Charlotte Douglas International Airport an aviation library with over 9,000 volumes and a very extensive photography collection. Rare aircraft in the collection include one of only two surviving Douglas D-558 Skystreak aircraft and the second (and oldest surviving) U.S.-built Harrier, which was used as the flight-test aircraft and accumulated over 5,000 flight-test hours. In January 2011, the museum acquired N106US, the US Airways Airbus A320 ditched by captain Chesley Sullenberger as US Airways Flight 1549 in the Hudson River on January 15, 2009. This aircraft, which was delivered on June 10, 2011, is about 35 years younger than any other commercial airliner on display
Flock (birds) it is specifically the two different behaviours of the species that compose a mixed flock. Within a mixed flock there can be two different behavioural characteristics: sally and gleaner. Sallies are individuals that act as guards of the flock and consume prey in the air during flight. On the other hand, gleaners are those that consume prey living within vegetation. Studies have shown that as resources in the aerial environment increase, the flock will possess more sallies than gleaners. This has been shown to occur during forest fires in which insects have been flushed from vegetation, however this can also