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ACRO E-mail Archive Thread: [Acro] Fw: Fw: Vertical Reversements or Cartwheels

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ACRO E-mail Archive Thread: [Acro] Fw: Fw: Vertical Reversements or Cartwheels


Thread: [Acro] Fw: Fw: Vertical Reversements or Cartwheels

Message: [Acro] Fw: Fw: Vertical Reversements or Cartwheels

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From: "Chris Burns" <cjburns1 at>

Date: Sun, 29 Sep 2002 02:07:02 UTC


Hi Virginia
                Yes the aircraft actually turns and does a 180deg and comes back the other way as in a stall turn.  What happens is when you are on a 45deg up line and do a snap roll at low speed you will increase that line to say 60deg.  If the aircraft rotated (Roll) 180deg you finish with the nose down and possibly 30deg inverted.  However if you go to the left (with a clockwise prop rotation from the cockpit) the yaw to the left because this is a snap roll and not a slow roll the gyroscopic effect of the prop pitch,s the nose up when it rotates it will bring the acft nose forward so you finish with a positive angle to the ground.  The main thing is to do the snap with very low airspeed.  These things actually work better in low powered aircraft like Cessna 150s and the like.  The aircraft rotates in 3 dimensions similar to what happens in a Lomchovack but there is not the great twisting forces on the fuselage.
With descriptions of these type of compound maneuvers (a Snap roll plus gyroscopic effects, a 45deg up line and a 180deg reversement to use a popular term.) it is a bit harder to visualise.  To understand it properly you need to understand these individual components.  
I notice some one asking about descriptions of different maneuver,s so I can do one on snap rolls as well if you like and another on gyroscopic effects.
It is sometimes a bit easier just to go and do it so long as you have enough hieght and dont over do the controls.

Control inputs. ( If the prop goes clockwise looking from the cockpit) You can pull up to 45 / 60deg and just when you have enough energy left to do a half snap.  For the snap just bring the stick back gently in about 1sec (Count one thousand and one) at the same time putting in left rudder.  If you are flying a low powered aircraft lead slightly with the rudder.  The aircraft will rotate and is it gets to facing vertically down just nuetralise the controls and recover as you would from a stall and 45deg down line.
Have a good think about it before you try it.  Get it right in your mind.  If you are not sure get an experienced instructor to go with you or feel free to ask about anything you are uncertain of.

Chris Burns

----- Original Message ----- 
From: Virginia M. Jacobson 
To: Chris Burns 
Sent: Sunday, September 29, 2002 7:52 AM
Subject: Re: [Acro] Fw: Vertical Reversements or Cartwheels

Hi Chris

I'm still a little confused on the vertical reversement. You say you pull up to 45 or 60 degrees than 1/2 snap the airplane to come back down the same line? If you 1/2 snap than you are rotating around the longitudinal axis of the airplane and therefore you would still be going up the same ling wouldn't you? Unless what you are referring to is a 180 degree change in direction by YAWing the airplane. I can not visualize the maneuver if you are snapping the airplane. What are the control inputs?

Virginia Jacobson

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