On October 23, 1999, at 1320 Pacific daylight time, a Cessna 172P, N54844, registered to and operated by Wings of Wenatchee, as a 14 CFR Part 91 instructional flight, and a RV-6A, N811KM, registered to and operated by the pilot as a 14 CFR Part 91 personal flight, collided in mid-air about six miles east of Pangborn Memorial airport, Wenatchee, Washington. Visual meteorological conditions prevailed at the time. No flight plan was filed by the Cessna. The pilot of the RV-6A had filed a VFR flight plan, but had not yet opened it prior to the collision. Both aircraft received minor damage. Neither the flight instructor or private pilot in the Cessna nor the private pilot in the RV-6A were injured. The Cessna had departed from Wenatchee about one hour prior to the collision for the local instructional flight. The RV-6A had just taken off from Wenatchee, and was en route to Joseph, Oregon. The flight instructor in the Cessna reported that the private pilot was working on his instrument rating and was under the hood practicing the VOR-A approach to Wenatchee. The aircraft was flying an inbound course of 285 degrees. At about 3,800 feet, just prior to Malaga final approach fix, and about six miles from the airport, the flight instructor was just about to announce their location and intentions on the Pangborn CTAF frequency (123.0) when they felt a bump. The flight instructor stated that he never saw or heard the other aircraft. The pilot of the RV-6A reported that he had announced his departure from runway 30 on CTAF frequency 123.0. After takeoff, the pilot made a right turn and headed easterly, climbing to 9,500 feet. The pilot stated that at about 4,000 to 5,000 feet, and about six miles from the airport, he suddenly saw the Cessna directly ahead and in his flight path. The pilot immediately pushed the nose down hard in a rapid descending right turn. The left wing tip of the RV-6A came up and collided with the bottom side of the Cessna's right wing tip. Both aircraft received minor damage to their wing tips, and were able to land at Wenatchee without further incident.