On October 10, 2001, about 1600 eastern daylight time, a Piper PA-34-200T, N91284, was substantially damaged during landing at the Northeast Philadelphia Airport (PNE), Philadelphia, Pennsylvania. The certificated flight instructor and commercial pilot were not injured. Visual meteorological conditions prevailed for the instructional flight that departed Perkiomen Valley Airport (N10), Collegeville, Pennsylvania. No flight plan was filed for the flight conducted under 14 CFR Part 91. According to the flight instructor, the tower advised them to enter a right base for runway 24. The pilot reduced the airspeed, and added one notch of flaps. He then lowered the landing gear, and verbalized it was down with "three in the green" and "one in the mirror." The instructor looked at the landing gear indicator, and confirmed that the gear was down and locked. The instructor called for the "prelanding checklist," and the pilot confirmed it was complete. The tower cleared the airplane to land. On short final, the instructor called out mixture rich, propellers full forward, and landing gear down with "three green." The airplane touched down and everything seemed normal. The instructor even commented to the pilot, "nice landing." While the airplane was rolling-out, the right main landing gear collapsed, and the airplane veered to the right. The instructor stepped on the left rudder in an attempt to maintain directional control. The right wing struck a runway light, and the nose gear collapsed. The airplane came to a stop, and the instructor along with the pilot exited under their own power. According to a Federal Aviation Administration inspector, the airplane came to rest with the left main landing gear down and locked. Examination of the right main landing gear revealed no preimpact failures or malfunctions. According to a witness, the nose wheel, along with the left and right main landing gear were down when the airplane landed.