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CHANGELOG.md

@@ -41,7 +41,8 @@ Also, for at least one version before a breaking change, AeroSandbox development
 
 #### 4.1.4
 
-- Added `asb.LiftingLine`, which is an experimental new 3D aerodynamics analysis method. Basic method is a lifting line theory method (with sweep and dihedral accounting), where the linearized sectional data is taken from NeuralFoil results for improved accuracy. Fuselage modeling is handled through a semi-empirical method (essentially, falling back on `asb.AeroBuildup`). Preliminary testing on full-aircraft configurations indicates good agreement with other solvers, but production use should likely wait until more testing is performed in future versions.
+- Public release of `asb.NonlinearLiftingLine`, which is a new 3D aerodynamics analysis method implemented by Yashil Choony at Politecnico di Milano. It is implicitly solved (i.e., by iteration), subclassing `asb.ImplicitAnalysis`. This is a nonlinear lifting line theory method (with sweep and dihedral accounting), where the CL(alpha) function used to drive the nonlinear closure loop is taken from NeuralFoil. Fuselage influences can be optionally handled using a source-line (i.e. nonlifting) method. Preliminary testing on full-aircraft configurations indicates good agreement with other solvers, but production use should likely wait until more testing is performed in future versions.
+- Added `asb.LiftingLine`, which is an experimental new 3D aerodynamics analysis method. It is explicitly solved by linearizing about the "naive" incidence angle on each surface. Basic method is a lifting line theory method (with sweep and dihedral accounting), where the linearized sectional data is taken from NeuralFoil results for improved accuracy. Fuselage modeling is handled through a semi-empirical method (essentially, falling back on `asb.AeroBuildup`). Preliminary testing on full-aircraft configurations indicates good agreement with other solvers, but production use should likely wait until more testing is performed in future versions. Stability derivatives with respect to alpha and beta appear accurate, but rate derivatives (p, q, r) are not yet tested.
 - Added save/load capabilities for AeroSandboxObjects (parent class of Airplane, Wing, Airfoil, etc.) via `AeroSandboxObject.save()` and `asb.load()`.
 
 #### 4.1.3