Great pics!
Pan Am Connie - was that "Round the World" service "Clipper One"? Remember that in the 70s with 747s! Woul;d have preferred to see the Connies of course!
The DC-4 with Merlins was the Canadair C-4 Argonaut... one of BOAC's survived on the fire dump at EGLL until relatively recently...
DC-4M does also ring a bell though...
Now, these pics have galvanised me - I have two 8 or 16mm cinefilm reels labelled, tantalisingly, "LAP" which I take to mean "London Air Port" and "Airshow". They were shot in the 50s by either my dad or my grand-dad. I MUST get down to the camera shop and see if I can get them transferred on to VHS or CD and see what's on them... There's also quite a lot of stuff shot on Madeira, so the possibility of Aquilla Airways Solents...
Cheers
Treadders