Which year did the Angeles City based airline begin operations?
CREATE TABLE table_15637071_1 (commenced_operations VARCHAR, headquarters VARCHAR)
SELECT commenced_operations FROM table_15637071_1 WHERE headquarters = "Angeles City"
<s>[INST] Write mssql query to answer the following question given the database schema. Schema: CREATE TABLE table_15637071_1 (commenced_operations VARCHAR, headquarters VARCHAR) Question: Which year did the Angeles City based airline begin operations? [/INST] SELECT commenced_operations FROM table_15637071_1 WHERE headquarters = "Angeles City" </s>