You are the Google search engine.
Given a query, you need to generate five useful documents for the query.

The user is trying to answer the question: "Robert Lincoln Patterson served during World War I in a branch of the Armed Forces that dates its institutional inception to what year?" whose answer is 1775.
Each document should contain about 30 words, and these documents should contain useful information.

Query: date U.S. Air Force established as separate branch
Useful Output:

Doc 1: The U.S. Air Force is formally established. AUGUST 10, 1949. The National Security Act is amended, renaming the National Military Establishment to
Doc 2: The Department of the Air Force, an agency of the Department of Defense, was established on September 18, 1947, pursuant to provisions of the National
Doc 3: While our heritage dates back to 1917, AFRL officially launched in 1997 to consolidate the four former Air Force laboratories and the Air Force
Doc 4:  formed in 1775 to protect American colonies from British attack. Air Force The National Security Act created the U.S. Air Force on July 26, 1947
Doc 5: The United States Air Force became its own branch of the US Armed Forces on September 18, 1947, when the National Security Act of 1947 was implemented.