Will be in London 1 night and plan to stay at the Hilton in T4 (flying from Mumbai to London via BA). Will be leaving for NY on AA, which is in T3.
How do I get from T4 to T3? How long will it take?
thanks

Use the Heathrow Express as it's free between terminals.

And it's about 5 minutes

10 mins to walk from terminal 3 arrivals to Heathrow Express unified terminal 1,2,3 station, five minutes on express to terminal 4 (leave every 15 mins) then 15 minutes via walkway linking terminal 4 to Hilton. Heathrow Express is free for intra-airport transfers.

You walk (not a short walk) from the Hilton to the T4 stop of the Heathrow Express (signposted.) You ride the train (free) to the Heathrow Central stop, and from there walk (10 min. according to the HEX, but YMMV) to T3. I would allow a good hour but it may go quicker, or slower if you have to manage heavy bags on and off the HEX.

is heathrow express a bus or train? BA info is not the same.

Heathrow Express is an underground train linking the two terminals (1,2,3 unified stop and 4) and it also goes into Paddington Station in London.
It's expensive to Paddington but free for airport transfers.

Ensure you take the HEX which is free rather than the Tube which isn't.

Also what "BA info"?

BA web site ,changing terminals

http://www.britishairways.com/travel...r/public/en_us

The information there is for connecting flights where you stay airside (ie don't enter the UK) for a few hours before getting another flight.

so alan what is the best way to connect international flights from t3 to t1 with 2hrs and a disable person who will not use a wheelchair ?

<i>so alan what is the best way to connect international flights from t3 to t1 with 2hrs and a disable person who will not use a wheelchair ?</i>

This question of yours was answered on the other thread - just click on your name to see your previous posts.

Look for a green telephone stand/kiosk - with that phone you can call a bus that will take you from terminal to terminal - okay for wheelchairs, or other disabilities, pregnant people, people with too much luggage to manage the ordinary transfers, things like that.