Originally Posted by
chevvron
The first Pan Am '747 to arrive at Heathrow did a demo flight for VIPs and local dignitaries in the afternoon just out to Brecon and back.
I was the radar monitor on the frequency on which it contacted London Control after departure (I supplied information to the radar controller by writing flight details on a perspex board with a TV camera behind it which the radar controller then referred to) and remember his immortal first words when he called up:
'London Clipper XXX; we're not gonna make four thousand (feet) by Woodley'.
(Remember it only had about 200 people on board and was not fully fuelled for a transatlantic flight)
Both Pan Am and TWA ran the early 747-100 LHR to Los Angeles. BOAC/British Airways felt it was beyond the range of the aircraft with an economic load until their first Rolls-Royce 747-200Bs arrived, but the US carriers did so.
Bearing in mind that summertime departures were warm early afternoons, when Heathrow would often be on easterlies, and the known reliability of early JT9Ds, there was evident concern in the tower for these, heading out across West London, until it was seen they were clear. Apparently the FE sat with fingers poised over the fuel dump valves, just in case. Pan Am's more extreme cases were known as the "Hedge Clipper", and once the Underground opened out to Heathrow in this time others were "Departing via the Piccadilly Line".
The well-known Continental (actually still in People Express livery) 747 near-thing departing Gatwick showed that there wasn't a lot of margin.