What are packs (not PAX!)
 

When you hear about engine bleed and packs, what are the packs? AC packs?
LJ.

L.J.
You are correct. It is a term used by Boeing (and possibly others) to refer to Engine bleed air, and air-conditioning packs.

419

LJ - have a look around this site

Thanks guys.
LJ.

P-neumatic A-ir C-onditoning K-it.

When I first read your question Lump Jockey,I didn't have my glasses on and thought you were referring to "Bleeding Pax". That's a Cabin Crew term, not a Tech Crew term.

Now that I've got my glasses on and re-read your question, you'd better believe the other respondants. They got it right.