Abstract This work is part of the DIMPACT project that addresses breaking-wave-induced loads on floating wind turbines. In this context, the hydrodynamic impact of a strong plunging breaking wave on a cylinder is studied using semi-analytical models, with a focus on the loads sensitivity to the cylinder tilt and wave-cylinder relative motion. Two semi-analytical models are applied in a strip theory approach under the Froude-Krylov assumption. A numerical wave is generated using a Fully Nonlinear Potential Flow (FNPF) solver, whose free surface geometry and kinematics feed the semi-analytical models. Semi-analytical slamming loads are compared with force measurements collected in a wave flume for different pitch angles and surge speeds. The temporal variation of the force as well as the maximum force acting on the cylinder are well estimated by the semi-analytical models. A new engineering formula is finally developed, accounting for the inclination and surge motion of the cylinder. The impact loads computed with this formula also show good agreement with the experimental tests.