A
1 file version, leave this alone

  0 -Re number|-(million) { Reynolds number basically is equal to the CHORD (size) of the wing times the SPEED of the airplane times a constant. Light planes may have a Reynolds number of about 9 million.
  1 -Thickness|-(ratio) { Thickness ratio is the ratio of how THICK the airfoil is at it's thickest point to it's CHORD (from leading edge to trailing edge). Typical thickness ratios go from about 0.08 (for a thin, low-drag airfoil) to 0.16 (for a thick, hi-lift airfoil).
  2 -Drag Div Mach|-(at zero lift) { This is the Mach number at which compressibility effects become apparent AT ZERO LIFT. 0.75 is a good default. Supercritical foils should enter a higher number, like perhaps 0.85 or even 0.90. Remember this is the Drag Divergence Mach number at ZERO LIFT. X-Plane will reduce this number as lift is produced!
  3 intercept { The lift intercept is the amount of lift the foil puts out at zero degrees angle of attack. This is the lift when the wing is aimed straight into the wind, and is not pitched up at all. 0.20 is a typical value.
  4 slope { The lift slope is the amount of lift the airfoil puts out for each degree angle of attack the wing has on the air. Airfoils almost always have a lift slope of very close to 0.1.
  5 lin range { This is the range of angle of attack (from 0 in either direction) that provides a linear increase in lift.
  6 power { Tune this number so the lift curve transitions smoothly into the stall.
  7 maximum { This is the maximum coefficient of lift that the airfoil can put out. 1.6 is common.
  8 drop { This is an indication of how sharp the stall is... a foil with a sharper stall will lose lift more abruptly when the wing goes to too high an angle of attack. A larger number here will result in a more sudden stall with a sharper drop of the airplane in flight.
  9 power { Tune this number so the lift curve transitions smoothly after the stall.
 10 drop { This is an indication of how much lift is lost after the stall... thick and supercritical airfoils lose little lift, but thin low-drag airfoils lose a lot of lift here.
 11 d-min { This is the minimum parasite drag coefficient of the airfoil. It probably occurs at an angle of attack close to zero degrees.
 12 min-d cl { This is the coefficient of lift at which the minimum drag coefficient is achieved. It is probably close to the lift intercept value you entered above.
 13 d alpha=10 { This is the parasite drag coefficient of the airfoil at an angle of attack of 10 degrees.
 14 power { This number is theoretically close to 2.0, but you can tune it to fit actual data.
 15 cl location { Some airfoils have a certain angle of attack range where the airflow is laminar, resulting in very low drag. This is the lift coefficient of the laminar flow low-drag bucket, if any.
 16 width { This is how wide the low-drag laminar flow bucket is, in terms of lift coefficient. It is the lift coefficient range across which dragis reduced by laminar flow.
 17 depth { This is how much the coefficient of drag is reduced by laminar flow (if any).
 18 power { This is the power of curvature of the low-drag laminar flow bucket... 2.0 might be good guess.
 19 alpha 1 { This is the angle of attack at which the airfoil pitching-moment changes... it is almost always the same as the stalling angle of attack, entered below.
 20 alpha 2 { This is the angle of attack at which the airfoil pitching-moment changes... it is almost always the same as the stalling angle of attack, entered below.
 21 cm 1 { This is the coefficient of pitching moment at -20 degrees angle of attack. The pitch moment is an indication of how much the airfoil tends to twist UP. Since airfoils almost always pitch DOWN, this number is almost always negative.
 22 cm 2 { This is the coefficient of pitching moment at the pitch-moment change entered above. The pitch moment is an indication of how much the airfoil tends to twist UP. Since airfoils almost always pitch DOWN, this number is almost always negative.
 23 cm 3 { This is the coefficient of pitching moment at the pitch-moment change entered above. The pitch moment is an indication of how much the airfoil tends to twist UP. Since airfoils almost always pitch DOWN, this number is almost always negative.
 24 cm 4 { This is the coefficient of pitching moment at  20 degrees angle of attack. The pitch moment is an indication of how much the airfoil tends to twist UP. Since airfoils almost always pitch DOWN, this number is almost always negative.
 25 alpha min { This is the negative angle of attack at which the airfoil stalls. The stall is the point at which the airfoil cannot put out any more lift and (usually abrubtly) throws in the towel and loses lift.
 26 alpha max { This is the positive angle of attack at which the airfoil stalls. The stall is the point at which the airfoil cannot put out any more lift and (usually abrubtly) throws in the towel and loses lift.

600 BE ADVISED
601 SAY INTENTIONS
602 Understood
603 Enter Name
604 Enter ID
605 Go Up a Level
606 Cancel
607 Save
608 Don't Save
609 Cancel
610 Save changes to 
611 first?
612 Version and Updates
613 Open / Save

-1