Narrative:

Two cessna 172 aircraft were involved in this incident. Aircraft X was departing ZZZ; and aircraft Y was approaching ZZZ1 [a nearby airport]. Pilot aircraft X departed non-towered airport and continued listening on CTAF until abreast of numbers at northern end of runway; then switched to [approach control frequency] with intention to make contact for VFR advisory. Noted heavy traffic volume on frequency.at approximately 3 miles northeast of ZZZ and altitude approximately 3;000 feet MSL; and while still waiting for clear channel on [approach frequency]; aircraft x experienced impact from above on the left wing. Pilot immediately noticed aircraft Y beside and slightly ahead on the left-hand side; heading in approximately the same direction. Strength of impact felt more comparable to having had a tennis ball thrown at the plane; rather than anything more substantial such as metal-to-metal contact. Pilot of aircraft X immediately reduced engine speed to three-quarter throttle and commenced level flight to assess situation. Concluded that aircraft X was in normal flying condition with no damage apparent; and that aircraft Y had come from 4 o'clock behind and above; and that some part of aircraft Y had impinged on upper surface of left wing of aircraft X. Aircraft Y flew to a lower level and meandered off in the direction of ZZZ1. Pattern of flying of aircraft Y suggested it was observing aircraft X to assess effect of impact. Aircraft X maintained listening on [approach frequency] and heard no transmissions from or to aircraft Y. No communication occurred between the two aircraft. Having concluded that aircraft X was in normal flying condition with no apparent damage; pilot continued with flight to home-base airport after establishing contact with approach and request for VFR advisory. Aircraft X made safe landing at [home-base airport]. Visual inspection of aircraft X showed a small dent; approximately 1/4 inch deep; on the topside of the left wing; more or less just above the attachment point for the wing strut. Light scrape marks coming from the 4 o'clock direction were also visible. From the light scrape marks on the upper wing surface of aircraft X; aircraft Y approached from exactly the 4 o'clock direction. Assuming an airspeed 100 - 115 knots; the relative velocity at impact was 20 - 30 knots. Prior to impact; aircraft Y was not visible since it came from behind and above. As viewed from the cockpit of aircraft Y; aircraft X would have approached from the ten o'clock direction at 15 to 25 degrees below the horizon.

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Original NASA ASRS Text

Title: The pilot of a small aircraft reported contact with another small aircraft from behind and above. Both aircraft were able to continue for normal landing.

Narrative: Two Cessna 172 aircraft were involved in this incident. Aircraft X was departing ZZZ; and aircraft Y was approaching ZZZ1 [a nearby airport]. Pilot aircraft X departed non-towered airport and continued listening on CTAF until abreast of numbers at northern end of runway; then switched to [approach control frequency] with intention to make contact for VFR Advisory. Noted heavy traffic volume on frequency.At approximately 3 miles NE of ZZZ and altitude approximately 3;000 feet MSL; and while still waiting for clear channel on [approach frequency]; aircraft x experienced impact from above on the left wing. Pilot immediately noticed aircraft Y beside and slightly ahead on the left-hand side; heading in approximately the same direction. Strength of impact felt more comparable to having had a tennis ball thrown at the plane; rather than anything more substantial such as metal-to-metal contact. Pilot of aircraft X immediately reduced engine speed to three-quarter throttle and commenced level flight to assess situation. Concluded that aircraft X was in normal flying condition with no damage apparent; and that aircraft Y had come from 4 o'clock behind and above; and that some part of aircraft Y had impinged on upper surface of left wing of aircraft X. Aircraft Y flew to a lower level and meandered off in the direction of ZZZ1. Pattern of flying of aircraft Y suggested it was observing aircraft X to assess effect of impact. Aircraft X maintained listening on [Approach frequency] and heard no transmissions from or to aircraft Y. No communication occurred between the two aircraft. Having concluded that aircraft X was in normal flying condition with no apparent damage; pilot continued with flight to home-base airport after establishing contact with Approach and request for VFR Advisory. Aircraft X made safe landing at [home-base airport]. Visual inspection of aircraft X showed a small dent; approximately 1/4 inch deep; on the topside of the left wing; more or less just above the attachment point for the wing strut. Light scrape marks coming from the 4 o'clock direction were also visible. From the light scrape marks on the upper wing surface of aircraft X; aircraft Y approached from exactly the 4 o'clock direction. Assuming an airspeed 100 - 115 knots; the relative velocity at impact was 20 - 30 knots. Prior to impact; aircraft Y was not visible since it came from behind and above. As viewed from the cockpit of aircraft Y; aircraft X would have approached from the ten o'clock direction at 15 to 25 degrees below the horizon.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.