On an unknown date, time, and location, a Piper PA-28R-200, N2882R, operated by Regional Airline Academy Flight Schools, was substantially damaged during an unknown flight operation. The weather is unknown at the time of the accident, and it is unknown if a flight plan was filed. The pilot, and if passengers were on board during the accident, is unknown. It is presumed that there were no injuries. The Federal Aviation Administration (FAA) became aware of structural damage to the airplane during a ramp inspection on July 7, 2005, and notified the National Transportation Safety Board at that time. The left wing's false spar separated just aft of the left main landing gear. Additionally, the left wing support ribs were cracked and there were displaced rivets on top surface skin. The airplane's last annual inspection was performed on February 09, 2005, about 22 flight hours prior to the damage being discovered. Numerous pilots flew the airplane during that duration, none of which reported an event that would result in damage to the airplane. During a telephone conversation with a Safety Board investigator, the operator stated that he does not know when, where, or who damaged the aircraft. The last flight in the airplane was conducted by a certified flight instructor (CFI) and pilot undergoing commercial instruction on March 11, 2005, about 1300 mountain standard time. According to the CFI of the last flight, the student conducted a preflight inspection of the airplane prior to the commercial pilot training flight at Williams Gateway Airport, Phoenix, Arizona. Following takeoff on runway 30L, the student raised the landing gear lever and turned east onto a right crosswind. After retraction, the landing gear transition light remained illuminated. The CFI decided to stay in the traffic pattern and return to the airport for a full stop landing. He manipulated the landing gear lever to the down position and all three landing gear cockpit lights illuminated green, in indication they were extended. The CFI made a precautionary landing without mishap. After the flight he reported the discrepancy with the landing gear transition light and deferred the problem to the maintenance facility. The CFI further stated that he had experienced a similar transition light problem in the accident airplane on two previous flights. He added that several days after his last flight, a mechanic working for Regional Airline Academy Flight Schools showed him damage that the airplane sustained. He observed popped rivets on the upper wing surfaces and other wing surface deformation. The date, time, and location utilized for this accident is referenced from the last flight for computer entry purposes only. A determination was not made regarding the identity of the pilot(s) that caused the damage to the training airplane.