Flight Instructor reported their student found damage to the aircraft propeller while preflighting. Another student who had flown the aircraft prior reported they were informed of the damage.
Synopsis
Flight Instructor reported their student found damage to the aircraft propeller while preflighting. Another student who had flown the aircraft prior reported they were informed of the damage.
Narrative
I completed a preflight inspection of the aircraft; The aircraft showed no signs of anything being damaged or inop. The instructor and I started the aircraft as normal and after ensuring everything was ready headed to the run up area. Run Up was completed as a normal and there we no issues felt or notice; when we attempted to taxi to hold short of the taxi way the aircraft's left brake was stuck; after various attempts to get try and get it unstuck; we shut off the aircraft and got maintenance to come out and check it. The Maintenance employee got it unstuck by putting down the parking break and holding brake pressure while bringing the lever; at this point we still had not noticed any issues. We got back on the aircraft; started it up and did another Run Up Check and everything still operated smoothly. We took and went out [to] ZZZZZ to do a couple of a maneuvers and then headed into ZZZ1 to do short field landings. After completing 3 Landings at ZZZ1 we proceeded to head back to ZZZ; Aircraft was still in smooth operation and during none of the landings was there anything out of the ordinary. Landing into ZZZ everything was normal still; and we proceeded to the ramp and parked the aircraft. Since the instructor had the aircraft for a lesson right after we secured and went inside so that the next student could come out and preflight it. At this point student Person A noticed that all three edges of the prop blades were scratched. I was called back and talk to the Chief Pilot and informed of the next steps to follow.
Second reporter narrative
After doing a run-up in Aircraft X with the parking brake set; we tried to taxi; but the parking brake got stuck; causing us not to be able to taxi; so we troubleshooted to try to get the parking brake unstuck; adding power to try and get the plane to move; and cycling the parking brake. After we couldn't get the parking brake unstuck; we shut down the plane; and I got maintenance to come take a look; and he was able to get the parking brake unstuck. So; we were cleared to go; and nothing abnormal occurred on takeoff or during the entirety of the flight. We did a few commercial maneuvers; including chandelles; slow flight; eights on pylons; and then we did 3 landings; touch and go at ZZZ1; with nothing abnormal on the performance of the aircraft or engine. We headed back to ZZZ and landed normally. After completing the flight and shutting the aircraft down; I went inside to give my next student the keys for the same plane to start preflight. After going back outside to inspect my student pointed out the propeller was damaged in the tips; so I went and got the same maintenance guy who got the parking brake unstuck; and then I squawked the plane in our online software and log book.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.