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<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=984470916-23062003> Snap rolls that guys are doing today are making
it hard to even know whats right anymore. You get so used to looking at lousy
ones that you think a good one is bad. This is even a worse problem when
the people judging them fly in a lower class and they get used to looking
at bad snaps because of lack of experience. I'm of the opinion that a proper
snap has to roll, pitch, and yaw and leaves the original path if done
properly. You shouldn't be able to score a 10 on the manuever because it's not
possible. But hey that's just my opinion and untill someone shows me a better
way I'll continue my lousy snaps. Mike</SPAN></FONT></DIV>
<BLOCKQUOTE>
<DIV class=OutlookMessageHeader dir=ltr align=left><FONT face=Tahoma
size=2>-----Original Message-----<BR><B>From:</B> EHaury@aol.com
[mailto:EHaury@aol.com]<BR><B>Sent:</B> Monday, June 23, 2003 9:04
AM<BR><B>To:</B> discussion@nsrca.org<BR><B>Subject:</B> Snap rolls
(long)<BR><BR></FONT></DIV><FONT face=arial,helvetica><FONT lang=0 face=Arial
size=2 FAMILY="SANSSERIF">With the Nats fast approaching I thought it might be
useful to review / discuss the snap roll and its proper judging. My
observation is that there is a lack of quality demonstrated by many snaps.
There seems to be some tendency for folks that fly the maneuver poorly to
judge it leniently, or worse yet, judge well executed snaps harshly because
they look unfamiliar. No other maneuver is executed so quickly, making it even
more demanding to judge.<BR><BR>Please refer to page 78 of the rulebook under
"Snaps." Consider Item 1 carefully. <BR>"the nose should show a definite
break" and "while the track closely maintains the flight path" are key
criteria for judging the entrance to the snap. A rapid pitch attitude change,
simultaneously or closely followed by a yaw attitude change will create a
stalled wing in the direction of the snap and rapid autorotation rotation
generated by the opposite wing. The track will "closely" follow that
established before the snap.<BR><BR>I ask that you consider the often seen
snap entrance. The aircraft pitches, yaws, and rolls quite a bit off track
before the stall occurs. The aircraft then stalls and maintains that track,
finishing with considerable offset from the initial track. In my opinion, the
rules require the change in track during the snap iniation to be downgraded.
Typically the changes are 15 to 30 degrees in the vertical and horizontal
plane, so 1 or 2 points for each plane. At the same time, due to concurrent
application of aileron, some 15 to 30 degrees of roll occurs before the stall.
Another point or 2 off for lack of proper snap rotational angle <B>at the
entrance.</B> At the same time, please realize that there will be some small
change of track as enough attitude change occurs to initiate stall. This is
recognized in the rules i.e. "track <B>closely </B>follows." Certainly this is
another one of the approximation words that shouldn't be in rules. I believe,
however, that "closely" better defines 5 degrees or so of track change and
certainly does not allow 15 to 30.<BR><BR>Observe also that some pilots will
change the track horizontally (yaw) opposite the snap to accommodate the poor
entry and facilitate exit on the desired track. This change of entry track
should also be downgraded at 1 point / 15 degrees.<BR><BR>Item 2 describes a
barrel roll (zero). If the events described in the discussion of Item 1 occur
without an eventual stall, the maneuver is a barrel roll. It may be fairly
tight and still be a barrel. This is tough to call, I've video taped a number
of snaps that appeared fine but were clearly barrels when viewed in slo-mo.
The trick in judging this is to look for the CG to stay on the original track,
as stated in the rules. In my opinion, so many snaps are barrels that this
look may be becoming the standard, with true snaps on track are being judged
as axial rolls.<BR><BR>Item 3 deals with wing position at start and stop and
seems well understood.<BR><BR>Item 4 mentions that snaps may be either
positive or negative. Look for the proper horizontal break
direction.<BR><BR>Item 5 "If model returns to an unstalled condition" "such
that autorotation is not visible" "model rolls to complete" indicates that
rolling to finish a snap must be severely downgraded. I suggest that 1 point /
15 degrees is appropriate, as most of these rolled finishes will be 45 to 90
degrees which results in a 3 to 6 point downgrade. As per Item 1 there should
also be a severe downgrade for unstalling early. <BR><BR>Item 6 discusses
airspeed as not being a criteria.<BR><BR>OK, recognize that there is a lot
going on in a snap in very short period of time. Look for all the elements to
be there, clean break, with the nose and tail autorotating in an attitude
different from the track, and a unstalling and rotation stop at the proper
point. Please be aware that there are many details to be considered beyond "it
is or isn't" and "the wings finish in proper plane." Also recognize that well
performed clean snaps may look a bit different depending on technique and
aircraft. <BR><BR>These interpretations are my own and outside of any official
capacity. I welcome discussion, addition, and disagreement.<BR><BR>Good
flying<BR><BR>Earl</FONT> </FONT></BLOCKQUOTE></BODY></HTML>