Narrative:

About 200-400 feet after liftoff we heard a noise but felt nothing and determined it was not in the plane but outside. We agreed (3 of us on board which included another pilot and a student pilot) that the sound probably came from the ground and with all the large jet operations here could have been from a plane there as we were still over the airport environment.after landing; we attended a brief meeting down from the FBO and on our return to the plane noticed a blue color inside the left hand engine. Upon closer examination; we determined that the blue was actually the core of the inside of the engine that had been gouged. We saw a lot of FOD; bending fan blades and gouging the inside of the engine.we did not fly the plane again and had it towed to the maintenance shop adjacent to the FBO. We originally thought it may have been a drone that hit us. However; after towing the plane into the hangar I began looking for my keys to the plane. Not finding them; there is a chance that they were inadvertently left in the lock and got sucked into the engine. I am still calling the FBO and the car rental place to see if they have them as we're not sure but it could be the reason.

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Original NASA ASRS Text

Title: EA50 pilot reported a strange noise just after takeoff but no cause was determined. After landing significant FOD was discovered in the left engine. After towing to the hangar; the keys to the aircraft could not be found and the reporter believed they may have been left in the door lock during flight.

Narrative: About 200-400 feet after liftoff we heard a noise but felt nothing and determined it was not in the plane but outside. We agreed (3 of us on board which included another pilot and a student pilot) that the sound probably came from the ground and with all the large jet operations here could have been from a plane there as we were still over the airport environment.After landing; we attended a brief meeting down from the FBO and on our return to the plane noticed a blue color inside the left hand engine. Upon closer examination; we determined that the blue was actually the core of the inside of the engine that had been gouged. We saw a lot of FOD; bending fan blades and gouging the inside of the engine.We did not fly the plane again and had it towed to the maintenance shop adjacent to the FBO. We originally thought it may have been a drone that hit us. However; after towing the plane into the hangar I began looking for my keys to the plane. Not finding them; there is a chance that they were inadvertently left in the lock and got sucked into the engine. I am still calling the FBO and the car rental place to see if they have them as we're not sure but it could be the reason.

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.