Originally Posted by
enviroian
I plan to take the fast train from St Pancras to Ashford International on Monday. My plane gets in at 9 then HEX to Paddington then taxi to St Pancras so I'm guestimating a 1100 train.
Have you done this journey before? The tube from LHR to St Pancras is possibly quicker and more reliable than the HEX and a taxi. The tube from Paddington to St Pancras is probably more reliable as well.
If your flight is scheduled to land at 9, you may not actually get off the plane until 9:20, add 20-60mins to get through non-UK/EU immigrations, meaning you may not even get the 10:12 HEX from T1/2/3, if you do you may not get in a taxi until 10:40, from there the journey can take anywhere from 15-30+ minutes depending on traffic, then get to the right platform/train.
All going well it is possible, but I wouldn't rely on it.