Database: pilot_record
Question: Show the fleet series of the aircrafts flied by pilots younger than 34
SQL:
SELECT T2.Fleet_Series FROM pilot_record AS T1 JOIN aircraft AS T2 ON T1.Aircraft_ID  =  T2.Aircraft_ID JOIN pilot AS T3 ON T1.Pilot_ID  =  T3.Pilot_ID WHERE T3.Age  <  34