pub fn ogive_pressure_drag_factor(kappa: f64) -> Result<f64, AeroError>Expand description
Eq. B.8’s ratio of an ogive’s pressure drag to that of the cone with the same length and base
diameter, at transonic and supersonic speeds: 0.72 (κ − ½)² + 0.82 (Niskanen 2009 p. 110),
with κ = ρ_t/ρ the tangent ogive’s arc radius over the ogive’s (0 for a cone, 1 for a tangent
ogive). It is 1 at both ends and 0.82 at κ = ½, after NAVWEPS Report 1488 p. 239: the best
ogive drags “consistently 18% less” than the cone at Mach 1.6 to 2.5 and fineness 2 to 3.5.
§Errors
AeroError::Domain for κ outside [0, 1]: a bulged secant ogive (κ > 1, arc radius
below the tangent ogive’s) is outside the fit.