From:
http://en.wikipedia.o...heffield#Airport_name
It was named 'Robin Hood' based on the following local information:
1) The original Robin Hood legends are set in Barnsdale Forest, the area of South Yorkshire which surrounded Doncaster and Pontefract. This legend is reinforced by the fact that the now closed village pub in nearby Hatfield Woodhouse is known as the Robin Hood and Little John.
2) The airport has a historical connection to Nottinghamshire (as the parish of Finningley was, until 1974 and the Local Government Act 1972, administered as part of Nottinghamshire) and still resides in the boundary of the Diocese of Nottingham.
3) The runway extension (completed in 1957) to accommodate Vulcan bombers, extended the airfield into the county of Nottinghamshire.
4) Some later Robin Hood legends - and the popular 20th century books, films and TV programmes are set in Sherwood Forest.
5) The Metropolitan Borough of Doncaster is closer to what is left of Sherwood Forest than the city of Nottingham is.
6) The forests of Sherwood and Barnsdale merged in this area of Yorkshire.
7) The name would provide an identity which would raise a lot of attention (if a little controversy) for the airport and create a marketing opportunity.