The museum also offers school tours and a guest speaker program. The museum's library contains an extensive collection of rare items such as aircraft manufacturer company newsletters/magazines, technical manuals for both military and civilian aircraft, industry magazines dating back to World War II and before, historic photographs and other invaluable references on aircraft operation and manufacturing. The museum has on display "The Spirit of Seventy-Six," which is a DC-3 (DC-3-262, Serial No. 3269). After being in commercial airline service, the plane served as a corporate aircraft for Union Oil Company for 32 years. The plane was built in the Douglas Aircraft Company plant in Santa Monica in January 1941, which was a major producer of both commercial and military aircraft. The museum claims to be "the only aviation museum and research center situated at a major airport and the only facility with a primary emphasis on contributions of civil aviation to the history and development of Southern California". There are other museums at major airports, however, including the Udvar-Hazy Center of the National Air and Space Museum adjacent to Washington Dulles Airport, the Royal Thai Air Force Museum at Don Mueang Airport, the Suomen ilmailumuseo (Finnish Aviation Museum) at Helsinki-Vantaa Airport, the Frontiers of Flight Museum at Dallas Love Field, the Tulsa Air and Space Museum & Planetarium at Tulsa International Airport and others. The airport has the administrative offices of Los Angeles World Airports. Continental Airlines once had its corporate headquarters on the airport property. At a 1962 press conference in the office of Mayor of Los Angeles Sam Yorty, Continental Airlines announced that it planned to move its headquarters to Los Angeles in July 1963. In 1963 Continental Airlines headquarters moved to a two-story, $2.3 million building on the grounds of the airport. The July 2009 "Continental Magazine" issue stated that the move "underlined Continental Airlines western and Pacific orientation". On July 1, 1983 the airline's headquarters were relocated to the America Tower in the Neartown area of Houston. In addition to Continental Airlines, Western Airlines and Flying Tiger Line also had their headquarters at LAX. During its history there have been numerous incidents, but only the most notable are summarized below:          The "Imperial Hill" area in El Segundo is a prime location for aircraft spotting, especially for takeoffs. Part of the Imperial Hill area has been set aside as a city park, Clutter's Park. Another popular spotting location sits under the final approach for runways 24 L&R on a lawn next to the Westchester In-N-Out Burger on Sepulveda Boulevard.