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ACRO E-mail Archive Thread: Competition questions


Thread: Competition questions

Message: Re: Competition questions

Follow-Up To: ACRO Email list (for List Members only)

From: "Brian K. Howard" <BK at>

Date: Tue, 06 May 1997 14:07:41 UTC



To add just a bit to Patty's excellent comments--

1) Understand that a loop (or any looping maneuver) performed with a
crossbox wind does NOT have to be contained in a vertical (geometric)
plane. For example, a full loop performed on the X-axis with a Y-axis wind
will, in fact, be a corkscrew shape in the air. The judges should not
downgrade for any Y-axis drift during the figure. At your experience level,
unless the wind is hellacious, you would be better off (point-wise)
concentrating on flying the roundest loop you can and take whatever drift
happens. Unfortunately, the Sportsman Known doesn't have a wind corrector
figure until the very end, so, depending on the wind speed, you might need
to use the slight yaw or slipping technique Patty described to correct
*between* figures, if necessary. As you gain contest and flying experience
you will begin to integrate the "cheat" into the figures themselves.

2) Your third point on interpreting the rules is incorrect.

>        - Flight path over the ground not parallel to X-axis.

The judges *will* watch for the aircraft's longitudinal axis to remain
parallel to the X-axis, but the flight path (actually "ground track") may
angle depending on drift. Ground track is not a grading criteria. Ground
track only becomes truly critical when it takes you out of the box! Put
another way, given sufficient wind corrector figures, you could happily
move back and forth in the box on the Y-axis without penalty. Of course,
there are other "presentation" issues involved with Y-axis positioning, but
that complicates the discussions beyond your question.

Hope this helps some more.

Editor, HEADS UP!

At 08:07 AM 5/6/97 -0400, you wrote:
>I will be entering my first contest (Orange, MA) in a couple of weeks.  I've
>been reading the judging criteria in the Redbook, as well as reading from
>various other sources, and understand most of what the judges are looking
>for.  But I have a couple of questions regarding crosswind correction that I
>hope this group can help to clear up.
>I'm interested in (1) what the judges are supposed to look for, and (2) what
>they really look for.  I won't turn down any suggestions on how to cheat...
>Regarding looping maneuvers:  I understand you need wings level on
>entry/exit, and that the track over the ground must be a perfect circle, as
>of course all of mine are (yeah, right).  If there is a crosswind component,
>this implies some combination of roll/yaw.  The question is, will the judges
>downgrade if they see this, or are they just looking at the airplane's
>center of mass?
>Regarding horizontal lines (ie- a slow roll):  The way I read the rules,
>you're downgraded for any of the following:
>        - wings not level on entry/exit
>        - longitudinal axis not parallel to X-axis.
>        - Flight path over the ground not parallel to X-axis.
>In a crosswind, the first two necessarily conflict with the third, leaving
>your only option as cheating (OK with me), which in a strong wind and a weak
>Decathlon is only going to get you so far.  It's not possible to avoid some
>sort of a downgrade, and the real question is how to manage the flight to
>minimize the downgrades.  Am I interpreting this correctly?
>On an unrelated note- Anyone in the Boston area doing any critiquing this
>-Steve Pennypacker
Brian K Howard, CFI                voice: 937.434.7395
Editor, IAC Heads Up! Column       e-mail: BK at
FAI, National, & Teaching Judge
President, IAC Chapter 34
Extra 300/L, N343BH

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