Quote: "Average times now by train or Underground
Heathrow 45 minutes
Gatwick 58 minutes
Luton 1 hour 36 minutes
Southampton 1 hour 45 minutes
Stansted 1 hour 53 minutes
Southend 2 hours 2 minutes"
There's no train/underground between Heathrow and Twickenham, LTNman, it's one or two buses, depending on terminal. If driving, 15-20 minutes.