What was the correct procedure to stop the descent engine on the Apollo 11 LEM?
When the LEM had a contact light on Apollo 11, there was some terminology spoken that I'm assuming is important (and which I find quite interesting regardless).
However, what of this was actually required to stop the engine? As an aside, I think it is highly relevant to ask for a clarification for the following terminology without making a separate question for each phrase. In particular the meaning of:
"ENGINE STOP": Does this actually stop the engine, or is it simply a part of the steps that must be taken? If not, then what is the meaning of the other phrases spoken?
"ACA -- out of detent": What is this? A mechanical fuel pump that is stopped? What is ACA? Attitude Control Assembly (https://www.hq.nasa.gov/alsj/apollo.glossary.html)?
"MODE CONTROL—both AUTO": I don't know what this is.
"DESCENT ENGINE COMMAND OVERRIDE—OFF": I'm assuming this is to prevent the abort stage from firing automatically.
"ENGINE ARM—OFF": Perhaps this is the actual step of stopping the engine, and the "ENGINE STOP" is merely announcing that they now start the procedure of stopping the engine, and this is the final step?
As the LEM descent engine uses hypergolic fuel with a pintle injector, it doesn't seem like a mechanical pump is required.