[NSRCA-discussion] Snap entry in FAI
vicenterc at comcast.net
vicenterc at comcast.net
Tue Jun 17 14:24:26 AKDT 2008
Two paragraphs below the one that Dave mention states:
"At the start of the snap-roll, the fuselage attitude must show a definitive break and separation from the flight path, before the rotation is started, since the model the model aircraft is supposed to be in a stalled condition throughout the manuever"
--
Vicente "Vince" Bortone
-------------- Original message --------------
From: "Dave" <DaveL322 at comcast.net>
> Ok.....
>
> What it does say is:
> "in a stalled attitude, with a continuous high angle of attack"
> "a stalled condition throughout the manoeuvre"
>
> So any rotation prior to the high angle of attack would be downgraded 1
> point per 15 degrees, and if the high angle of attack is never visible, then
> the downgrade should be more than 5 points.
>
> I'd say losing 6 points on the snap element of a maneuver would be pretty
> good incentive to use the elevator in snaps.
>
> Regards,
>
> Dave Lockhart
>
>
>
>
>
> -----Original Message-----
> From: nsrca-discussion-bounces at lists.nsrca.org
> [mailto:nsrca-discussion-bounces at lists.nsrca.org] On Behalf Of
> rcmaster199 at aol.com
> Sent: Tuesday, June 17, 2008 1:49 PM
> To: nsrca-discussion at lists.nsrca.org
> Subject: Re: [NSRCA-discussion] Snap entry in FAI
>
> Yes I read it again and still don't see where it is stated that the
> departure in attitude is in pitch axis. Attitude change can be in any
> of the three main axes IF you take the reg literally. Troy Newman made
> this argument to me a year ago and he was / is correct. However, as I
> argued to Troy, departure in pitch causes things to happen correctly in
> a snap / flick roll. I will not restate what I wrote earlier but it
> still holds true
>
> MattK
>
>
> -----Original Message-----
> From:
> nsrca-discussion-bounces at lists.nsrca.org
> [mailto:nsrca-discussion-bounces at lists.nsrca.org]On Behalf Of Jon
> Lowe
> Sent: Monday, June 16, 2008 12:11 PM
> To:
> nsrca-discussion at lists.nsrca.org
> Subject: Re: [NSRCA-discussion]
> Snap entry in FAI
>
> I suggest people re-read the definition
> ofsnap-rolls from the FAI sporting code. I did a few minutes
> ago. Here it is:
>
>
> "5B.7.5. SNAP-ROLLS
> A snap-roll (or flick roll/rudder roll) is a rapid
> autorotative roll where the model aircraft is in a stalled
> attitude, with a continuous high angle of attack
> Snap-rolls have the same judging criteria as axial rolls as
> far as start and stop of the rotation, and
> constant flight path through the manoeuvre is concerned.
> At the start of a snap-roll, the fuselage attitude must show a
> definite break and separation from the
> flight path, before the rotation is started, since the model
> aircraft is supposed to be in a stalled
> condition throughout the manoeuvre, If the stall/break does
> not occur and the model aircraft barrelrolls
> around, the manoeuvre must be severely downgraded (more than 5
> points). Similarly, axial
> rolls disguised as snap-rolls must be severely downgraded
> (more than 5 points).
> Snap-rolls can be flown both positive and negative, and the
> same criteria apply. The attitude
> (positive or negative) is at the competitor’s discretion. If
> the model aircraft returns to an unstalled
> condition during the snap-roll, the manoeuvre is severely
> downgraded using the 1 point/15 degree
> rule."
>
> Note that "the fuselage attitude
> must show a definite break and separation from the flight path,
> before the
> rotation is started..." That means that simultaneous pitch and
> rotation is specifically NOT permitted. I would interpret it as
> meaning
> that pitch and yaw could theoretically happen simultaneously, as long
> as no
> roll is involved. Sorry Matt, the rules as written do NOT allow
> actuation in all three axes simultaneously. The rule also states
> that a
> constant flight path has to be maintained.
>
> Let's face it, the only way
> to prevent severe downgrading from EVERY judge, not just some judges,
> is to
> have a pitch break first. Takes any question away.
>
>
> Jon Lowe
>
> -----Original
> Message-----
> From: rcmaster199 at aol.com
> To:
> nsrca-discussion at lists.nsrca.org
> Sent: Mon, 16 Jun 2008 10:46
> am
> Subject: Re: [NSRCA-discussion] Snap entry in FAI
>
>
> A
> "Flick" and a "Snap" roll are the same roll in full scale aerobatics
> parlance
> and reference material.
>
> Do these mean the same thing in
> model aerobatics? In my view, they do
>
> The latest FAI regs
> allow actuation of the three main axes simultaneously...that is, the
> regs
> don't specifically differentiate "Pitch Break" from other deviations.
> I don't
> think they specifically require that the model must rotate about it's
> flight
> path either, I don't believe (.....plane must rotate in a conical
> fashion
> about the fight axis....). The model would probably present the best
> if that's
> done, so pilots may want to consider that when executing the
> maneuver.
>
> In my take, a rapid Pitch is desired to preload
> the wing. Contrary to popular belief, both panels dot not have to
> stall for a
> snap to occur. Quite the opposite. Upon rudder deflection, the port
> panel will
> practically stall (lift much much less than the other panel) but the
> starboard
> panel must be lifting to create the autorotation. If both panels
> stall, the
> model will fall out of the sky for a distance and a snap would not
> occur at
> the correct moment in
> time
>
> MattK
>
> -----Original
> Message-----
> From: Woodward, Jim (US SSA) <jim.woodward at baesystems.com>
> To:
> General pattern discussion <nsrca-discussion at lists.nsrca.org>
> Sent:
> Mon, 16 Jun 2008 8:47 am
> Subject: Re: [NSRCA-discussion] Snap entry
> in FAI
>
> Guys,
>
> I thought the FAI changes
> explicitly allowed flick rolls? The rule
> reads, "... fuselage
> attitude must show a definite break and separation
> from the flight
> path."
>
> It does not say, "MUST SHOW PITCH BREAK." Please DO
> NOT ERROUNIOUSLY
> APPLY A PASS/FAIL MAJOR DEDUCTION initial assessment
> to the snap roll.
> Watch the whole maneuver then render your
> score.
>
> A break and separation from the flight path simply
> means that the nose
> and tail of the plane must rotate in a conical
> fashion about the fight
> axis. Yaw, roll, and pitch can all break at
> the same moment if that is
> how the pilot does
> it.
>
> Hey :) some really handsome smart guy wrote some stuff
> at this link
> below about snap rolls to help clarify how they are done
> in IMAC.
>
> http://www.mini-iac.com/DesktopDefault.aspx?tabid=77
>
> thanks,
> Jim
>
>
> _______________________________________________
> NSRCA-discussion
> mailing list
> NSRCA-discussion at lists.nsrca.org
> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion
>
>
>
> Get the Moviefone Toolbar. Showtimes, theaters, movie news,
> & more! _______________________________________________
> NSRCA-discussion mailing list
> NSRCA-discussion at lists.nsrca.org
> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion
>
>
> _______________________________________________
> NSRCA-discussion mailing list
> NSRCA-discussion at lists.nsrca.org
> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion
>
> _______________________________________________
> NSRCA-discussion mailing list
> NSRCA-discussion at lists.nsrca.org
> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.nsrca.org/pipermail/nsrca-discussion/attachments/20080617/4ad85e67/attachment.html>
More information about the NSRCA-discussion
mailing list