Author Topic: STS-1 Countdown  (Read 1037 times)

Offline trebloc

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STS-1 Countdown
« on: 06/02/2015 07:00 AM »
Looking at the STS-1 launch the main engines seem to ignite at about T-3 seconds or so. Was this the case? If so why did they change it to T-6.8 for all the following launches?
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Offline Jim

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Re: STS-1 Countdown
« Reply #1 on: 06/02/2015 10:48 AM »
Looking at the STS-1 launch the main engines seem to ignite at about T-3 seconds or so. Was this the case? If so why did they change it to T-6.8 for all the following launches?

Because they hadn't incorporated the time for the twang rebound in the countdown.  For STS-1, liftoff wasn't until T+3 seconds.

Offline trebloc

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Re: STS-1 Countdown
« Reply #2 on: 06/02/2015 10:53 AM »
Thanks Jim, I always wondered about that. :)
A celibate clergy is an especially good idea, because it tends to suppress any hereditary propensity toward fanaticism.
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