The National Transportation Safety Board (NTSB) is an independent Federal agency with the mission of investigating every civil aviation accident in the country and significant accidents in other modes of transportation, to include railroad, highway, marine and pipeline.  Many safety features currently incorporated into vehicles originated with NTSB recommendations aimed at preventing future accidents. The Safety Board is responsible for determining the probable cause of:
    - all U.S. civil aviation accidents and certain public-use aircraft accidents;
    - selected highway accidents;
    - railroad accidents involving passenger trains or fatalities or major
               property damge;
    - major marine accidents and any marine accident involving a public
               and non-public vehicle;
    - pipeline accidents involving a fatality or major property damage;
    - releases of hazardous materials in all transporation forms; and
    - selected transportation accidents, involving recurring problems.

The NTSB is one of the world's foremost accident investigation agencies, having conducted more than 124,000 aviation accidents and over 10,000 surface transportation accidents since 1967.  The NTSB maintains the government's database of civil aviation accidents and conducts special studies of transportation safety issues with national significance.