Great video rottndog, many thanks. Re: the hold-down clamps at 1:35. Norman Mailer of all people writes of this in his Of A Fire On The Moon, and in prose approaching the sublime:
But for the moment the spaceship does not move. Four giant hold-down arms large as flying buttresses hold to a ring at the base of Saturn v while the thrust of the motors builds up in the nine seconds, reaches a power in thrust equal to the weight of the rocket. Does the rocket weigh six million, four hundred and eighty-four thousand pounds? Now the thrust goes up, the flames pour out, now the thrust is four million, five million, six million pounds, an extra million pounds of thrust each instant as those thousands of gallons of fuel rush every second to the motors, now it balances at six million, four hundred thousand and eighty- four thousand, two hundred and eighty pounds. The bulk of Apollo-Saturn is in balance on the pad. Come, you could now levitate it with a finger, but for the hold-down arms. Now in the next second and the next, the thrust is up to full launch, to seven and a half million pounds, more, more than one million pounds of surplus force is now ready to push upward. And still the rocket is restrained. The hold-down arms, large as butresses will retain the ship for two more seconds before lift-off. The last check-outs race through the automatic sequence and GO comes back, and the hold-down arms - what engineering in those giants! - pull back, and Apollo-Saturn rises inch by inch in those first seconds, pulling tapered pins through dies to slow the instant of the release. Inch by inch, then foot by foot, slowly, story by story, swing-arm by swing-arm, the swing-arms pulling back in the last five seconds, the last two seconds, umbilicals snapping back, slowly Apollo-Saturn climbs up the length of the Mobile Launcher, the flame of apocalypse no more than the sparks of its chariot, and spectators cry, “Go, baby, go.”
Incidentally, those turbines feeding each F-1 are rated at fifty-five thousand horsepower and are as large as a refrigerator. Each could empty a swimming pool of 30,000 gallons of water in less than nine seconds. I just marvel at that rocket and the engineers who designed it.