They should have been living there in the 70s and 80s when 1-11s were the norm.
I was, then the 737-200s.
In fact Kinsborune Green had quite a few pilots (ex RAF) as did Hatchin Green. A good few worked at Hatfield for BAe as well at Luton Airport (Court Line Days).
Whenever I go back to Harpenden, it seems full of stangers now!