Simviation Forums

Hi there,

It just came to my mind, that I use it as it has to be used on all the aircrafts I'm flying, I know it has an easily recognizable sound, it has something to do to the air conditioning, and APU performance, but I just realized that I don't know what is it exactly....

What is it exactly?

Greetings, neu

Which packs are you talking about?

The one on commercial jets. All switch on the overhead panel, and it has something to do to air conditioning. Also it has to be turned off at engine start to save power for the APU. This is the only Pack I know, so I cannot answer your question better

Greetings, neu

Pressurisation and Air Cooling Systems - or atleast something like that. Basically, they take compressed air from the engine, cool it, and feed it into the cabin. Keep them on unless you like everyone passing out - Or want extra engine thrust.

http://en.wikipedia.org/wiki/Helios_Airways_Flight_522

Renember.

Packs on - less pnuematic air pressure.
Packs off - more pnuematic air pressure.

So have them OFF for engine start. And off for high performance departures. Typically packs are ON from engine start to aid in passenger comfort.... climbing at 4000ft a min cant be good on the ears.

For the md80 - left engine supplies air the cockpit, right engine supplies air to the cabin. Anti-Ice pneumatic pressure comes from the left or right engines when the pneu X-feed levers are opened or when APU is running. APU is typically in the middle so you will need both Pneu xfeed levers opened if you want air conditioning to cabin or cockpit.

I do not know other aircraft.... but I suspect it will be similar.

This is what I assumed, thanks for confirming it!  [smiley=thumbup.gif]

Greetings, neu

The Packs are the heat exchangers that cool and dry the air coming from the engine prior to use for cabin conditioning (this term also covers pressurisation).
If you hear the term Packs that is what is being talked about. If you hear the term Heat Packs then this refers to the brakes units.
 
Matt