What was found
FIFTEEN MINUTES AFTER TAKE-OFF, EXPERIENCED FAILURE OF RT ENGINE, WHILE CLIMBING, LEAVING, EVERYTHING WAS NORMAL. NO PREVIOUS ENG ABNORMALITY HAD BEEN NOTED. AT APPROX 20,000 FEET, HEARD LOUD BANG AND EXPERIENCED VIBRATIONS FROM RT ENGINE. ENGINE LOST POWER, VERIFIED AFFECTED ENGINE, SHUT IT DOWN. CONTINUED WITH APPROPRIATE CHECKLIST. HAVING TIME AND ALTITUDE, ATTEMPTED A WINDMILLING AIR-START. (SINCE NO FIRE OR APPARENT DAMAGE WAS NOTED). ENGINE RESTARTED AND AFTER A FEW SECONDS, SHUT ITSELF OFF AGAIN. SECURED ENGINE PER CHECKLIST AND RETURNED FOR UNEVENTFUL LANDING. UPON LANDING, MADE VISUAL INSPECTION. FORWARD AND AFT TURBINES WERE UNABLE TO BE MOVED BY HAND. NO VISIBLE DAMAGE OR FLUID LEAKS.