Xref: utzoo sci.space:4510 sci.space.shuttle:523
Path: utzoo!linus!husc6!bbn!uwmcsd1!ig!agate!ucbvax!hplabs!hplabsb!dsmith
From: dsmith@hplabsb.UUCP (David Smith)
Newsgroups: sci.space,sci.space.shuttle
Subject: Re:  Saturn V takeoff
Message-ID: <4532@hplabsb.UUCP>
Date: 5 Feb 88 19:32:26 GMT
References: <7049@ihlpa.ATT.COM> <1988Feb4.164741.6228@jarvis.csri.toronto.edu>
Organization: Hewlett-Packard Laboratories
Lines: 21

In article <1988Feb4.164741.6228@jarvis.csri.toronto.edu>, hogg@csri.toronto.edu (John Hogg) writes:
> In article <7049@ihlpa.ATT.COM> animal@ihlpa.ATT.COM (D. Starr) writes:
> >A while ago, somebody asked how long it took a Saturn V to clear the launch
> >tower.  I had an opportunity to time it just the other night when the PBS
> >series "Television" re-ran the original network feed from the Apollo 11
> >launch.  From this program it looks like about six and a half seconds pass
> >between the word "liftoff" and the first stage fins passing the crane at
> >the top of the tower, a distance of about 400 feet...
> 
> According to the book ``Project Apollo'' (published 1971, original edition
> 1969) the time to clear the tower is greater than 20 seconds.  That may
> well be starting from ignition; the context concerned the mechanism by which
> the upper service booms retract into their shields before five F-1 engines
> at full power come past.

My recollection is that control passed from Kennedy to Johnson (hmmm...
must be a message in there somewhere) at T+13 seconds, that being the
time it took to clear the tower.  F-1 ignition was supposed to be at
T-8.9 seconds.

		David Smith