Author Topic: apollo trans-earth-injection  (Read 2320 times)

dom

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apollo trans-earth-injection
« on: August 08, 2016, 09:28:08 AM »
Hello to all,

I am not very familiar with the real behaviour of the trans-earth-injection of the from the apollo missions. I searched the internet and I didn't find any program noun for this operation. Was the burn manually and was there a earth-orbit-injection program too which breakes the CM for the reentry? If I use the reentry mission the, the Apsis is much too small so there must be a "breaking burn".

Thank you in advance.

jcarrion

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Re: apollo trans-earth-injection
« Reply #1 on: August 08, 2016, 03:31:45 PM »
well , there was no braking program  in the Apollo missions . Essentially every burn > 1000ms (i.e. , hyperbolic orbit /excenrticity > 1.0f )  on the outer (far)  side of the moon will -more or less- bring the CM/SM back to earth .  

then -depending on the success of the burn - they adjusted the orbit such as the perigee just touches the atmosphere ,(lower point of the  orbit -using now the earth as the reference - ) , and hence decelerating the capsule.   you can adjust a lot of the reentry point by just a few m/s adjustment. 

Well make a video abt this shortly .

Thanks

dom

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Re: apollo trans-earth-injection
« Reply #2 on: August 08, 2016, 06:48:10 PM »
Thank you very much for these infos! If it is ok, it would be very nice if you create a video. Thank you in advance!!!

dom

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Re: apollo trans-earth-injection
« Reply #3 on: August 09, 2016, 10:35:36 AM »
Hey jcarrion,

i tried it ant it works fine. I set the PGE to about 6360km and it touches the atmosphere like you said.
The descend was very comfortable ;D . The only strange thing was the big braking acceleration while the chute opens (from about > 1000m/s to 25m/s ?!?). Is this a realistic behaviour?

Thank you very much!