Constant CONE_TABLE_CAP_RAD 

pub const CONE_TABLE_CAP_RAD: f64 = _; // 0.52359877559829882f64

The steepest cap the method can be given, 30°: the steepest cone its normal-force slopes cover (crate::shock_expansion::cone_normal_force_slope), where NASA SP-3007’s tables stop (“cone angles from 2.5° to 30°”, Foreword, p. iii). A handover steeper than this has no tangent cone to start the march from.