L18-C95,
I am not familiar with competition aerobatics, but it seems you are talking about pure rather than practical side slip, forward slip, and skidding turn. It is true that directing our course down the centerline extended through touchdown and roll out is the objective of the rudder and prevention of drift is the objective of aileron in the side slip. It is true that directing our butt down the centerline extended to desired altitude on final is generally the objective of the forward slip where rudder is used to hold the nose off course while aileron is used to direct our butt down the centerline extended. It is true that skidding, using rudder only to push the nose around, is more efficient in rate of turn than a coordinated turn.
While purity of separation of control function (uncoordinated rudder and aileron) is desirable in side slip to get down on one wheel without drift and in the skidding turn to prevent a wing going down into the ground, there are situations where we need flexibility.
When Motoadve made the rudder turn on takeoff, the objective was both to stay in low ground effect for good energy management and to prevent putting a wing into the ground. A pure, or nearly pure, rudder turn was necessary. Terrain consideration was to not waste energy to the point of stall trying to outclimb terrain straight ahead or in a climbing coordinated turn.
When Motoadve was turning/descending base to final in the drainage, he was skidding as necessary to increase the rate of turn. He was also forward slipping as necessary to increase rate of descent. We can increase rate of descent, as necessary, with unbalanced extra bank. We can increase rate of turn, as necessary, with unbalanced extra rudder.
In either air to air maneuvering or in air to ground maneuvering, objective is primary. Purity of coordination is generally desirable. Purity of uncoordinated rudder/aileron is desirable in side slip to maintain longitudinal axis alignment. Purity of uncoordinated rudder/aileron in the rudder turn in low ground effect. Sort of mixed up in the forward slip while turning to landing but changing to skidding turn close to terrain.
Principles still in effect. Tactical situations can be fluid. Not always pretty, just mission orientation.
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