On February 17, 2008, at 1230 Pacific standard time, a Piper PA-22 Tripacer, N3316A, experienced a hard landing and subsequent ground loop at Gillespie Field, El Cajon, California. The private pilot operated the airplane as an instructional flight under the provisions of 14 CFR Part 91. The private pilot under instruction and the flight instructor were not injured, and the airplane was substantially damaged. Visual meteorological conditions prevailed, and no flight plan had been filed. The flight originated at Gillespie Field at 1130. The pilot stated in the Pilot Operator Aircraft Accident Report that he was with a certified flight instructor (CFI) on a tail wheel familiarization flight. While en route to Gillespie Field they experienced a loss of radio communications. He set his transponder to 7600, overflew the field at pattern altitude, and received a green light from the tower. He entered the pattern and started his final approach at 70 knots with one notch of flaps, which was how the airplane was configured for his previous landings. On short final the CFI called for full flaps. As the flaps were moved to the full position airspeed decreased and the rate of descent increased. The pilot added power and lowered the nose in an attempt to maintain the glide slope. At 15 to 20 feet agl the airplane began to settle, and then bounced during landing. The CFI called to close the throttle, and the airplane bounced a second time. The airplane swerved left, the CFI applied right rudder, the airplane then swerved right, and the pilot and CFI applied left rudder and left brake. The plane continued to perform a ground loop to the right and the left wing dug into the terrain, causing substantial damage to the wing structure.