Puzzling times...
Strange visitors, odd types, new airlines, yes I can understand the curiosity, but an ageing L1011, whose visits to LHR are not uncommon, still finds space for questions (no one mentioned the Hello Airlines A320 the other day.. )
Operational reasons, yes it was. Passenger flight, yes it was, VIP flight, probably it was, scheduled, no, just an adhoc visit. Need to know, no..
You MUST be a troll if you don't think a TriStar at a commercial airport is worth a mention. In seven years down here I have not seen a single L1011 at Heathrow. Do 216SQ even do VIP stuff these days?