An Embraer EMB-145LR, N825MJ, operated by Mesa Airlines as US Airways Express flight 5733, was substantially damaged while landing at Roanoke-Blacksburg Regional Airport (ROA), Virginia. There were no injuries. The flight originated at Pittsburgh International Airport (PIT), Pennsylvania. No problems were reported with the en route or approach phases, and the flight was radar vectored for a visual approach to runway 33. According to the captain there was an abrupt drop in indicated airspeed while on short final approach to landing at Roanoke. He applied power accordingly and landed without apparent incident. A visual inspection was performed at the gate because the landing was considered more firm than usual. The visual post flight inspection noted nothing unusual, nor any damage to the aircraft. The accident airplane was subsequently flown to Charlotte, North Carolina, where a crew swap took place. The departing flight crew did not report any damage on the airplane, and the damage was finally discovered by the accepting flight crew at Charlotte during a pre-flight inspection. Scraped skin was visible on the lower aft fuselage in an area 10 feet long and 3 feet wide. An internal examination revealed the airplane was safe for an unpressurized ferry flight to a heavy maintenance facility. There, it was determined that the airplane had broken and cracked frames and stringers, popped rivets, and the skin had been worn through in the lower aft pressure vessel. PROBABLE CAUSE: “The captain’s failure to maintain airspeed which resulted in an inadvertent stall/mush, and hard landing. Factors were the failure of both pilots to follow company CRM and flight manual procedures, and the captains improper approach briefing.”