Originally Posted by
Genius1
I don't think you have enough 'comfortable' time to go landside. I would stay airside.
You have to think how long the immigration and customs process takes at T5, then your time in the arrivals lounge, factoring in a maximum 15 minute wait for the HEx at T5 to take you to T1/T3, and then another maximum wait of 15 minutes for the Heathrow Connect to take you to T4, plus the time taken to check in and clear security at T5, and a potentially long walk to the gate in T4.
Well the timetable is:
Depart T5
57 - 12 - 27 - 42
Arrive T1 + 3
03 - 18 - 33 - 48
Depart for T4 (train arrives)
10 - 25 - 40 - 55
Arrive at T4
22 - 37 - 52 - 07
Thus, once you leave T5, it takes 25 minutes to reach Terminal 4. Thus, the
maximum journey time is 40 minutes.