question (now that I know what it was.....).  I have never experienced "line whip", AFAIK...........

I would like to *see* it sometime so that I know what it looks like.

Bill <><

[phil c]

Take your Fox 35 powered Nobler out.  Richen the setting to get about5.5 sec laps on 60 ft. lines. 
Try some consective square eights, with the corners as sharp as you can make them.  By about the fifth or sixth corner the plane will have slowed down and the lines will be whipping it around on every corner.  Watch out it doesn't get away from you on the sixth and seventh corners- high, outside turns with no Rabe rudder.

[Bill Little]

Take your Fox 35 powered Nobler out.  Richen the setting to get about5.5 sec laps on 60 ft. lines. 
Try some consective square eights, with the corners as sharp as you can make them.  By about the fifth or sixth corner the plane will have slowed down and the lines will be whipping it around on every corner.  Watch out it doesn't get away from you on the sixth and seventh corners- high, outside turns with no Rabe rudder.

Thanks, Phil, but I'll pass!

Bill <><

[Marvin Denny]

I meant line whip during manuvering..... Whatsamatter, can't y'all read my mind?

Jim Pollock   

  How much is too much??  ANY is too much!! 

  Problem--  Anytime a CL model changes direction either suddently or even moderately , line whip occurs to some extent.
  Fact--  It can (and must) be reduced by a variety of methods.
  Less line weight and size (dia).  Since we already are limited in minimum dia   that is out.  Shorten the lines   -- Not practical as lap times go up.
  So generally line adjustments are out
  Plane adjustments---  Increase pull by some means . Weight increase is usually not desireable  likewise so is engine offset and/or rudder offset  those alterations cause other problems more detrimental to good flight than  line whip.  That leaves  line sweep adjustment, tip weight, and CG.
  Those you can usually adjust in small increments and test flying to get the minimun "EFFECT" of line whip and still get decent other flight characteristics.  The harder one hits the corners or  tightens up ANY turn will acerbate the line whip effect.

  It is the old "A body in motion will tend to remain in motion in a given direction until acted upon by an outside force" Quote.   The lines (having weight),  tend to go on straight a short time and distance AFTER the plane starts to turn.   The more bow back in the lines from the plane to pilot, the more "whip" is encountered at any given speed  and pull.

  Bigiron

[Bill Little]

Do you breath *IN* or *OUT* on your backswing?

[Dick Fowler]

Do you breath *IN* or *OUT* on your backswing?

Hey Bill, I breath in... that way I have enough air to yell expletives after! 

[Bill Little]

Hey Bill, I breath in... that way I have enough air to yell expletives after! 

   

To be honest, Dick, it almost sounded like that question some people ask on the first tee as the other guy is going through his preshot routine.  Get's them thinking about it enough (sometimes) that they can't hit the ball worth a darn.

I have never experienced line whip, so I didn't know it happened to the extent that it must for some people.

AS to my golf swing, I learned 30 odd years ago, playing with the other sectional pros, to ignore any and all things said on the course!

Bill <><

[phil c]

Some additions to what Bigiron said-
You have to minimize the line rake.  With fixed AMA line sizes, the only way to do that is to increase the airplane weight.  That is a good part of the reason a Nobler tends to fly better at 45 oz. than much lighter.  A 45 oz. plane plane on 60 ft lines pulls about 9.5 lbs. at 55 mph which results in needing very little line rake, about .6 in. according to the calculators.  That speed and pull makes the lines pretty straight and they don't whip, as long as the speed keeps up.  If you can build a 38 oz. Nobler with a 25 and fly it on 60 ft 012 lines, that should work pretty well too.

Just from observation,  018 lines need more pull, 11 lbs. or so, from a 62 oz. plane going 55 mph on 63 ft. lines.  That combo works very well too.

Be careful in the sharp manuevers.  It takes a lot of practice to hit the corner smooth and fast(on the controls) so the plane doesn't slow down too much.  Snapping full up can stall the flaps and really slow the plane down quickly, and make the lines start to whip around.