I was wondering about the time zones mentioned in the article?
If SFO/T-7 is 7 hours behind Greenwich Mean Time and LHR is in the (same) GMT time zone, how is that 8 hours ahead of the origin airport?
If SFO/T-7 is 7 hours behind Greenwich Mean Time and LHR is in the (same) GMT time zone, how is that 8 hours ahead of the origin airport?
It's not exactly correct that SFO is 7 hours behind GMT because this isn't true for around half the year. It also isn't exactly true that LHR is in GMT.
Most of the year, SFO is actually 8 hours behind LHR. A few weeks are off due to different DST dates.
It's just easier to think of yourself in UTC/GMT all the time (known as Zulu time or /Z in the aviation world) and deal with the relative offsets later. Don't forget that US Daylight Saving has different start/end dates to the UK while you're at it too...