text: Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
  ### Context:
  CREATE TABLE table_15637071_1 (commenced_operations VARCHAR, headquarters VARCHAR)
  ### Question:
  Which year did the Angeles City based airline begin operations?
  ### Answer:
  SELECT commenced_operations FROM table_15637071_1 WHERE headquarters = "Angeles City"