13 more things that saved Apollo 13

[ka9q]

It seems like keeping the SM was the conservative decision to make once it was determined the consumable were sufficient to make it back with the dead weight still attached.

I agree. But it was not at all clear for some time that the consumables would be sufficient. So during that time I would have looked very closely at the option of jettisoning the SM to increase the delta-V available from the LM descent engine to speed the trip home.

[Echnaton]

There isn't any one source I can point to, but it is my understanding that the decision to do the free return trajectory burn, with the SM in tow, was made once the consumables question was answered.  The consumables questions was really water as the LM had plenty of O2. A dehydrated crew would survive.   

Ars Technica did a write up on this today.


http://arstechnica.com/science/2015/04/apollo-13-the-mistakes-the-explosion-and-six-hours-of-live-saving-decisions/

At the end they point to the great 2005 IEEE Spectrum article "Apollo 13, We Have a Solution."  For those who have not read it, take an hour or so and indulge yourself. 
http://spectrum.ieee.org/aerospace/space-flight/apollo-13-we-have-a-solution


The IEEE article posits that for the SM drop to have made a significant difference, 36 hours saved vs 12, it would have had the draw backs of exposing the heat shield to space and useing nearly all the fuel in the Aquarius decent stage.  Since water was sufficient for the longer journey, it was the conservative decision to tow it along. 
 

[DD Brock]

Thank you for posting that link, great article!