The article makes it sound like the ferry mission wasn't quite as tight as you suggested ("barely made it"): "As a precaution, the main A40 trunk road, which r

The article makes it sound like the ferry mission wasn't quite as tight as you suggested ("barely made it"): "As a precaution, the main A40 trunk road, which runs past the bottom of the easterly end of the runway at Northolt, was closed to traffic until the Boeing 707 had taken off. However, much lighter without much of its interior, the aircraft was airborne quickly off the Northolt runway and successfully landed at Heathrow a few minutes later."