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Line Rake Analysis

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Weight of model in ounces: or in grams:

Wing span of model in inches:
    Inboard:   
   Outboard:

Line diameter in inches:

Number of control lines:

Line length (handle to a/c centerline) in feet:

Wing area in sq. in.:

Lap time in seconds:

Calculations done as follows
(Corrections and improvements solicited!) 

	/* InbSpan = Inboard wing span in feet
	   OutbSpan = Outboard wing span in feet
		 Span = InbSpan + OutbSpan */
  Rho = .002378
  Gravity = 32.17
  Mu = .000157
  E = .85
  CdPe = .01 /*Coefficient of Parasitic Drag */

  Velocity = Radius * TwoPI / LapTime  /* Velocity in ft/sec */

  Gamma = atan ( .686 * Rho * Gravity / Weight * N * Radius * Radius * Diam *
         ((Velocity*Diam/Mu)**-.232)* ( (1.0 - InbSpan/Radius)**2.768) ) * 57.3

  LineSweep = InbSpan * 12 * sin(Gamma/57.3)

  ---------------------------------------------------------------------

  WingArea = WingArea / 144.0  /* Get wing area in sq. ft. */

  AspectRatio = ( Span**2 ) / WingArea;

  CdL = 1.868 *  (Velocity * Diam / Mu)**-.232 ) *
                 (1.0 - InbSpan  / Radius)**2.768

  Drag = .5 * Rho * (Velocity**2) * WingArea * ( CdPe + ( Weight*Weight /
          ( ((.5*Rho)**2)*(Velocity**4)*(WingArea**2)*PI*AspectRatio*E)) +
        .735 * N * Radius * Diam * CdL / WingArea )
 
  LineDrag = .5 * Rho * Velocity*Velocity * .735 * N * Radius * Diam * CdL;   

  ACDrag = Drag - LineDrag

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