By about 8 years old I had flown on a Comet 4, several 707s and DC8s, then my older brother and I (unaccompanied) had our first flight on a VC10 in the last row of seats and able to see 2 of the engines outside our window. I remember us being knocked out by the acceleration and steep climb and an impressive roar from the engines, but once cruising the engine noise was well masked by wind noise and we reckoned it was noticeably quieter than previous flights. We both still love the VC10.