Originally Posted by
NWIFlyer
You can do the journey using one of the two options I gave in about 15-22 minutes depending on which bus you catch (U3 will be quicker). By contrast, going via T5 then Liz Line/Underground will likely roughly double that.
By contrast, for going the other way - landing at T5 and getting to Bath Road - my instinct if with minimal luggage would be to get Tube/train to T2/3 and then pick up one of the many buses from Heathrow Central from there.