The private pilot was preparing to land his gyroplane when he encountered a downdraft, which increased his rate of descent. The pilot was unable to arrest the descent rate and landed hard. As a result, the left main gear axle broke causing the lower rudder strut to contact the ground. The strut bent upwards into the propeller, splintering the propeller and causing substantial damage to approximately 12 inches of the 68-inch-long rudder. The pilot reported that the downdraft was caused by an 80-degree crosswind that blew over houses just to the northeast of the runway threshold. The pilot did not report any mechanical deficiencies with the gyroplane prior to the accident.