All weather lifeboat launched at 1200 to yacht inward bound passing Sea Reach 7 buoy, who has an injured person onboard after slipping down companionway to cabin. ALB on scene at 1232 and 3 casualty care trained crew transferred. Injured person evacuated to ALB and brought back to Sheerness, where they were landed to awaiting Ambulance. ALB ready for service at 1320. NE 4.