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ACRO E-mail Archive Thread: 1/2 Snap

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ACRO E-mail Archive Thread: 1/2 Snap


Thread: 1/2 Snap

Message: RE: 1/2 Snap

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

From: glepore at (Guido Lepore)

Date: Mon, 01 Apr 1996 17:46:35 UTC


  > The 1996 Advanced Known has an upright half-snap roll on a 45 degree up line.
> Any good advice on how to execute this in a Pitts S1?
> I just got my plane flying again. Its been down 6 months.
> I have never been trained in 1/2 snaps. I am tending to over rotate the
> snap.  I probably just need to practice more.  I think I recall
> the 'Fly for Fun to Win' book stating that these need to be done as
> a 1/4 snap followed by a 1/4 outside snap to make a good looking 1/2 snap.
>Herman Dierks, Dept. E54S, AWSD, Austin, Texas
>mail:  dierks at

You can try snapping left, this may go a little slower and you may be more
familiar with the visual clues from the more frequently flown left roll.

The more common problem is coming off heading, since you initially yaw one
way with rudder, and then aggravate that yaw when you step on the opposite
rudder (but inverted, therefore same yaw direction) to stop the snap.

Use the  minimum rudder and elevator to get the snap started.  Almost
before the rotation starts, come forward on the stick.  Its hard to explain
how much, you have to experiment.  If you leave the stick back, the yaw
will be aggravated as you go through knife-edge.  By the same token, if you
bring the stick quite a way forward you'll help to push the nose back on
heading as you go through knife-edge.  Stop the snap with a little one-two
tap of the opposite rudder followed by the same rudder (as you initiated
the snap with).  This should minimize the apparent yaw to the judges.

If you're still a little off, bluff it and don't try to get back on line.
If you're a ways off, then correct a little, so the judges think "oh, he's
correcting 5 degrees, that must have been his error".

For best points, concentrate on nailing that 45 line after the snap.  Just
like a job interview,  the last impression is the one the judge remembers.

Guido Lepore
glepore at     .   .  .  . .._ _////


© Dr. Günther Eichhorn
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