Originally Posted by
Discorde
More snippets from the 1969 LHR AIP:
Pilots wishing to use the maximum possible take-off distance on Runway 28R must notify ATC (Extension 5100) and the London (Heathrow) Airport Constabulary (Extension 7555) 30 minutes before ETD to enable the perimeter road at the end of the clearway to be cleared of traffic.
Runways 28L/R will normally be used in preference to runways 10L/R when the tailwind component is no greater than 5 knots and the runway surface is dry.
When the associated cross-wind component on these main runways exceeds 12 knots, a runway more nearly into wind will normally be used.
When a westerly traffic flow is in operation, there will be a preferential use of 28L for landing and 28R for take-off. Operators should advise ATC in advance when operational considerations prevailing for a particular flight will require 28L for take-off.
Pilots are warned that the relative positions of the gasholders at Southall and South Harrow to Runway 23L at Heathrow and Runway 26 at Northolt, have on occasion caused confusion. The letters "LH" and an arrow pointing to Runway 23L at Heathrow are painted on the gasholder at Southall on its north-east side. The letters on the north-east side of the South Harrow gasholder are "NO" with an arrow pointing to Runway 26 at Northolt. Letters and arrows are in white and 30 feet high.
There is also a description of the Daylight Route Indicator (DRI) to assist pilots taxiing in daytime. Boards were situated adjacent to stop bars and showed correct routing using white lights on a black-and-white diagram of the nearby taxiways. My memory says that this system was withdrawn from service by 1972.
These days they'd need to look out for the Waitrose in South Harrow instead of the gas holder.... Still a source of hot air perhaps?