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ACRO E-mail Archive Thread: [Acro] Fw: Re: Outside Snap

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ACRO E-mail Archive Thread: [Acro] Fw: Re: Outside Snap


Thread: [Acro] Fw: Re: Outside Snap

Message: [Acro] Fw: Re: Outside Snap

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From: "Chris Burns" <cjburns1 at>

Date: Tue, 05 Nov 2002 09:27:57 UTC


Re: [Acro] Outside SnapHi Ron
            What your doing using right rudder a negative snap (prop clockwise from the cockpit) and holding it in with full power is close enough to a Main Lomcovak.  Left forward stick at the same time and you would have it.  That sort of maneuver on a horizontal shortly to become a descending line is aircraft damage stuff.  Any Lomcovak type maneuver should be done on an ascending line so that the energy wash's off as it progress's.  The gyroscopic forces especially in a short wing high rotation aircraft can easily break a crankshaft and has in the past.  Couple that with a descending line gaining energy and how far do you want to go.  
If you to do those things find an instructor that knows how and get them to show you.
The actual snap you did with left rudder stopped early because you backed off the forward stick.  When you snap and unload a positive snap you have to load it slightly as you go inverted through the 3/4 position and then back it off again over the top if your doing multiples.
When you did a negative snap from inverted you bought the stick back at a point when you should be pushing forward again.  If you have an angle of incidence on your wings there is no need to unload inverted.  The inverted stall speed is higher and the "G" limits are lower so a good high speed stall has a small speed margin to occur.  
Full Left Rudder and forward right stick (95 to 100mph) and just do singles.  A Pitts has spiral instability inverted so it will be no trouble to stop online but most of all find an instructor to help you.

Chris Burns

----- Original Message -----
From: Dan 
To: acro at 
Sent: Sunday, November 03, 2002 3:38 AM
Subject: [Acro] Re: Outside Snap

I was hoping to see more posts on this topic.

What you describe sounds vaguely like a lomcevak, but I'm not the one to say for sure (having never done one).

Dan Pichelman <-- flying a Decathlon

  From: BONDR at
  Date: Tue, 29 Oct 2002 20:42:08 EST
  To: acro at
  Subject: [Acro] Outside Snap
  Resent-From: acro at
  Resent-Date: Wed, 30 Oct 2002 02:43:49 +0100

  OK, back to some acro  :-)

  I tried my first outside snap the other day (Pitts S-2B) and I think that I could use some help.  I started the snaps at about 100 mph from level inverted flight and my first one was a LEFT rudder snap.  I did accelerate the snap (just as I do the inside snaps) but the plane recovered at after 1/2 rotation.  All in all, not a bad way to terminate a new maneuver, but I was shooting for a full snap.  I tried a few more and they all ended up as 1/2 snaps.  So I figured "Lets try it with RIGHT rudder."  Well, it snapped nicely (like I expected the left rudder to snap) and I watched the world go around about one and a half times then "All Heck Broke Loose."  I'm not sure exactly what happened, but further experimentation proved that it was repeatable!

  So the question is "What's going on and what am I doing wrong?"

  Thanks in advance,

  Rob Bond 

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