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: "when did the air force start wearing abu's?" whose answer is 2 October 2007.
Each document should contain about 30 words, and these documents should contain useful information.

Query: when did the U.S. Air Force start wearing ABUs
Useful Output:

Doc 1: No longer authorized for official wear, many Airmen don't know what to do with their old ABU's. Some have discarded them or relegated them
Doc 2: If anyone needs something to do with all those old ABU's, consider donating to your local Civil Air Patrol cadet squadron. I am a volunteer with
Doc 3: The Air Force had only been wearing ABUs for 6 months when I got to BMT in 2008.  Air Force would switch to OCPs and the ABU was to be retired.
Doc 4: The Air Force has decided to switch from the standard Airman Battle Uniform (ABU) to operational camouflage pattern uniforms for a number of reasons.
Doc 5: The Airman Battle Uniform (ABU) was the official work uniform of the United States Air Force (USAF) from 2007 to 2019. This digital-tiger-stripe