Ideal twist
The relation in Equation (3.33) contains one particular case when l is indeed constant, namely if qr is constant along the span, that is qt being the pitch angle at the tip. This non-linear twist is not physically realizable near the root but the case is of interest because, as momentum theory shows, uniform induced velocity corresponds to minimum induced power. The analogy with elliptic loading for a fixed-wing aircraft is again recalled. The twist in Equation (3.34) is known as ideal twist. Inserting in Equation (3.21) gives
The relation in Equation (3.33) contains one particular case when l is indeed constant, namely if qr is constant along the span, that is qt being the pitch angle at the tip. This non-linear twist is not physically realizable near the root but the case is of interest because, as momentum theory shows, uniform induced velocity corresponds to minimum induced power. The analogy with elliptic loading for a fixed-wing aircraft is again recalled. The twist in Equation (3.34) is known as ideal twist. Inserting in Equation (3.21) gives
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