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Hi Dick
            There is quite a list of maneuvers there so I will do this in a few Emails.
Even in the early days there were books written and some of the descriptions were a little vague and then people made there own interpretations of the maneuvers and pilots become confused, not that that's anything to go by.  There are 3 basic types of Barrel Roll only 1 of which we ever used in comps.  The mechanics of Crossover Spins will also require a bit of explaining.  I will get the easy ones out of the way first and when I have a bit more time in the week I will do the others. 
Dutch Roll.  This is not an aerobatic maneuver but is the secondary effect of Yaw.  It is most noticeable in spirally stable aircraft.  If you put in left rudder the aircraft will roll to the left.  If you put in right rudder it rolls right.
Lazy 8.  Is used as an introduction to aerobatics.  It is technically not an aerobatic maneuver.  Imagine you just do a 180deg steep turn except we will go a little bit further just to get back to our start point.  I am flying along and I pick the start point.  I continue on in a straight line for a few seconds and then do a 45deg bank steep turn and continue on through 180deg until I am pointing back at my start point.  I roll out S&L and fly over my start point.
If I do the same thing except as I cross the start point I start climbing up to a nominal 45deg up line and do the same steep turn and decend back to the start point as before I have done a half a Lazy 8. If I do these alternately left and right I have done a full Lazy 8.  A bit like doing a Half Cuban 8 except at 45deg laterally to the horizon..
Chandelle.  Is the next stage from a Lazy 8 but as you reached the apex you continued climbing, rolling and turning back on to a 180 reversal.  You are doing a nominal 45deg bank and nominal 45deg climb turning through 180deg except you continue climbing and dont have to go back to your start ponit just run paralell to your line in. Remember that after you have established the 45deg bank and continue the climb you now have to slowly roll in the opposite direction.  If you are turning left you are rolling right so that you finish upright and not inverted. Its easy, even I can do it.  This is also technically (in the old definition) a non aerobatic maneuver since your angle of bank does not exceed 60deg.  They could get you on the decaying speed in a climb these days (Zoom Climb) if they wanted to get narky.
Since we have got this far we may as well go one step further and describe the next stage The Immelman Turn.  This is the fore runner to the Half Roll off the top. 
In a Half Roll off the Top we pull vertically and continue the half loop until we are horizontal S&L inverted.  We check and roll to uprigjht.  No line between the roll and the half loop but 2 separate elements. 
The Immelman Turn is the same thing except they blended the roll and the loop from about the 1/4 to 3/8 loop position onwards.   Its like a Chandelle but done in the lateral vertical. 
These maneuvers evolved in this rough order.  They were just the natural progression of developement.
Chris Burns
----- Original Message -----
Sent: Saturday, September 28, 2002 11:20 PM
Subject: [Acro] Re: Fw: Vertical Reversements or Cartwheels

I have enjoyed the discussion regarding vertical reversements, stall turns, wingovers etc.  In an effort to keep it going I suggest we describe the following:  Barrel Roll, Crossover Spin, Lazy Eight,  Dutch Roll,  Chandelle.  (no fair using the FAA  PTS description for Lazy Eight and Chandelle as that is only one country's opinion.)

One of the great services performed by IAC (beginning with Don Taylor) and subsequently CIVA is the agreement on international standards for the perfectly flown maneuver.  The maneuvers I have listed above (cross-over spin was, but is going away) are not described by CIVA/IAC and therefore subject to numerous interpretations.

Dick Rihn

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