Track v.s. Heading

[Don Ramsey]

Bill,

Thanks,
Don
  ----- Original Message ----- 
  From: Bill Glaze 
  To: discussion at nsrca.org 
  Sent: Monday, June 06, 2005 8:21 PM
  Subject: Re: Track v.s. Heading


  Don:
  Very lucid explanation.  Anything I can do to help try to correct it, I'll do.  Just let me know.  Bill Glaze

  Don Ramsey wrote:

    OK, here's my thoughts on heading and track.  They are very different terms.  Track is the path of the model over the ground.  Heading is the direction the nose is pointed.  With no wind, heading and track are the same.  The downgrades for some turnaround maneuvers are absolutely incorrect when there is the statement, "Model heading does not finish exactly opposite direction of entry."  

    Let's take an example:
    Say the course parallel to the flight line is north-south (360 or 180 degrees).  Assume the 180 degree heading is from left to right.  With no wind, if the model is flying parallel to the flight line the heading and track will be 180 degrees from left to right. Now assume an in blowing wind that requires a 15 degree correction to maintain a path parallel to the flightline.  Remember the track of the model must be wind corrected to track parallel to the judges.  The heading is now 165 degrees but the track is 180 degrees.  The model is crabbed into the wind 15 degrees with the wings level as required by our regs and the nose is pointed away from the pilot.  Now assume you do a half loop as a turnaround.  The opposite heading to 165 degrees is 345 degrees.  And that heading points the model into the flightline not away as would be required for wind correction.  How many judges would award a perfect score if the model was pointed into the flightline when an opposite correction was required?  These mis-stated downgrades in the regulations have been ignored for years (at least I hope they have).  Substitute track for heading and the model is now required to exit the half loop on an exact opposite track.  In other words, parallel to the flightline entering the maneuver and parallel to the flightline on exit.

    Don

    PS: On all modern jetliners the NAV display has pointers for both heading and track and they are seldom the same in the air.
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