Blimey, I remember the Dart Herald. My first experience of air travel was on one from LGW to Guernsey back in 1979. I remember Guernsey airport being pretty basic – bags were offloaded from plane onto trolley pulled by a farm tractor. The baggage system was a collection of wooden rollers – not motorised. IIRC Guernsey had a restriction on jets due to a combination of the noise and short runway. Have sneaking feeling that ground power was also absent.