It would be helpful to know the exact itinerary. I think the BA194 is the Houston - LHR flight and based on the "take the train" comment it seems as if the onward connecting flight is domestic UK (although theoretically it could be Brussels, Paris or Amsterdam via Eurostar). If it's international - domestic T5 - T5 then MCT is exactly one hour as I was looking at this specific topic yesterday for my own flights.