Hi All nicked this from wikipedia:D regarding the bomb dump:
Yardley Chase contains some large concrete huts, about 12m (40 feet) long, and about 6-8m (20-25 feet) wide, which were used during World War II to store bombs. They continued in use after the war, until the 1990s when the Ministry of Defence shut them down when it became obvious that they would be useless in a nuclear war. The site was served by a branch of the Northampton-Bedford railway line and evidence of revetted tracks are still visible around the site which is only a few kilometers East of the former depot of the Royal Pioneer Corps at Simpson Barracks in Wootton.
The Eastern munitions site is larger than its Western neighbour and the bomb storage buildings, in addition to being less numerous, are also mostly surrounded by water-filled moats. The storage buildings at the Western site are surrounded by earth banks. The Eastern site was connected to the Western site by a rail track.
The site is still used by Army cadets and Territorial Army units for basic skills training.
regarding an airfield at Lavendon I can’t find anything!