KevMusic,
Don't worry about the distance, just hit the A1 and go for it! I`ve regularly done Gatwick aerodrome (Hehe) to Lincolnshire (and Yorkshire!) dromes, including Hemswell, and back in day. Just take a mate along to share the driving. If on your own, start early, stop regularly, keep hydrated, and do it when the lighter evenings are here.
Do not drive if tired!!! And all in a Vauxhall Rascal van with 50 odd hp, and bleedin noisy!
GO ENJOY! If you want a little more of a relaxed jolly, take a few days off, stay in a B&B or Youth Hostel (although Lincoln YH closed a while back).
www.yha.org.uk
The links you have also been given will no doubt point to the Kesteven Aerodrome Trails
www.n-kesteven.gov.uk/section.asp?docId=541
If you get the aerodrome bug, try Oxfordshire too for Bomber Command O.T.U stations...and I say no more...:-)
GO ENJOY and show us your pics!