Table: iraqi_air_force_1990
Columns: aircraft
1990
destroyed
damaged
to_iran
survived

Question: What's the to Iran with fewer than 9 survivors, more than 3 damaged, and an ussr an-26 aircraft?
SQL: SELECT AVG("to_iran") FROM iraqi_air_force_1990 WHERE "survived" < 9 AND "aircraft" = 'ussr an-26' AND "damaged" > 3

Question: What's the average destroyed with a 1990 over 12, more than 1 damaged, 6 survivors, and a to Iran less than 4?
SQL: SELECT AVG("destroyed") FROM iraqi_air_force_1990 WHERE "1990" > 12 AND "damaged" > 1 AND "to_iran" < 4 AND "survived" = 6

Question: What's the average survived with a to Iran less than 1, more than 1 destroyed, and a brazil tucano aircraft?
SQL: SELECT AVG("survived") FROM iraqi_air_force_1990 WHERE "to_iran" < 1 AND "aircraft" = 'brazil tucano' AND "destroyed" > 1