[SPAM] Re: Judging Snaps

[David Flynt]

Troy,

Thank you.  Great info.

David

  ----- Original Message ----- 
  From: Troy A. Newman 
  To: discussion at nsrca.org 
  Sent: Thursday, August 04, 2005 9:26 PM
  Subject: [SPAM] Re: Judging Snaps


  Hey David,

  If the model gives the cone you describe...then it broke in pitch!  If the model doesn't show the cone then it didn't break in pitch. Just a note that if it cones it also departed the path in yaw as well. 

  I agree with you 1000000000% if its not a barrel, and its not a axial roll this its a snap...we all know what the barrel looks like...and we all know what the axial roll looks like...The snap is the only other rotation thing the model can do in the roll axis.

  This is pretty easy to see if you think about it this way...The only way it can show the CONE is if it had a BREAK or departure (a break in pitch). If it never broke then it will not show the cone!

  Speed of rotation is very very dependant on lots of factors. More rudder will cause the snap to be more violent and as a result it can rotate very fast. More aileron will cause the snap to be tighter and still have a higher rotation rate. More elevator will cause the model to start the cone quicker. Not enough elevator and the typical scene is the model stalls but only after about a 1/8-1/4 rotation. This can be seen in the snap that winds up...where it rotates slowly then gets lightning fast when the wing finally departs. This is usually a very unpredictable exit with the pilot missing most of them.

  Another note is a snap that describes a cone and stays online is actually a more pure break or a better break...but sometimes the snap police or SNAP Nazi will zero this snap. The reason is the model stalls quicker and pitches first meaning the model doesn't jump left or right....The ones that jump over are not quite stalled when the rudder and or aileron is applied. If it stalls quickly like the rule book sometimes it harder to see the stall...or the pitch but you can see its effects in the CONE for sure. The only way it can cone is if it broke....No cone no break!

  Another note to the pilot flying it. The snaps are easiest to do at the slowest possible speed. Reason it takes less pitch or elevator to get the wing to stall right away. This makes them stay on heading better...The bench mark is do you have enough energy after the snap to keep flying or is the model wallowing and falling out of the sky...or is it coming in fast and the rotations are quick and the snaps are extremely violent...then you might have too much speed or energy.

  Troy Newman




    ----- Original Message ----- 
    From: David Flynt 
    To: discussion at nsrca.org 
    Sent: Thursday, August 04, 2005 9:04 PM
    Subject: Judging Snaps


    I have always judged snaps with a simple rule -- if it is not a barrel role, and if the tail describes a helix or cone, then the plane must be stalled, and therefore it is a snap.  I have never downgraded because the plane is set up with a lot of aileron, so long as the tail wags, and so long as the nose and tail describe opposing helixes.  I don't see any reference to how fast or slow the plane rolls with regard to downgrades.  To me, a pilot is free (and smart) to set up their plane such that it loses as little heading as possible in a snap.  

    Am I completely mistaken on this?  A barrel roll is easy to detect.  An axial roll is easy to detect.  If it is not a barrel roll, and not an axial roll, then it must be a valid snap, even if it is subtle and the plane is not buried deeply in a snap.  At least that is my current understanding.

    I'll admit that I don't really understand the degree at which the plane must "break" in the direction of  snap.  Who came up with that idea?  What really does that mean, and how do you measure it?  "the nose of the fuselage should show a definite break in the direction of the snap".  Ok, what is definite?  At what point exactly must the aircraft become stalled?  It takes time for the control surfaces to deflect.  It does not happen instantaneously.  

    I think the maneuver is over described and over analyzed.  Its a "rapid autorotation in the pitch, yaw, and roll axes of flight in a stalled wing attitude."  That should be good enough to judge it.  If not, maybe use my definition of judging it.  Until I know what a "definite break" is, that's what I am going to do.

    David  
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