Apollo 17 Launch Time Change and Azimuth Update Steps

Wedge313

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It looks like the Apollo 17 scenario is set up for the originally scheduled launch time of 02:53. How do I go about changing the launch time to match up with the actual launch time (05:33) after the delay? I think I see how to get the updated launch azimuth (RTCC UTI>IU>LAU) then V78E to input the new azimuth. But I'm not clear on how I get the new lift off time.

Thanks
 

indy91

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The only way to do it right now is to edit the T-4h scenario. Find the line:

MISSNTIME -14400

That is minus 4 hours of mission time. There was a delay of exactly 2:40h, so you need to change that to.

MISSNTIME -24000

if my math is correct there. Sadly we can't do "in-sim" countdown holds and launch updates. It's a little bit annoying for the Apollo mission and a bit more annoying thinking to the future for Skylab missions which needed to launch at a specific time for rendezvous with the Skylab. The reason is that lot of things in the Saturn class use that mission time variable and you can't simply stop the time or set it to something else, things will break very badly. That is something we need to work on for a long time until we got rid of every use of that mission time, then it should be possible to be more flexible with the launch time. On the other hand, it makes it easy to change the launch time outside of the simulation. All you need to change is that one number.

And then as you said, you can use the RTCC MFD to get a new launch azimuth and enter it with V78. After liftoff (before calculating stuff like the TLI PAD) you should then go the config page of the RTCC MFD and update the liftoff time in the RTCC (UPD button), so that is knows when you actually launched. And then much later you will have to do the CMC liftoff time update to get back to the flight plan.
 
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