Originally Posted by
Oxon Flyer
30 minutes is, quite literally, only possible on a perfect day with the wind behind.
Just picking a MAN-LHR service at random, say BA1387, and working backwards from today, the in-air times have been 40, 43, 41, 35, 29, 36, 34, 43, 37, 37, 32, 40, 36, 38, 38, 36, 35, 32, 35, 38, 38, 42, 48, 38, 42, 40 mins.
This clearly shows that the planning allowance should be at least 38 - 40 minutes. Once you add on pushback, taxi at each end and a short line-up hold, then 1h10m seems an entirely sensible assumption for the normal gate-to-gate time. Certainly not a significant exaggeration.